| /* |
| * 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.fluo.api.data; |
| |
| import java.io.ByteArrayInputStream; |
| import java.io.DataInputStream; |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.io.Serializable; |
| import java.lang.ref.WeakReference; |
| import java.nio.ByteBuffer; |
| import java.nio.CharBuffer; |
| import java.nio.charset.Charset; |
| import java.nio.charset.StandardCharsets; |
| import java.util.Arrays; |
| import java.util.Objects; |
| |
| import com.google.common.base.Preconditions; |
| import com.google.common.primitives.UnsignedBytes; |
| |
| /** |
| * Represents bytes in Fluo. Bytes is an immutable wrapper around a byte array. Bytes always copies |
| * on creation and never lets its internal byte array escape. Its modeled after Java's String which |
| * is an immutable wrapper around a char array. It was created because there is nothing in Java like |
| * it at the moment. Its very nice having this immutable type, it avoids having to do defensive |
| * copies to ensure correctness. Maybe one day Java will have equivalents of String, StringBuilder, |
| * and Charsequence for bytes. |
| * |
| * <p> |
| * The reason Fluo did not use ByteBuffer is because its not immutable, even a read only ByteBuffer |
| * has a mutable position. This makes ByteBuffer unsuitable for place where an immutable data type |
| * is desirable, like a key for a map. |
| * |
| * <p> |
| * Bytes.EMPTY is used to represent a Bytes object with no data. |
| * |
| * @since 1.0.0 |
| */ |
| public final class Bytes implements Comparable<Bytes>, Serializable { |
| |
| private static final long serialVersionUID = 1L; |
| |
| private final byte[] data; |
| private final int offset; |
| private final int length; |
| |
| private transient WeakReference<String> utf8String; |
| |
| public static final Bytes EMPTY = new Bytes(new byte[0]); |
| |
| private int hashCode = 0; |
| |
| public Bytes() { |
| data = EMPTY.data; |
| offset = 0; |
| length = 0; |
| } |
| |
| private Bytes(byte[] data) { |
| this.data = data; |
| this.offset = 0; |
| this.length = data.length; |
| } |
| |
| private Bytes(byte[] data, String utf8String) { |
| this.data = data; |
| this.offset = 0; |
| this.length = data.length; |
| this.utf8String = new WeakReference<>(utf8String); |
| } |
| |
| private Bytes(byte[] data, int offset, int length) { |
| if (offset < 0 || offset > data.length || length < 0 || (offset + length) > data.length) { |
| throw new IndexOutOfBoundsException(" Bad offset and/or length data.length = " + data.length |
| + " offset = " + offset + " length = " + length); |
| } |
| this.data = data; |
| this.offset = offset; |
| this.length = length; |
| } |
| |
| /** |
| * Gets a byte within this sequence of bytes |
| * |
| * @param i index into sequence |
| * @return byte |
| * @throws IllegalArgumentException if i is out of range |
| */ |
| public byte byteAt(int i) { |
| |
| if (i < 0) { |
| throw new IndexOutOfBoundsException("i < 0, " + i); |
| } |
| |
| if (i >= length) { |
| throw new IndexOutOfBoundsException("i >= length, " + i + " >= " + length); |
| } |
| |
| return data[offset + i]; |
| } |
| |
| /** |
| * Gets the length of bytes |
| */ |
| public int length() { |
| return length; |
| } |
| |
| /** |
| * Returns a portion of the Bytes object |
| * |
| * @param start index of subsequence start (inclusive) |
| * @param end index of subsequence end (exclusive) |
| */ |
| public Bytes subSequence(int start, int end) { |
| if (start > end || start < 0 || end > length) { |
| throw new IndexOutOfBoundsException("Bad start and/end start = " + start + " end=" + end |
| + " offset=" + offset + " length=" + length); |
| } |
| return new Bytes(data, offset + start, end - start); |
| } |
| |
| /** |
| * Returns a byte array containing a copy of the bytes |
| */ |
| public byte[] toArray() { |
| byte[] copy = new byte[length]; |
| System.arraycopy(data, offset, copy, 0, length); |
| return copy; |
| } |
| |
| /** |
| * Creates UTF-8 String using Bytes data |
| */ |
| @Override |
| public String toString() { |
| if (utf8String != null) { |
| String s = utf8String.get(); |
| if (s != null) { |
| return s; |
| } |
| } |
| |
| String s = new String(data, offset, length, StandardCharsets.UTF_8); |
| utf8String = new WeakReference<>(s); |
| return s; |
| } |
| |
| /** |
| * @return A read only byte buffer thats backed by the internal byte array. |
| */ |
| public ByteBuffer toByteBuffer() { |
| return ByteBuffer.wrap(data, offset, length).asReadOnlyBuffer(); |
| } |
| |
| /** |
| * @return An input stream thats backed by the internal byte array |
| */ |
| public InputStream toInputStream() { |
| return new ByteArrayInputStream(data, offset, length); |
| } |
| |
| public void writeTo(OutputStream out) throws IOException { |
