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apache / hbase / 1726160839368df14602da1618e3538955b25f74 / . / hbase-common / src / main / java / org / apache / hadoop / hbase / util / Bytes.java
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/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.hadoop.hbase.util;
import static org.apache.hbase.thirdparty.com.google.common.base.Preconditions.checkArgument;
import static org.apache.hbase.thirdparty.com.google.common.base.Preconditions.checkNotNull;
import static org.apache.hbase.thirdparty.com.google.common.base.Preconditions.checkPositionIndex;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.math.BigDecimal;
import java.math.BigInteger;
import java.nio.ByteBuffer;
import java.nio.charset.StandardCharsets;
import java.security.SecureRandom;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellComparator;
import org.apache.hadoop.io.RawComparator;
import org.apache.hadoop.io.WritableComparator;
import org.apache.hadoop.io.WritableUtils;
import org.apache.yetus.audience.InterfaceAudience;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import sun.misc.Unsafe;
import org.apache.hbase.thirdparty.org.apache.commons.collections4.CollectionUtils;
/**
* Utility class that handles byte arrays, conversions to/from other types,
* comparisons, hash code generation, manufacturing keys for HashMaps or
* HashSets, and can be used as key in maps or trees.
*/
@SuppressWarnings("restriction")
@InterfaceAudience.Public
@edu.umd.cs.findbugs.annotations.SuppressWarnings(
value="EQ_CHECK_FOR_OPERAND_NOT_COMPATIBLE_WITH_THIS",
justification="It has been like this forever")
public class Bytes implements Comparable<Bytes> {
// Using the charset canonical name for String/byte[] conversions is much
// more efficient due to use of cached encoders/decoders.
private static final String UTF8_CSN = StandardCharsets.UTF_8.name();
//HConstants.EMPTY_BYTE_ARRAY should be updated if this changed
private static final byte [] EMPTY_BYTE_ARRAY = new byte [0];
private static final Logger LOG = LoggerFactory.getLogger(Bytes.class);
/**
* Size of boolean in bytes
*/
public static final int SIZEOF_BOOLEAN = Byte.SIZE / Byte.SIZE;
/**
* Size of byte in bytes
*/
public static final int SIZEOF_BYTE = SIZEOF_BOOLEAN;
/**
* Size of char in bytes
*/
public static final int SIZEOF_CHAR = Character.SIZE / Byte.SIZE;
/**
* Size of double in bytes
*/
public static final int SIZEOF_DOUBLE = Double.SIZE / Byte.SIZE;
/**
* Size of float in bytes
*/
public static final int SIZEOF_FLOAT = Float.SIZE / Byte.SIZE;
/**
* Size of int in bytes
*/
public static final int SIZEOF_INT = Integer.SIZE / Byte.SIZE;
/**
* Size of long in bytes
*/
public static final int SIZEOF_LONG = Long.SIZE / Byte.SIZE;
/**
* Size of short in bytes
*/
public static final int SIZEOF_SHORT = Short.SIZE / Byte.SIZE;
/**
* Mask to apply to a long to reveal the lower int only. Use like this:
* int i = (int)(0xFFFFFFFF00000000L ^ some_long_value);
*/
public static final long MASK_FOR_LOWER_INT_IN_LONG = 0xFFFFFFFF00000000L;
/**
* Estimate of size cost to pay beyond payload in jvm for instance of byte [].
* Estimate based on study of jhat and jprofiler numbers.
*/
// JHat says BU is 56 bytes.
// SizeOf which uses java.lang.instrument says 24 bytes. (3 longs?)
public static final int ESTIMATED_HEAP_TAX = 16;
static final boolean UNSAFE_UNALIGNED = UnsafeAvailChecker.unaligned();
/**
* Returns length of the byte array, returning 0 if the array is null.
* Useful for calculating sizes.
* @param b byte array, which can be null
* @return 0 if b is null, otherwise returns length
*/
final public static int len(byte[] b) {
return b == null ? 0 : b.length;
}
private byte[] bytes;
private int offset;
private int length;
/**
* Create a zero-size sequence.
*/
public Bytes() {
super();
}
/**
* Create a Bytes using the byte array as the initial value.
* @param bytes This array becomes the backing storage for the object.
*/
public Bytes(byte[] bytes) {
this(bytes, 0, bytes.length);
}
/**
* Set the new Bytes to the contents of the passed
* <code>ibw</code>.
* @param ibw the value to set this Bytes to.
*/
public Bytes(final Bytes ibw) {
this(ibw.get(), ibw.getOffset(), ibw.getLength());
}
/**
* Set the value to a given byte range
* @param bytes the new byte range to set to
* @param offset the offset in newData to start at
* @param length the number of bytes in the range
*/
public Bytes(final byte[] bytes, final int offset,
final int length) {
this.bytes = bytes;
this.offset = offset;
this.length = length;
}
/**
* Get the data from the Bytes.
* @return The data is only valid between offset and offset+length.
*/
public byte [] get() {
if (this.bytes == null) {
throw new IllegalStateException("Uninitialiized. Null constructor " +
"called w/o accompaying readFields invocation");
}
return this.bytes;
}
/**
* @param b Use passed bytes as backing array for this instance.
*/
public void set(final byte [] b) {
set(b, 0, b.length);
}
/**
* @param b Use passed bytes as backing array for this instance.
* @param offset
* @param length
*/
public void set(final byte [] b, final int offset, final int length) {
this.bytes = b;
this.offset = offset;
this.length = length;
}
/**
* @return the number of valid bytes in the buffer
*/
public int getLength() {
if (this.bytes == null) {
throw new IllegalStateException("Uninitialiized. Null constructor " +
"called w/o accompaying readFields invocation");
}
return this.length;
}
/**
* @return offset
*/
public int getOffset(){
return this.offset;
}
@Override
public int hashCode() {
return Bytes.hashCode(bytes, offset, length);
}
/**
* Define the sort order of the Bytes.
* @param that The other bytes writable
* @return Positive if left is bigger than right, 0 if they are equal, and
* negative if left is smaller than right.
*/
@Override
public int compareTo(Bytes that) {
return BYTES_RAWCOMPARATOR.compare(
this.bytes, this.offset, this.length,
that.bytes, that.offset, that.length);
}
/**
* Compares the bytes in this object to the specified byte array
* @param that
* @return Positive if left is bigger than right, 0 if they are equal, and
* negative if left is smaller than right.
*/
public int compareTo(final byte [] that) {
return BYTES_RAWCOMPARATOR.compare(
this.bytes, this.offset, this.length,
that, 0, that.length);
}
/**
* @see Object#equals(Object)
*/
@Override
public boolean equals(Object right_obj) {
if (right_obj instanceof byte []) {
return compareTo((byte [])right_obj) == 0;
}
if (right_obj instanceof Bytes) {
return compareTo((Bytes)right_obj) == 0;
}
return false;
}
/**
* @see Object#toString()
*/
@Override
public String toString() {
return Bytes.toString(bytes, offset, length);
}
/**
* @param array List of byte [].
* @return Array of byte [].
*/
public static byte [][] toArray(final List<byte []> array) {
// List#toArray doesn't work on lists of byte [].
byte[][] results = new byte[array.size()][];
for (int i = 0; i < array.size(); i++) {
results[i] = array.get(i);
}
return results;
}
/**
* Returns a copy of the bytes referred to by this writable
*/
public byte[] copyBytes() {
return Arrays.copyOfRange(bytes, offset, offset+length);
}
/**
* Byte array comparator class.
*/
@InterfaceAudience.Public
public static class ByteArrayComparator implements RawComparator<byte []> {
/**
* Constructor
*/
public ByteArrayComparator() {
super();
}
@Override
public int compare(byte [] left, byte [] right) {
return compareTo(left, right);
}
@Override
public int compare(byte [] b1, int s1, int l1, byte [] b2, int s2, int l2) {
return LexicographicalComparerHolder.BEST_COMPARER.
compareTo(b1, s1, l1, b2, s2, l2);
}
}
/**
* A {@link ByteArrayComparator} that treats the empty array as the largest value.
* This is useful for comparing row end keys for regions.
*/
// TODO: unfortunately, HBase uses byte[0] as both start and end keys for region
// boundaries. Thus semantically, we should treat empty byte array as the smallest value
// while comparing row keys, start keys etc; but as the largest value for comparing
// region boundaries for endKeys.
@InterfaceAudience.Public
public static class RowEndKeyComparator extends ByteArrayComparator {
@Override
public int compare(byte[] left, byte[] right) {
return compare(left, 0, left.length, right, 0, right.length);
}
@Override
public int compare(byte[] b1, int s1, int l1, byte[] b2, int s2, int l2) {
if (b1 == b2 && s1 == s2 && l1 == l2) {
return 0;
}
if (l1 == 0) {
return l2; //0 or positive
}
if (l2 == 0) {
return -1;
}
return super.compare(b1, s1, l1, b2, s2, l2);
}
}
/**
* Pass this to TreeMaps where byte [] are keys.
*/
public final static Comparator<byte []> BYTES_COMPARATOR = new ByteArrayComparator();
/**
* Use comparing byte arrays, byte-by-byte
*/
public final static RawComparator<byte []> BYTES_RAWCOMPARATOR = new ByteArrayComparator();
/**
* Read byte-array written with a WritableableUtils.vint prefix.
* @param in Input to read from.
* @return byte array read off <code>in</code>
* @throws IOException e
*/
public static byte [] readByteArray(final DataInput in)
throws IOException {
int len = WritableUtils.readVInt(in);
if (len < 0) {
throw new NegativeArraySizeException(Integer.toString(len));
}
byte [] result = new byte[len];
in.readFully(result, 0, len);
return result;
}
/**
* Read byte-array written with a WritableableUtils.vint prefix.
* IOException is converted to a RuntimeException.
* @param in Input to read from.
* @return byte array read off <code>in</code>
*/
public static byte [] readByteArrayThrowsRuntime(final DataInput in) {
try {
return readByteArray(in);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
/**
* Write byte-array with a WritableableUtils.vint prefix.
* @param out output stream to be written to
* @param b array to write
* @throws IOException e
*/
public static void writeByteArray(final DataOutput out, final byte [] b)
throws IOException {
if(b == null) {
WritableUtils.writeVInt(out, 0);
} else {
writeByteArray(out, b, 0, b.length);
}
}
/**
* Write byte-array to out with a vint length prefix.
* @param out output stream
* @param b array
* @param offset offset into array
* @param length length past offset
* @throws IOException e
*/
public static void writeByteArray(final DataOutput out, final byte [] b,
final int offset, final int length)
throws IOException {
WritableUtils.writeVInt(out, length);
out.write(b, offset, length);
}
/**
* Write byte-array from src to tgt with a vint length prefix.
* @param tgt target array
* @param tgtOffset offset into target array
* @param src source array
* @param srcOffset source offset
* @param srcLength source length
* @return New offset in src array.
*/
public static int writeByteArray(final byte [] tgt, final int tgtOffset,
final byte [] src, final int srcOffset, final int srcLength) {
byte [] vint = vintToBytes(srcLength);
System.arraycopy(vint, 0, tgt, tgtOffset, vint.length);
int offset = tgtOffset + vint.length;
System.arraycopy(src, srcOffset, tgt, offset, srcLength);
return offset + srcLength;
}
/**
* Put bytes at the specified byte array position.
* @param tgtBytes the byte array
* @param tgtOffset position in the array
* @param srcBytes array to write out
* @param srcOffset source offset
* @param srcLength source length
* @return incremented offset
*/
public static int putBytes(byte[] tgtBytes, int tgtOffset, byte[] srcBytes,
int srcOffset, int srcLength) {
System.arraycopy(srcBytes, srcOffset, tgtBytes, tgtOffset, srcLength);
return tgtOffset + srcLength;
}
/**
* Write a single byte out to the specified byte array position.
* @param bytes the byte array
* @param offset position in the array
* @param b byte to write out
* @return incremented offset
*/
public static int putByte(byte[] bytes, int offset, byte b) {
bytes[offset] = b;
return offset + 1;
}
/**
* Add the whole content of the ByteBuffer to the bytes arrays. The ByteBuffer is modified.
* @param bytes the byte array
* @param offset position in the array
* @param buf ByteBuffer to write out
* @return incremented offset
*/
public static int putByteBuffer(byte[] bytes, int offset, ByteBuffer buf) {
int len = buf.remaining();
buf.get(bytes, offset, len);
return offset + len;
}
/**
* Returns a new byte array, copied from the given {@code buf},
* from the index 0 (inclusive) to the limit (exclusive),
* regardless of the current position.
* The position and the other index parameters are not changed.
*
* @param buf a byte buffer
* @return the byte array
* @see #getBytes(ByteBuffer)
*/
public static byte[] toBytes(ByteBuffer buf) {
ByteBuffer dup = buf.duplicate();
dup.position(0);
return readBytes(dup);
}
private static byte[] readBytes(ByteBuffer buf) {
byte [] result = new byte[buf.remaining()];
buf.get(result);
return result;
}
/**
* @param b Presumed UTF-8 encoded byte array.
* @return String made from <code>b</code>
*/
public static String toString(final byte [] b) {
if (b == null) {
return null;
}
return toString(b, 0, b.length);
}
/**
* Joins two byte arrays together using a separator.
* @param b1 The first byte array.
* @param sep The separator to use.
* @param b2 The second byte array.
*/
public static String toString(final byte [] b1,
String sep,
final byte [] b2) {
return toString(b1, 0, b1.length) + sep + toString(b2, 0, b2.length);
}
/**
* This method will convert utf8 encoded bytes into a string. If
* the given byte array is null, this method will return null.
*
* @param b Presumed UTF-8 encoded byte array.
* @param off offset into array
* @return String made from <code>b</code> or null
*/
public static String toString(final byte[] b, int off) {
if (b == null) {
return null;
}
int len = b.length - off;
if (len <= 0) {
return "";
}
try {
return new String(b, off, len, UTF8_CSN);
} catch (UnsupportedEncodingException e) {
// should never happen!
throw new IllegalArgumentException("UTF8 encoding is not supported", e);
}
}
/**
* This method will convert utf8 encoded bytes into a string. If
* the given byte array is null, this method will return null.
*
* @param b Presumed UTF-8 encoded byte array.
* @param off offset into array
* @param len length of utf-8 sequence
* @return String made from <code>b</code> or null
*/
public static String toString(final byte[] b, int off, int len) {
if (b == null) {
return null;
}
if (len == 0) {
return "";
}
try {
return new String(b, off, len, UTF8_CSN);
} catch (UnsupportedEncodingException e) {
// should never happen!
throw new IllegalArgumentException("UTF8 encoding is not supported", e);
}
}
/**
* Write a printable representation of a byte array.
*
* @param b byte array
* @return string
* @see #toStringBinary(byte[], int, int)
*/
public static String toStringBinary(final byte [] b) {
if (b == null)
return "null";
return toStringBinary(b, 0, b.length);
}
/**
* Converts the given byte buffer to a printable representation,
* from the index 0 (inclusive) to the limit (exclusive),
* regardless of the current position.
* The position and the other index parameters are not changed.
*
* @param buf a byte buffer
* @return a string representation of the buffer's binary contents
* @see #toBytes(ByteBuffer)
* @see #getBytes(ByteBuffer)
*/
public static String toStringBinary(ByteBuffer buf) {
if (buf == null)
return "null";
if (buf.hasArray()) {
return toStringBinary(buf.array(), buf.arrayOffset(), buf.limit());
}
return toStringBinary(toBytes(buf));
}
private static final char[] HEX_CHARS_UPPER = {
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F'
};
/**
* Write a printable representation of a byte array. Non-printable
* characters are hex escaped in the format \\x%02X, eg:
* \x00 \x05 etc
*
* @param b array to write out
* @param off offset to start at
* @param len length to write
* @return string output
*/
public static String toStringBinary(final byte [] b, int off, int len) {
StringBuilder result = new StringBuilder();
// Just in case we are passed a 'len' that is > buffer length...
if (off >= b.length) return result.toString();
if (off + len > b.length) len = b.length - off;
for (int i = off; i < off + len ; ++i) {
int ch = b[i] & 0xFF;
if (ch >= ' ' && ch <= '~' && ch != '\\') {
result.append((char)ch);
} else {
result.append("\\x");
result.append(HEX_CHARS_UPPER[ch / 0x10]);
result.append(HEX_CHARS_UPPER[ch % 0x10]);
}
}
return result.toString();
}
private static boolean isHexDigit(char c) {
return
(c >= 'A' && c <= 'F') ||
(c >= '0' && c <= '9');
}
/**
* Takes a ASCII digit in the range A-F0-9 and returns
* the corresponding integer/ordinal value.
* @param ch The hex digit.
* @return The converted hex value as a byte.
*/
public static byte toBinaryFromHex(byte ch) {
if (ch >= 'A' && ch <= 'F')
return (byte) ((byte)10 + (byte) (ch - 'A'));
// else
return (byte) (ch - '0');
}
public static byte [] toBytesBinary(String in) {
// this may be bigger than we need, but let's be safe.
byte [] b = new byte[in.length()];
int size = 0;
for (int i = 0; i < in.length(); ++i) {
char ch = in.charAt(i);
if (ch == '\\' && in.length() > i+1 && in.charAt(i+1) == 'x') {
// ok, take next 2 hex digits.
char hd1 = in.charAt(i+2);
char hd2 = in.charAt(i+3);
// they need to be A-F0-9:
if (!isHexDigit(hd1) ||
!isHexDigit(hd2)) {
// bogus escape code, ignore:
continue;
}
// turn hex ASCII digit -> number
byte d = (byte) ((toBinaryFromHex((byte)hd1) << 4) + toBinaryFromHex((byte)hd2));
b[size++] = d;
i += 3; // skip 3
} else {
b[size++] = (byte) ch;
}
}
// resize:
byte [] b2 = new byte[size];
System.arraycopy(b, 0, b2, 0, size);
return b2;
}
/**
* Converts a string to a UTF-8 byte array.
* @param s string
* @return the byte array
*/
public static byte[] toBytes(String s) {
try {
return s.getBytes(UTF8_CSN);
} catch (UnsupportedEncodingException e) {
// should never happen!
throw new IllegalArgumentException("UTF8 decoding is not supported", e);
}
}
/**
* Convert a boolean to a byte array. True becomes -1
* and false becomes 0.
*
* @param b value
* @return <code>b</code> encoded in a byte array.
*/
public static byte [] toBytes(final boolean b) {
return new byte[] { b ? (byte) -1 : (byte) 0 };
}
/**
* Reverses {@link #toBytes(boolean)}
* @param b array
* @return True or false.
*/
public static boolean toBoolean(final byte [] b) {
if (b.length != 1) {
throw new IllegalArgumentException("Array has wrong size: " + b.length);
}
return b[0] != (byte) 0;
}
/**
* Convert a long value to a byte array using big-endian.
*
* @param val value to convert
* @return the byte array
*/
public static byte[] toBytes(long val) {
byte [] b = new byte[8];
for (int i = 7; i > 0; i--) {
b[i] = (byte) val;
val >>>= 8;
}
b[0] = (byte) val;
return b;
}
/**
* Converts a byte array to a long value. Reverses
* {@link #toBytes(long)}
* @param bytes array
* @return the long value
*/
public static long toLong(byte[] bytes) {
return toLong(bytes, 0, SIZEOF_LONG);
}
/**
* Converts a byte array to a long value. Assumes there will be
* {@link #SIZEOF_LONG} bytes available.
*
* @param bytes bytes
* @param offset offset
* @return the long value
*/
public static long toLong(byte[] bytes, int offset) {
return toLong(bytes, offset, SIZEOF_LONG);
}
/**
* Converts a byte array to a long value.
*
* @param bytes array of bytes
* @param offset offset into array
* @param length length of data (must be {@link #SIZEOF_LONG})
* @return the long value
* @throws IllegalArgumentException if length is not {@link #SIZEOF_LONG} or
* if there's not enough room in the array at the offset indicated.
*/
public static long toLong(byte[] bytes, int offset, final int length) {
if (length != SIZEOF_LONG || offset + length > bytes.length) {
throw explainWrongLengthOrOffset(bytes, offset, length, SIZEOF_LONG);
}
return ConverterHolder.BEST_CONVERTER.toLong(bytes, offset, length);
}
private static IllegalArgumentException
explainWrongLengthOrOffset(final byte[] bytes,
final int offset,
final int length,
final int expectedLength) {
String reason;
if (length != expectedLength) {
reason = "Wrong length: " + length + ", expected " + expectedLength;
} else {
reason = "offset (" + offset + ") + length (" + length + ") exceed the"
+ " capacity of the array: " + bytes.length;
}
return new IllegalArgumentException(reason);
}
/**
* Put a long value out to the specified byte array position.
* @param bytes the byte array
* @param offset position in the array
* @param val long to write out
* @return incremented offset
* @throws IllegalArgumentException if the byte array given doesn't have
* enough room at the offset specified.
*/
public static int putLong(byte[] bytes, int offset, long val) {
if (bytes.length - offset < SIZEOF_LONG) {
throw new IllegalArgumentException("Not enough room to put a long at"
+ " offset " + offset + " in a " + bytes.length + " byte array");
}
return ConverterHolder.BEST_CONVERTER.putLong(bytes, offset, val);
}
/**
* Presumes float encoded as IEEE 754 floating-point "single format"
* @param bytes byte array
* @return Float made from passed byte array.
*/
public static float toFloat(byte [] bytes) {
return toFloat(bytes, 0);
}
/**
* Presumes float encoded as IEEE 754 floating-point "single format"
* @param bytes array to convert
* @param offset offset into array
* @return Float made from passed byte array.
*/
public static float toFloat(byte [] bytes, int offset) {
return Float.intBitsToFloat(toInt(bytes, offset, SIZEOF_INT));
}
/**
* @param bytes byte array
* @param offset offset to write to
* @param f float value
* @return New offset in <code>bytes</code>
*/
public static int putFloat(byte [] bytes, int offset, float f) {
return putInt(bytes, offset, Float.floatToRawIntBits(f));
}
/**
* @param f float value
* @return the float represented as byte []
*/
public static byte [] toBytes(final float f) {
// Encode it as int
return Bytes.toBytes(Float.floatToRawIntBits(f));
}
/**
* @param bytes byte array
* @return Return double made from passed bytes.
*/
public static double toDouble(final byte [] bytes) {
return toDouble(bytes, 0);
}
/**
* @param bytes byte array
* @param offset offset where double is
* @return Return double made from passed bytes.
*/
public static double toDouble(final byte [] bytes, final int offset) {
return Double.longBitsToDouble(toLong(bytes, offset, SIZEOF_LONG));
}
/**
* @param bytes byte array
* @param offset offset to write to
* @param d value
* @return New offset into array <code>bytes</code>
*/
public static int putDouble(byte [] bytes, int offset, double d) {
return putLong(bytes, offset, Double.doubleToLongBits(d));
}
/**
* Serialize a double as the IEEE 754 double format output. The resultant
* array will be 8 bytes long.
*
* @param d value
* @return the double represented as byte []
*/
public static byte [] toBytes(final double d) {
// Encode it as a long
return Bytes.toBytes(Double.doubleToRawLongBits(d));
}
/**
* Convert an int value to a byte array. Big-endian. Same as what DataOutputStream.writeInt
* does.
*
* @param val value
* @return the byte array
*/
public static byte[] toBytes(int val) {
byte [] b = new byte[4];
for(int i = 3; i > 0; i--) {
b[i] = (byte) val;
val >>>= 8;
}
b[0] = (byte) val;
return b;
}
/**
* Converts a byte array to an int value
* @param bytes byte array
* @return the int value
*/
public static int toInt(byte[] bytes) {
return toInt(bytes, 0, SIZEOF_INT);
}
/**
* Converts a byte array to an int value
* @param bytes byte array
* @param offset offset into array
* @return the int value
*/
public static int toInt(byte[] bytes, int offset) {
return toInt(bytes, offset, SIZEOF_INT);
}
/**
* Converts a byte array to an int value
* @param bytes byte array
* @param offset offset into array
* @param length length of int (has to be {@link #SIZEOF_INT})
* @return the int value
* @throws IllegalArgumentException if length is not {@link #SIZEOF_INT} or
* if there's not enough room in the array at the offset indicated.
*/
public static int toInt(byte[] bytes, int offset, final int length) {
if (length != SIZEOF_INT || offset + length > bytes.length) {
throw explainWrongLengthOrOffset(bytes, offset, length, SIZEOF_INT);
}
return ConverterHolder.BEST_CONVERTER.toInt(bytes, offset, length);
}
/**
* Converts a byte array to an int value
* @param bytes byte array
* @param offset offset into array
* @param length how many bytes should be considered for creating int
* @return the int value
* @throws IllegalArgumentException if there's not enough room in the array at the offset
* indicated.
*/
public static int readAsInt(byte[] bytes, int offset, final int length) {
if (offset + length > bytes.length) {
throw new IllegalArgumentException("offset (" + offset + ") + length (" + length
+ ") exceed the" + " capacity of the array: " + bytes.length);
}
int n = 0;
for(int i = offset; i < (offset + length); i++) {
n <<= 8;
n ^= bytes[i] & 0xFF;
}
return n;
}
/**
* Put an int value out to the specified byte array position.
* @param bytes the byte array
* @param offset position in the array
* @param val int to write out
* @return incremented offset
* @throws IllegalArgumentException if the byte array given doesn't have
* enough room at the offset specified.
*/
public static int putInt(byte[] bytes, int offset, int val) {
if (bytes.length - offset < SIZEOF_INT) {
throw new IllegalArgumentException("Not enough room to put an int at"
+ " offset " + offset + " in a " + bytes.length + " byte array");
}
return ConverterHolder.BEST_CONVERTER.putInt(bytes, offset, val);
}
/**
* Convert a short value to a byte array of {@link #SIZEOF_SHORT} bytes long.
* @param val value
* @return the byte array
*/
public static byte[] toBytes(short val) {
byte[] b = new byte[SIZEOF_SHORT];
b[1] = (byte) val;
val >>= 8;
b[0] = (byte) val;
return b;
}
/**
* Converts a byte array to a short value
* @param bytes byte array
* @return the short value
*/
public static short toShort(byte[] bytes) {
return toShort(bytes, 0, SIZEOF_SHORT);
}
/**
* Converts a byte array to a short value
* @param bytes byte array
* @param offset offset into array
* @return the short value
*/
public static short toShort(byte[] bytes, int offset) {
return toShort(bytes, offset, SIZEOF_SHORT);
}
/**
* Converts a byte array to a short value
* @param bytes byte array
* @param offset offset into array
* @param length length, has to be {@link #SIZEOF_SHORT}
* @return the short value
* @throws IllegalArgumentException if length is not {@link #SIZEOF_SHORT}
* or if there's not enough room in the array at the offset indicated.
*/
public static short toShort(byte[] bytes, int offset, final int length) {
if (length != SIZEOF_SHORT || offset + length > bytes.length) {
throw explainWrongLengthOrOffset(bytes, offset, length, SIZEOF_SHORT);
}
return ConverterHolder.BEST_CONVERTER.toShort(bytes, offset, length);
}
/**
* Returns a new byte array, copied from the given {@code buf},
* from the position (inclusive) to the limit (exclusive).
* The position and the other index parameters are not changed.
*
* @param buf a byte buffer
* @return the byte array
* @see #toBytes(ByteBuffer)
*/
public static byte[] getBytes(ByteBuffer buf) {
return readBytes(buf.duplicate());
}
/**
* Put a short value out to the specified byte array position.
* @param bytes the byte array
* @param offset position in the array
* @param val short to write out
* @return incremented offset
* @throws IllegalArgumentException if the byte array given doesn't have
* enough room at the offset specified.
*/
public static int putShort(byte[] bytes, int offset, short val) {
if (bytes.length - offset < SIZEOF_SHORT) {
throw new IllegalArgumentException("Not enough room to put a short at"
+ " offset " + offset + " in a " + bytes.length + " byte array");
}
return ConverterHolder.BEST_CONVERTER.putShort(bytes, offset, val);
}
/**
* Put an int value as short out to the specified byte array position. Only the lower 2 bytes of
* the short will be put into the array. The caller of the API need to make sure they will not
* loose the value by doing so. This is useful to store an unsigned short which is represented as
* int in other parts.
* @param bytes the byte array
* @param offset position in the array
* @param val value to write out
* @return incremented offset
* @throws IllegalArgumentException if the byte array given doesn't have
* enough room at the offset specified.
*/
public static int putAsShort(byte[] bytes, int offset, int val) {
if (bytes.length - offset < SIZEOF_SHORT) {
throw new IllegalArgumentException("Not enough room to put a short at"
+ " offset " + offset + " in a " + bytes.length + " byte array");
}
bytes[offset+1] = (byte) val;
val >>= 8;
bytes[offset] = (byte) val;
return offset + SIZEOF_SHORT;
}
/**
* Convert a BigDecimal value to a byte array
*
* @param val
* @return the byte array
*/
public static byte[] toBytes(BigDecimal val) {
byte[] valueBytes = val.unscaledValue().toByteArray();
byte[] result = new byte[valueBytes.length + SIZEOF_INT];
int offset = putInt(result, 0, val.scale());
putBytes(result, offset, valueBytes, 0, valueBytes.length);
return result;
}
/**
* Converts a byte array to a BigDecimal
*
* @param bytes
* @return the char value
*/
public static BigDecimal toBigDecimal(byte[] bytes) {
return toBigDecimal(bytes, 0, bytes.length);
}
/**
* Converts a byte array to a BigDecimal value
*
* @param bytes
* @param offset
* @param length
* @return the char value
*/
public static BigDecimal toBigDecimal(byte[] bytes, int offset, final int length) {
if (bytes == null || length < SIZEOF_INT + 1 ||
(offset + length > bytes.length)) {
return null;
}
int scale = toInt(bytes, offset);
byte[] tcBytes = new byte[length - SIZEOF_INT];
System.arraycopy(bytes, offset + SIZEOF_INT, tcBytes, 0, length - SIZEOF_INT);
return new BigDecimal(new BigInteger(tcBytes), scale);
}
/**
* Put a BigDecimal value out to the specified byte array position.
*
* @param bytes the byte array
* @param offset position in the array
* @param val BigDecimal to write out
* @return incremented offset
*/
public static int putBigDecimal(byte[] bytes, int offset, BigDecimal val) {
if (bytes == null) {
return offset;
}
byte[] valueBytes = val.unscaledValue().toByteArray();
byte[] result = new byte[valueBytes.length + SIZEOF_INT];
offset = putInt(result, offset, val.scale());
return putBytes(result, offset, valueBytes, 0, valueBytes.length);
}
/**
* @param vint Integer to make a vint of.
* @return Vint as bytes array.
*/
public static byte [] vintToBytes(final long vint) {
long i = vint;
int size = WritableUtils.getVIntSize(i);
byte [] result = new byte[size];
int offset = 0;
if (i >= -112 && i <= 127) {
result[offset] = (byte) i;
return result;
}
int len = -112;
if (i < 0) {
i ^= -1L; // take one's complement'
len = -120;
}
long tmp = i;
while (tmp != 0) {
tmp = tmp >> 8;
len--;
}
result[offset++] = (byte) len;
len = (len < -120) ? -(len + 120) : -(len + 112);
for (int idx = len; idx != 0; idx--) {
int shiftbits = (idx - 1) * 8;
long mask = 0xFFL << shiftbits;
result[offset++] = (byte)((i & mask) >> shiftbits);
}
return result;
}
/**
* @param buffer buffer to convert
* @return vint bytes as an integer.
*/
public static long bytesToVint(final byte [] buffer) {
int offset = 0;
byte firstByte = buffer[offset++];
int len = WritableUtils.decodeVIntSize(firstByte);
if (len == 1) {
return firstByte;
}
long i = 0;
for (int idx = 0; idx < len-1; idx++) {
byte b = buffer[offset++];
i = i << 8;
i = i | (b & 0xFF);
}
return (WritableUtils.isNegativeVInt(firstByte) ? ~i : i);
}
/**
* Reads a zero-compressed encoded long from input buffer and returns it.
* @param buffer Binary array
* @param offset Offset into array at which vint begins.
* @return deserialized long from buffer.
*/
public static long readAsVLong(final byte [] buffer, final int offset) {
byte firstByte = buffer[offset];
int len = WritableUtils.decodeVIntSize(firstByte);
if (len == 1) {
return firstByte;
}
long i = 0;
for (int idx = 0; idx < len-1; idx++) {
byte b = buffer[offset + 1 + idx];
i = i << 8;
i = i | (b & 0xFF);
}
return (WritableUtils.isNegativeVInt(firstByte) ? ~i : i);
}
/**
* @param left left operand
* @param right right operand
* @return 0 if equal, &lt; 0 if left is less than right, etc.
*/
public static int compareTo(final byte [] left, final byte [] right) {
return LexicographicalComparerHolder.BEST_COMPARER.
compareTo(left, 0, left == null? 0: left.length, right, 0, right == null? 0: right.length);
}
/**
* Lexicographically compare two arrays.
*
* @param buffer1 left operand
* @param buffer2 right operand
* @param offset1 Where to start comparing in the left buffer
* @param offset2 Where to start comparing in the right buffer
* @param length1 How much to compare from the left buffer
* @param length2 How much to compare from the right buffer
* @return 0 if equal, &lt; 0 if left is less than right, etc.
*/
public static int compareTo(byte[] buffer1, int offset1, int length1,
byte[] buffer2, int offset2, int length2) {
return LexicographicalComparerHolder.BEST_COMPARER.
compareTo(buffer1, offset1, length1, buffer2, offset2, length2);
}
interface Comparer<T> {
int compareTo(
T buffer1, int offset1, int length1, T buffer2, int offset2, int length2
);
}
static abstract class Converter {
abstract long toLong(byte[] bytes, int offset, int length);
abstract int putLong(byte[] bytes, int offset, long val);
abstract int toInt(byte[] bytes, int offset, final int length);
abstract int putInt(byte[] bytes, int offset, int val);
abstract short toShort(byte[] bytes, int offset, final int length);
abstract int putShort(byte[] bytes, int offset, short val);
}
static Comparer<byte[]> lexicographicalComparerJavaImpl() {
return LexicographicalComparerHolder.PureJavaComparer.INSTANCE;
}
static class ConverterHolder {
static final String UNSAFE_CONVERTER_NAME =
ConverterHolder.class.getName() + "$UnsafeConverter";
static final Converter BEST_CONVERTER = getBestConverter();
/**
* Returns the Unsafe-using Converter, or falls back to the pure-Java
* implementation if unable to do so.
*/
static Converter getBestConverter() {
try {
Class<?> theClass = Class.forName(UNSAFE_CONVERTER_NAME);
// yes, UnsafeComparer does implement Comparer<byte[]>
@SuppressWarnings("unchecked")
Converter converter = (Converter) theClass.getConstructor().newInstance();
return converter;
} catch (Throwable t) { // ensure we really catch *everything*
return PureJavaConverter.INSTANCE;
}
}
protected static final class PureJavaConverter extends Converter {
static final PureJavaConverter INSTANCE = new PureJavaConverter();
private PureJavaConverter() {}
@Override
long toLong(byte[] bytes, int offset, int length) {
long l = 0;
for(int i = offset; i < offset + length; i++) {
l <<= 8;
l ^= bytes[i] & 0xFF;
}
return l;
}
@Override
int putLong(byte[] bytes, int offset, long val) {
for(int i = offset + 7; i > offset; i--) {
bytes[i] = (byte) val;
val >>>= 8;
}
bytes[offset] = (byte) val;
return offset + SIZEOF_LONG;
}
@Override
int toInt(byte[] bytes, int offset, int length) {
int n = 0;
for(int i = offset; i < (offset + length); i++) {
n <<= 8;
n ^= bytes[i] & 0xFF;
}
return n;
}
@Override
int putInt(byte[] bytes, int offset, int val) {
for(int i= offset + 3; i > offset; i--) {
bytes[i] = (byte) val;
val >>>= 8;
}
bytes[offset] = (byte) val;
return offset + SIZEOF_INT;
}
@Override
short toShort(byte[] bytes, int offset, int length) {
short n = 0;
n = (short) ((n ^ bytes[offset]) & 0xFF);
n = (short) (n << 8);
n ^= (short) (bytes[offset+1] & 0xFF);
return n;
}
@Override
int putShort(byte[] bytes, int offset, short val) {
bytes[offset+1] = (byte) val;
val >>= 8;
bytes[offset] = (byte) val;
return offset + SIZEOF_SHORT;
}
}
protected static final class UnsafeConverter extends Converter {
static final Unsafe theUnsafe;
public UnsafeConverter() {}
static {
if (UNSAFE_UNALIGNED) {
theUnsafe = UnsafeAccess.theUnsafe;
} else {
// It doesn't matter what we throw;
// it's swallowed in getBestComparer().
throw new Error();
}
// sanity check - this should never fail
if (theUnsafe.arrayIndexScale(byte[].class) != 1) {
throw new AssertionError();
}
}
@Override
long toLong(byte[] bytes, int offset, int length) {
return UnsafeAccess.toLong(bytes, offset);
}
@Override
int putLong(byte[] bytes, int offset, long val) {
return UnsafeAccess.putLong(bytes, offset, val);
}
@Override
int toInt(byte[] bytes, int offset, int length) {
return UnsafeAccess.toInt(bytes, offset);
}
@Override
int putInt(byte[] bytes, int offset, int val) {
return UnsafeAccess.putInt(bytes, offset, val);
}
@Override
short toShort(byte[] bytes, int offset, int length) {
return UnsafeAccess.toShort(bytes, offset);
}
@Override
int putShort(byte[] bytes, int offset, short val) {
return UnsafeAccess.putShort(bytes, offset, val);
}
}
}
/**
* Provides a lexicographical comparer implementation; either a Java
* implementation or a faster implementation based on {@link Unsafe}.
*
* <p>Uses reflection to gracefully fall back to the Java implementation if
* {@code Unsafe} isn't available.
*/
static class LexicographicalComparerHolder {
static final String UNSAFE_COMPARER_NAME =
LexicographicalComparerHolder.class.getName() + "$UnsafeComparer";
static final Comparer<byte[]> BEST_COMPARER = getBestComparer();
/**
* Returns the Unsafe-using Comparer, or falls back to the pure-Java
* implementation if unable to do so.
*/
static Comparer<byte[]> getBestComparer() {
try {
Class<?> theClass = Class.forName(UNSAFE_COMPARER_NAME);
// yes, UnsafeComparer does implement Comparer<byte[]>
@SuppressWarnings("unchecked")
Comparer<byte[]> comparer =
(Comparer<byte[]>) theClass.getEnumConstants()[0];
return comparer;
} catch (Throwable t) { // ensure we really catch *everything*
return lexicographicalComparerJavaImpl();
}
}
enum PureJavaComparer implements Comparer<byte[]> {
INSTANCE;
@Override
public int compareTo(byte[] buffer1, int offset1, int length1,
byte[] buffer2, int offset2, int length2) {
// Short circuit equal case
if (buffer1 == buffer2 &&
offset1 == offset2 &&
length1 == length2) {
return 0;
}
// Bring WritableComparator code local
int end1 = offset1 + length1;
int end2 = offset2 + length2;
for (int i = offset1, j = offset2; i < end1 && j < end2; i++, j++) {
int a = (buffer1[i] & 0xff);
int b = (buffer2[j] & 0xff);
if (a != b) {
return a - b;
}
}
return length1 - length2;
}
}
enum UnsafeComparer implements Comparer<byte[]> {
INSTANCE;
static final Unsafe theUnsafe;
static {
if (UNSAFE_UNALIGNED) {
theUnsafe = UnsafeAccess.theUnsafe;
} else {
// It doesn't matter what we throw;
// it's swallowed in getBestComparer().
throw new Error();
}
// sanity check - this should never fail
if (theUnsafe.arrayIndexScale(byte[].class) != 1) {
throw new AssertionError();
}
}
/**
* Lexicographically compare two arrays.
*
* @param buffer1 left operand
* @param buffer2 right operand
* @param offset1 Where to start comparing in the left buffer
* @param offset2 Where to start comparing in the right buffer
* @param length1 How much to compare from the left buffer
* @param length2 How much to compare from the right buffer
* @return 0 if equal, < 0 if left is less than right, etc.
*/
@Override
public int compareTo(byte[] buffer1, int offset1, int length1,
byte[] buffer2, int offset2, int length2) {
// Short circuit equal case
if (buffer1 == buffer2 &&
offset1 == offset2 &&
length1 == length2) {
return 0;
}
final int stride = 8;
final int minLength = Math.min(length1, length2);
int strideLimit = minLength & ~(stride - 1);
final long offset1Adj = offset1 + UnsafeAccess.BYTE_ARRAY_BASE_OFFSET;
final long offset2Adj = offset2 + UnsafeAccess.BYTE_ARRAY_BASE_OFFSET;
int i;
/*
* Compare 8 bytes at a time. Benchmarking on x86 shows a stride of 8 bytes is no slower
* than 4 bytes even on 32-bit. On the other hand, it is substantially faster on 64-bit.
*/
for (i = 0; i < strideLimit; i += stride) {
long lw = theUnsafe.getLong(buffer1, offset1Adj + i);
long rw = theUnsafe.getLong(buffer2, offset2Adj + i);
if (lw != rw) {
if(!UnsafeAccess.LITTLE_ENDIAN) {
return ((lw + Long.MIN_VALUE) < (rw + Long.MIN_VALUE)) ? -1 : 1;
}
/*
* We want to compare only the first index where left[index] != right[index]. This
* corresponds to the least significant nonzero byte in lw ^ rw, since lw and rw are
* little-endian. Long.numberOfTrailingZeros(diff) tells us the least significant
* nonzero bit, and zeroing out the first three bits of L.nTZ gives us the shift to get
* that least significant nonzero byte. This comparison logic is based on UnsignedBytes
* comparator from guava v21
*/
int n = Long.numberOfTrailingZeros(lw ^ rw) & ~0x7;
return ((int) ((lw >>> n) & 0xFF)) - ((int) ((rw >>> n) & 0xFF));
}
}
// The epilogue to cover the last (minLength % stride) elements.
for (; i < minLength; i++) {
int a = (buffer1[offset1 + i] & 0xFF);
int b = (buffer2[offset2 + i] & 0xFF);
if (a != b) {
return a - b;
}
}
return length1 - length2;
}
}
}
/**
* @param left left operand
* @param right right operand
* @return True if equal
*/
public static boolean equals(final byte [] left, final byte [] right) {
// Could use Arrays.equals?
//noinspection SimplifiableConditionalExpression
if (left == right) return true;
if (left == null || right == null) return false;
if (left.length != right.length) return false;
if (left.length == 0) return true;
// Since we're often comparing adjacent sorted data,
// it's usual to have equal arrays except for the very last byte
// so check that first
if (left[left.length - 1] != right[right.length - 1]) return false;
return compareTo(left, right) == 0;
}
public static boolean equals(final byte[] left, int leftOffset, int leftLen,
final byte[] right, int rightOffset, int rightLen) {
// short circuit case
if (left == right &&
leftOffset == rightOffset &&
leftLen == rightLen) {
return true;
}
// different lengths fast check
if (leftLen != rightLen) {
return false;
}
if (leftLen == 0) {
return true;
}
// Since we're often comparing adjacent sorted data,
// it's usual to have equal arrays except for the very last byte
// so check that first
if (left[leftOffset + leftLen - 1] != right[rightOffset + rightLen - 1]) return false;
return LexicographicalComparerHolder.BEST_COMPARER.
compareTo(left, leftOffset, leftLen, right, rightOffset, rightLen) == 0;
}
/**
* @param a left operand
* @param buf right operand
* @return True if equal
*/
public static boolean equals(byte[] a, ByteBuffer buf) {
if (a == null) return buf == null;
if (buf == null) return false;
if (a.length != buf.remaining()) return false;
// Thou shalt not modify the original byte buffer in what should be read only operations.
ByteBuffer b = buf.duplicate();
for (byte anA : a) {
if (anA != b.get()) {
return false;
}
}
return true;
}
/**
* Return true if the byte array on the right is a prefix of the byte
* array on the left.
*/
public static boolean startsWith(byte[] bytes, byte[] prefix) {
return bytes != null && prefix != null &&
bytes.length >= prefix.length &&
LexicographicalComparerHolder.BEST_COMPARER.
compareTo(bytes, 0, prefix.length, prefix, 0, prefix.length) == 0;
}
/**
* @param b bytes to hash
* @return Runs {@link WritableComparator#hashBytes(byte[], int)} on the
* passed in array. This method is what {@link org.apache.hadoop.io.Text}
* use calculating hash code.
*/
public static int hashCode(final byte [] b) {
return hashCode(b, b.length);
}
/**
* @param b value
* @param length length of the value
* @return Runs {@link WritableComparator#hashBytes(byte[], int)} on the
* passed in array. This method is what {@link org.apache.hadoop.io.Text}
* use calculating hash code.
*/
public static int hashCode(final byte [] b, final int length) {
return WritableComparator.hashBytes(b, length);
}
/**
* @param b bytes to hash
* @return A hash of <code>b</code> as an Integer that can be used as key in
* Maps.
*/
public static Integer mapKey(final byte [] b) {
return hashCode(b);
}
/**
* @param b bytes to hash
* @param length length to hash
* @return A hash of <code>b</code> as an Integer that can be used as key in
* Maps.
*/
public static Integer mapKey(final byte [] b, final int length) {
return hashCode(b, length);
}
/**
* @param a lower half
* @param b upper half
* @return New array that has a in lower half and b in upper half.
*/
public static byte [] add(final byte [] a, final byte [] b) {
return add(a, b, EMPTY_BYTE_ARRAY);
}
/**
* @param a first third
* @param b second third
* @param c third third
* @return New array made from a, b and c
*/
public static byte [] add(final byte [] a, final byte [] b, final byte [] c) {
byte [] result = new byte[a.length + b.length + c.length];
System.arraycopy(a, 0, result, 0, a.length);
System.arraycopy(b, 0, result, a.length, b.length);
System.arraycopy(c, 0, result, a.length + b.length, c.length);
return result;
}
/**
* @param arrays all the arrays to concatenate together.
* @return New array made from the concatenation of the given arrays.
*/
public static byte [] add(final byte [][] arrays) {
int length = 0;
for (int i = 0; i < arrays.length; i++) {
length += arrays[i].length;
}
byte [] result = new byte[length];
int index = 0;
for (int i = 0; i < arrays.length; i++) {
System.arraycopy(arrays[i], 0, result, index, arrays[i].length);
index += arrays[i].length;
}
return result;
}
/**
* @param a array
* @param length amount of bytes to grab
* @return First <code>length</code> bytes from <code>a</code>
*/
public static byte [] head(final byte [] a, final int length) {
if (a.length < length) {
return null;
}
byte [] result = new byte[length];
System.arraycopy(a, 0, result, 0, length);
return result;
}
/**
* @param a array
* @param length amount of bytes to snarf
* @return Last <code>length</code> bytes from <code>a</code>
*/
public static byte [] tail(final byte [] a, final int length) {
if (a.length < length) {
return null;
}
byte [] result = new byte[length];
System.arraycopy(a, a.length - length, result, 0, length);
return result;
}
/**
* @param a array
* @param length new array size
* @return Value in <code>a</code> plus <code>length</code> prepended 0 bytes
*/
public static byte [] padHead(final byte [] a, final int length) {
byte [] padding = new byte[length];
for (int i = 0; i < length; i++) {
padding[i] = 0;
}
return add(padding,a);
}
/**
* @param a array
* @param length new array size
* @return Value in <code>a</code> plus <code>length</code> appended 0 bytes
*/
public static byte [] padTail(final byte [] a, final int length) {
byte [] padding = new byte[length];
for (int i = 0; i < length; i++) {
padding[i] = 0;
}
return add(a,padding);
}
/**
* Split passed range. Expensive operation relatively. Uses BigInteger math.
* Useful splitting ranges for MapReduce jobs.
* @param a Beginning of range
* @param b End of range
* @param num Number of times to split range. Pass 1 if you want to split
* the range in two; i.e. one split.
* @return Array of dividing values
*/
public static byte [][] split(final byte [] a, final byte [] b, final int num) {
return split(a, b, false, num);
}
/**
* Split passed range. Expensive operation relatively. Uses BigInteger math.
* Useful splitting ranges for MapReduce jobs.
* @param a Beginning of range
* @param b End of range
* @param inclusive Whether the end of range is prefix-inclusive or is
* considered an exclusive boundary. Automatic splits are generally exclusive
* and manual splits with an explicit range utilize an inclusive end of range.
* @param num Number of times to split range. Pass 1 if you want to split
* the range in two; i.e. one split.
* @return Array of dividing values
*/
public static byte[][] split(final byte[] a, final byte[] b,
boolean inclusive, final int num) {
byte[][] ret = new byte[num + 2][];
int i = 0;
Iterable<byte[]> iter = iterateOnSplits(a, b, inclusive, num);
if (iter == null)
return null;
for (byte[] elem : iter) {
ret[i++] = elem;
}
return ret;
}
/**
* Iterate over keys within the passed range, splitting at an [a,b) boundary.
*/
public static Iterable<byte[]> iterateOnSplits(final byte[] a,
final byte[] b, final int num)
{
return iterateOnSplits(a, b, false, num);
}
/**
* Iterate over keys within the passed range.
*/
public static Iterable<byte[]> iterateOnSplits(
final byte[] a, final byte[]b, boolean inclusive, final int num)
{
byte [] aPadded;
byte [] bPadded;
if (a.length < b.length) {
aPadded = padTail(a, b.length - a.length);
bPadded = b;
} else if (b.length < a.length) {
aPadded = a;
bPadded = padTail(b, a.length - b.length);
} else {
aPadded = a;
bPadded = b;
}
if (compareTo(aPadded,bPadded) >= 0) {
throw new IllegalArgumentException("b <= a");
}
if (num <= 0) {
throw new IllegalArgumentException("num cannot be <= 0");
}
byte [] prependHeader = {1, 0};
final BigInteger startBI = new BigInteger(add(prependHeader, aPadded));
final BigInteger stopBI = new BigInteger(add(prependHeader, bPadded));
BigInteger diffBI = stopBI.subtract(startBI);
if (inclusive) {
diffBI = diffBI.add(BigInteger.ONE);
}
final BigInteger splitsBI = BigInteger.valueOf(num + 1);
//when diffBI < splitBI, use an additional byte to increase diffBI
if(diffBI.compareTo(splitsBI) < 0) {
byte[] aPaddedAdditional = new byte[aPadded.length+1];
byte[] bPaddedAdditional = new byte[bPadded.length+1];
for (int i = 0; i < aPadded.length; i++){
aPaddedAdditional[i] = aPadded[i];
}
for (int j = 0; j < bPadded.length; j++){
bPaddedAdditional[j] = bPadded[j];
}
aPaddedAdditional[aPadded.length] = 0;
bPaddedAdditional[bPadded.length] = 0;
return iterateOnSplits(aPaddedAdditional, bPaddedAdditional, inclusive, num);
}
final BigInteger intervalBI;
try {
intervalBI = diffBI.divide(splitsBI);
} catch(Exception e) {
LOG.error("Exception caught during division", e);
return null;
}
final Iterator<byte[]> iterator = new Iterator<byte[]>() {
private int i = -1;
@Override
public boolean hasNext() {
return i < num+1;
}
@Override
public byte[] next() {
i++;
if (i == 0) return a;
if (i == num + 1) return b;
BigInteger curBI = startBI.add(intervalBI.multiply(BigInteger.valueOf(i)));
byte [] padded = curBI.toByteArray();
if (padded[1] == 0)
padded = tail(padded, padded.length - 2);
else
padded = tail(padded, padded.length - 1);
return padded;
}
@Override
public void remove() {
throw new UnsupportedOperationException();
}
};
return new Iterable<byte[]>() {
@Override
public Iterator<byte[]> iterator() {
return iterator;
}
};
}
/**
* @param bytes array to hash
* @param offset offset to start from
* @param length length to hash
* */
public static int hashCode(byte[] bytes, int offset, int length) {
int hash = 1;
for (int i = offset; i < offset + length; i++)
hash = (31 * hash) + bytes[i];
return hash;
}
/**
* @param t operands
* @return Array of byte arrays made from passed array of Text
*/
public static byte [][] toByteArrays(final String [] t) {
byte [][] result = new byte[t.length][];
for (int i = 0; i < t.length; i++) {
result[i] = Bytes.toBytes(t[i]);
}
return result;
}
/**
* @param t operands
* @return Array of binary byte arrays made from passed array of binary strings
*/
public static byte[][] toBinaryByteArrays(final String[] t) {
byte[][] result = new byte[t.length][];
for (int i = 0; i < t.length; i++) {
result[i] = Bytes.toBytesBinary(t[i]);
}
return result;
}
/**
* @param column operand
* @return A byte array of a byte array where first and only entry is
* <code>column</code>
*/
public static byte [][] toByteArrays(final String column) {
return toByteArrays(toBytes(column));
}
/**
* @param column operand
* @return A byte array of a byte array where first and only entry is
* <code>column</code>
*/
public static byte [][] toByteArrays(final byte [] column) {
byte [][] result = new byte[1][];
result[0] = column;
return result;
}
/**
* Binary search for keys in indexes using Bytes.BYTES_RAWCOMPARATOR.
*
* @param arr array of byte arrays to search for
* @param key the key you want to find
* @param offset the offset in the key you want to find
* @param length the length of the key
* @return zero-based index of the key, if the key is present in the array.
* Otherwise, a value -(i + 1) such that the key is between arr[i -
* 1] and arr[i] non-inclusively, where i is in [0, i], if we define
* arr[-1] = -Inf and arr[N] = Inf for an N-element array. The above
* means that this function can return 2N + 1 different values
* ranging from -(N + 1) to N - 1.
*/
public static int binarySearch(byte[][] arr, byte[] key, int offset, int length) {
int low = 0;
int high = arr.length - 1;
while (low <= high) {
int mid = low + ((high - low) >> 1);
// we have to compare in this order, because the comparator order
// has special logic when the 'left side' is a special key.
int cmp = Bytes.BYTES_RAWCOMPARATOR
.compare(key, offset, length, arr[mid], 0, arr[mid].length);
// key lives above the midpoint
if (cmp > 0)
low = mid + 1;
// key lives below the midpoint
else if (cmp < 0)
high = mid - 1;
// BAM. how often does this really happen?
else
return mid;
}
return -(low + 1);
}
/**
* Binary search for keys in indexes.
*
* @param arr array of byte arrays to search for
* @param key the key you want to find
* @param comparator a comparator to compare.
* @return zero-based index of the key, if the key is present in the array.
* Otherwise, a value -(i + 1) such that the key is between arr[i -
* 1] and arr[i] non-inclusively, where i is in [0, i], if we define
* arr[-1] = -Inf and arr[N] = Inf for an N-element array. The above
* means that this function can return 2N + 1 different values
* ranging from -(N + 1) to N - 1.
* @return the index of the block
*/
public static int binarySearch(Cell[] arr, Cell key, CellComparator comparator) {
int low = 0;
int high = arr.length - 1;
while (low <= high) {
int mid = low + ((high - low) >> 1);
// we have to compare in this order, because the comparator order
// has special logic when the 'left side' is a special key.
int cmp = comparator.compare(key, arr[mid]);
// key lives above the midpoint
if (cmp > 0)
low = mid + 1;
// key lives below the midpoint
else if (cmp < 0)
high = mid - 1;
// BAM. how often does this really happen?
else
return mid;
}
return - (low+1);
}
/**
* Bytewise binary increment/deincrement of long contained in byte array
* on given amount.
*
* @param value - array of bytes containing long (length &lt;= SIZEOF_LONG)
* @param amount value will be incremented on (deincremented if negative)
* @return array of bytes containing incremented long (length == SIZEOF_LONG)
*/
public static byte [] incrementBytes(byte[] value, long amount)
{
byte[] val = value;
if (val.length < SIZEOF_LONG) {
// Hopefully this doesn't happen too often.
byte [] newvalue;
if (val[0] < 0) {
newvalue = new byte[]{-1, -1, -1, -1, -1, -1, -1, -1};
} else {
newvalue = new byte[SIZEOF_LONG];
}
System.arraycopy(val, 0, newvalue, newvalue.length - val.length,
val.length);
val = newvalue;
} else if (val.length > SIZEOF_LONG) {
throw new IllegalArgumentException("Increment Bytes - value too big: " +
val.length);
}
if(amount == 0) return val;
if(val[0] < 0){
return binaryIncrementNeg(val, amount);
}
return binaryIncrementPos(val, amount);
}
/* increment/deincrement for positive value */
private static byte [] binaryIncrementPos(byte [] value, long amount) {
long amo = amount;
int sign = 1;
if (amount < 0) {
amo = -amount;
sign = -1;
}
for(int i=0;i<value.length;i++) {
int cur = ((int)amo % 256) * sign;
amo = (amo >> 8);
int val = value[value.length-i-1] & 0x0ff;
int total = val + cur;
if(total > 255) {
amo += sign;
total %= 256;
} else if (total < 0) {
amo -= sign;
}
value[value.length-i-1] = (byte)total;
if (amo == 0) return value;
}
return value;
}
/* increment/deincrement for negative value */
private static byte [] binaryIncrementNeg(byte [] value, long amount) {
long amo = amount;
int sign = 1;
if (amount < 0) {
amo = -amount;
sign = -1;
}
for(int i=0;i<value.length;i++) {
int cur = ((int)amo % 256) * sign;
amo = (amo >> 8);
int val = ((~value[value.length-i-1]) & 0x0ff) + 1;
int total = cur - val;
if(total >= 0) {
amo += sign;
} else if (total < -256) {
amo -= sign;
total %= 256;
}
value[value.length-i-1] = (byte)total;
if (amo == 0) return value;
}
return value;
}
/**
* Writes a string as a fixed-size field, padded with zeros.
*/
public static void writeStringFixedSize(final DataOutput out, String s,
int size) throws IOException {
byte[] b = toBytes(s);
if (b.length > size) {
throw new IOException("Trying to write " + b.length + " bytes (" +
toStringBinary(b) + ") into a field of length " + size);
}
out.writeBytes(s);
for (int i = 0; i < size - s.length(); ++i)
out.writeByte(0);
}
/**
* Reads a fixed-size field and interprets it as a string padded with zeros.
*/
public static String readStringFixedSize(final DataInput in, int size)
throws IOException {
byte[] b = new byte[size];
in.readFully(b);
int n = b.length;
while (n > 0 && b[n - 1] == 0)
--n;
return toString(b, 0, n);
}
/**
* Copy the byte array given in parameter and return an instance
* of a new byte array with the same length and the same content.
* @param bytes the byte array to duplicate
* @return a copy of the given byte array
*/
public static byte [] copy(byte [] bytes) {
if (bytes == null) return null;
byte [] result = new byte[bytes.length];
System.arraycopy(bytes, 0, result, 0, bytes.length);
return result;
}
/**
* Copy the byte array given in parameter and return an instance
* of a new byte array with the same length and the same content.
* @param bytes the byte array to copy from
* @return a copy of the given designated byte array
* @param offset
* @param length
*/
public static byte [] copy(byte [] bytes, final int offset, final int length) {
if (bytes == null) return null;
byte [] result = new byte[length];
System.arraycopy(bytes, offset, result, 0, length);
return result;
}
/**
* Search sorted array "a" for byte "key". I can't remember if I wrote this or copied it from
* somewhere. (mcorgan)
* @param a Array to search. Entries must be sorted and unique.
* @param fromIndex First index inclusive of "a" to include in the search.
* @param toIndex Last index exclusive of "a" to include in the search.
* @param key The byte to search for.
* @return The index of key if found. If not found, return -(index + 1), where negative indicates
* "not found" and the "index + 1" handles the "-0" case.
*/
public static int unsignedBinarySearch(byte[] a, int fromIndex, int toIndex, byte key) {
int unsignedKey = key & 0xff;
int low = fromIndex;
int high = toIndex - 1;
while (low <= high) {
int mid = low + ((high - low) >> 1);
int midVal = a[mid] & 0xff;
if (midVal < unsignedKey) {
low = mid + 1;
} else if (midVal > unsignedKey) {
high = mid - 1;
} else {
return mid; // key found
}
}
return -(low + 1); // key not found.
}
/**
* Treat the byte[] as an unsigned series of bytes, most significant bits first. Start by adding
* 1 to the rightmost bit/byte and carry over all overflows to the more significant bits/bytes.
*
* @param input The byte[] to increment.
* @return The incremented copy of "in". May be same length or 1 byte longer.
*/
public static byte[] unsignedCopyAndIncrement(final byte[] input) {
byte[] copy = copy(input);
if (copy == null) {
throw new IllegalArgumentException("cannot increment null array");
}
for (int i = copy.length - 1; i >= 0; --i) {
if (copy[i] == -1) {// -1 is all 1-bits, which is the unsigned maximum
copy[i] = 0;
} else {
++copy[i];
return copy;
}
}
// we maxed out the array
byte[] out = new byte[copy.length + 1];
out[0] = 1;
System.arraycopy(copy, 0, out, 1, copy.length);
return out;
}
public static boolean equals(List<byte[]> a, List<byte[]> b) {
if (a == null) {
if (b == null) {
return true;
}
return false;
}
if (b == null) {
return false;
}
if (a.size() != b.size()) {
return false;
}
for (int i = 0; i < a.size(); ++i) {
if (!Bytes.equals(a.get(i), b.get(i))) {
return false;
}
}
return true;
}
public static boolean isSorted(Collection<byte[]> arrays) {
if (!CollectionUtils.isEmpty(arrays)) {
byte[] previous = new byte[0];
for (byte[] array : arrays) {
if (Bytes.compareTo(previous, array) > 0) {
return false;
}
previous = array;
}
}
return true;
}
public static List<byte[]> getUtf8ByteArrays(List<String> strings) {
if (CollectionUtils.isEmpty(strings)) {
return Collections.emptyList();
}
List<byte[]> byteArrays = new ArrayList<>(strings.size());
strings.forEach(s -> byteArrays.add(Bytes.toBytes(s)));
return byteArrays;
}
/**
* Returns the index of the first appearance of the value {@code target} in
* {@code array}.
*
* @param array an array of {@code byte} values, possibly empty
* @param target a primitive {@code byte} value
* @return the least index {@code i} for which {@code array[i] == target}, or
* {@code -1} if no such index exists.
*/
public static int indexOf(byte[] array, byte target) {
for (int i = 0; i < array.length; i++) {
if (array[i] == target) {
return i;
}
}
return -1;
}
/**
* Returns the start position of the first occurrence of the specified {@code
* target} within {@code array}, or {@code -1} if there is no such occurrence.
*
* <p>More formally, returns the lowest index {@code i} such that {@code
* java.util.Arrays.copyOfRange(array, i, i + target.length)} contains exactly
* the same elements as {@code target}.
*
* @param array the array to search for the sequence {@code target}
* @param target the array to search for as a sub-sequence of {@code array}
*/
public static int indexOf(byte[] array, byte[] target) {
checkNotNull(array, "array");
checkNotNull(target, "target");
if (target.length == 0) {
return 0;
}
outer:
for (int i = 0; i < array.length - target.length + 1; i++) {
for (int j = 0; j < target.length; j++) {
if (array[i + j] != target[j]) {
continue outer;
}
}
return i;
}
return -1;
}
/**
* @param array an array of {@code byte} values, possibly empty
* @param target a primitive {@code byte} value
* @return {@code true} if {@code target} is present as an element anywhere in {@code array}.
*/
public static boolean contains(byte[] array, byte target) {
return indexOf(array, target) > -1;
}
/**
* @param array an array of {@code byte} values, possibly empty
* @param target an array of {@code byte}
* @return {@code true} if {@code target} is present anywhere in {@code array}
*/
public static boolean contains(byte[] array, byte[] target) {
return indexOf(array, target) > -1;
}
/**
* Fill given array with zeros.
* @param b array which needs to be filled with zeros
*/
public static void zero(byte[] b) {
zero(b, 0, b.length);
}
/**
* Fill given array with zeros at the specified position.
* @param b
* @param offset
* @param length
*/
public static void zero(byte[] b, int offset, int length) {
checkPositionIndex(offset, b.length, "offset");
checkArgument(length > 0, "length must be greater than 0");
checkPositionIndex(offset + length, b.length, "offset + length");
Arrays.fill(b, offset, offset + length, (byte) 0);
}
private static final SecureRandom RNG = new SecureRandom();
/**
* Fill given array with random bytes.
* @param b array which needs to be filled with random bytes
*/
public static void random(byte[] b) {
RNG.nextBytes(b);
}
/**
* Fill given array with random bytes at the specified position.
* @param b
* @param offset
* @param length
*/
public static void random(byte[] b, int offset, int length) {
checkPositionIndex(offset, b.length, "offset");
checkArgument(length > 0, "length must be greater than 0");
checkPositionIndex(offset + length, b.length, "offset + length");
byte[] buf = new byte[length];
RNG.nextBytes(buf);
System.arraycopy(buf, 0, b, offset, length);
}
/**
* Create a max byte array with the specified max byte count
* @param maxByteCount the length of returned byte array
* @return the created max byte array
*/
public static byte[] createMaxByteArray(int maxByteCount) {
byte[] maxByteArray = new byte[maxByteCount];
for (int i = 0; i < maxByteArray.length; i++) {
maxByteArray[i] = (byte) 0xff;
}
return maxByteArray;
}
/**
* Create a byte array which is multiple given bytes
* @param srcBytes
* @param multiNum
* @return byte array
*/
public static byte[] multiple(byte[] srcBytes, int multiNum) {
if (multiNum <= 0) {
return new byte[0];
}
byte[] result = new byte[srcBytes.length * multiNum];
for (int i = 0; i < multiNum; i++) {
System.arraycopy(srcBytes, 0, result, i * srcBytes.length,
srcBytes.length);
}
return result;
}
private static final char[] HEX_CHARS = {
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'
};
/**
* Convert a byte range into a hex string
*/
public static String toHex(byte[] b, int offset, int length) {
checkArgument(length <= Integer.MAX_VALUE / 2);
int numChars = length * 2;
char[] ch = new char[numChars];
for (int i = 0; i < numChars; i += 2)
{
byte d = b[offset + i/2];
ch[i] = HEX_CHARS[(d >> 4) & 0x0F];
ch[i+1] = HEX_CHARS[d & 0x0F];
}
return new String(ch);
}
/**
* Convert a byte array into a hex string
*/
public static String toHex(byte[] b) {
return toHex(b, 0, b.length);
}
private static int hexCharToNibble(char ch) {
if (ch <= '9' && ch >= '0') {
return ch - '0';
} else if (ch >= 'a' && ch <= 'f') {
return ch - 'a' + 10;
} else if (ch >= 'A' && ch <= 'F') {
return ch - 'A' + 10;
}
throw new IllegalArgumentException("Invalid hex char: " + ch);
}
private static byte hexCharsToByte(char c1, char c2) {
return (byte) ((hexCharToNibble(c1) << 4) | hexCharToNibble(c2));
}
/**
* Create a byte array from a string of hash digits. The length of the
* string must be a multiple of 2
* @param hex
*/
public static byte[] fromHex(String hex) {
checkArgument(hex.length() % 2 == 0, "length must be a multiple of 2");
int len = hex.length();
byte[] b = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
b[i / 2] = hexCharsToByte(hex.charAt(i),hex.charAt(i+1));
}
return b;
}
/**
* @param b
* @param delimiter
* @return Index of delimiter having started from start of <code>b</code> moving rightward.
*/
public static int searchDelimiterIndex(final byte[] b, int offset, final int length,
final int delimiter) {
if (b == null) {
throw new IllegalArgumentException("Passed buffer is null");
}
int result = -1;
for (int i = offset; i < length + offset; i++) {
if (b[i] == delimiter) {
result = i;
break;
}
}
return result;
}
/**
* Find index of passed delimiter walking from end of buffer backwards.
*
* @param b
* @param delimiter
* @return Index of delimiter
*/
public static int searchDelimiterIndexInReverse(final byte[] b, final int offset,
final int length, final int delimiter) {
if (b == null) {
throw new IllegalArgumentException("Passed buffer is null");
}
int result = -1;
for (int i = (offset + length) - 1; i >= offset; i--) {
if (b[i] == delimiter) {
result = i;
break;
}
}
return result;
}
public static int findCommonPrefix(byte[] left, byte[] right, int leftLength, int rightLength,
int leftOffset, int rightOffset) {
int length = Math.min(leftLength, rightLength);
int result = 0;
while (result < length && left[leftOffset + result] == right[rightOffset + result]) {
result++;
}
return result;
}
}