| // since Bytes is immutable, its important that we do not let the internal byte array escape |
| if (length <= 32) { |
| int end = offset + length; |
| for (int i = offset; i < end; i++) { |
| out.write(data[i]); |
| } |
| } else { |
| out.write(toArray()); |
| } |
| } |
| |
| /** |
| * Compares this to the passed bytes, byte by byte, returning a negative, zero, or positive result |
| * if the first sequence is less than, equal to, or greater than the second. The comparison is |
| * performed starting with the first byte of each sequence, and proceeds until a pair of bytes |
| * differs, or one sequence runs out of byte (is shorter). A shorter sequence is considered less |
| * than a longer one. |
| * |
| * @return comparison result |
| */ |
| @Override |
| public final int compareTo(Bytes other) { |
| if (this == other) { |
| return 0; |
| } else if (this.length == this.data.length && other.length == other.data.length) { |
| return UnsignedBytes.lexicographicalComparator().compare(this.data, other.data); |
| } else { |
| int minLen = Math.min(this.length, other.length); |
| for (int i = this.offset, j = other.offset; i < minLen; i++, j++) { |
| int a = (this.data[i] & 0xff); |
| int b = (other.data[j] & 0xff); |
| |
| if (a != b) { |
| return a - b; |
| } |
| } |
| return this.length - other.length; |
| } |
| } |
| |
| /** |
| * Returns true if this Bytes object equals another. |
| */ |
| @Override |
| public final boolean equals(Object other) { |
| |
| if (this == other) { |
| return true; |
| } |
| |
| if (other instanceof Bytes) { |
| Bytes ob = (Bytes) other; |
| |
| if (length != ob.length) { |
| return false; |
| } |
| |
| return compareTo(ob) == 0; |
| } |
| return false; |
| } |
| |
| @Override |
| public final int hashCode() { |
| if (hashCode == 0) { |
| int hash = 1; |
| int end = offset + length; |
| for (int i = offset; i < end; i++) { |
| hash = (31 * hash) + data[i]; |
| } |
| hashCode = hash; |
| } |
| return hashCode; |
| } |
| |
| /** |
| * Creates a Bytes object by copying the data of the given byte array |
| */ |
| public static final Bytes of(byte[] array) { |
| Objects.requireNonNull(array); |
| if (array.length == 0) { |
| return EMPTY; |
| } |
| byte[] copy = new byte[array.length]; |
| System.arraycopy(array, 0, copy, 0, array.length); |
| return new Bytes(copy); |
| } |
| |
| /** |
| * Creates a Bytes object by copying the data of a subsequence of the given byte array |
| * |
| * @param data Byte data |
| * @param offset Starting offset in byte array (inclusive) |
| * @param length Number of bytes to include |
| */ |
| public static final Bytes of(byte[] data, int offset, int length) { |
| Objects.requireNonNull(data); |
| if (length == 0) { |
| return EMPTY; |
| } |
| byte[] copy = new byte[length]; |
| System.arraycopy(data, offset, copy, 0, length); |
| return new Bytes(copy); |
| } |
| |
| /** |
| * Creates a Bytes object by copying the data of the given ByteBuffer. |
| * |
| * @param bb Data will be read from this ByteBuffer in such a way that its position is not |
| * changed. |
| */ |
| public static final Bytes of(ByteBuffer bb) { |
| Objects.requireNonNull(bb); |
| if (bb.remaining() == 0) { |
| return EMPTY; |
| } |
| byte[] data; |
| if (bb.hasArray()) { |
| data = |
| Arrays.copyOfRange(bb.array(), bb.position() + bb.arrayOffset(), |
| bb.limit() + bb.arrayOffset()); |
| } else { |
| data = new byte[bb.remaining()]; |
| // duplicate so that it does not change position |
| bb.duplicate().get(data); |
| } |
| return new Bytes(data); |
| } |
| |
| /** |
| * Creates a Bytes object by copying the data of the CharSequence and encoding it using UTF-8. |
| */ |
| public static final Bytes of(CharSequence cs) { |
| if (cs instanceof String) { |
| return of((String) cs); |
| } |
| |
| Objects.requireNonNull(cs); |
| if (cs.length() == 0) { |
| return EMPTY; |
| } |
| |
| ByteBuffer bb = StandardCharsets.UTF_8.encode(CharBuffer.wrap(cs)); |
| |
| if (bb.hasArray()) { |
| // this byte buffer has never escaped so can use its byte array directly |
| return new Bytes(bb.array(), bb.position() + bb.arrayOffset(), bb.limit()); |
| } else { |
| byte[] data = new byte[bb.remaining()]; |
| bb.get(data); |
| return new Bytes(data); |
| } |
| } |
| |
| /** |
| * Creates a Bytes object by copying the value of the given String |
| */ |
| public static final Bytes of(String s) { |
| Objects.requireNonNull(s); |
| if (s.length() == 0) { |
| return EMPTY; |
| } |
| byte[] data = s.getBytes(StandardCharsets.UTF_8); |
| return new Bytes(data, s); |
| } |
| |
| /** |
| * Creates a Bytes object by copying the value of the given String with a given charset |
| */ |
| public static final Bytes of(String s, Charset c) { |
| Objects.requireNonNull(s); |
| Objects.requireNonNull(c); |
| if (s.length() == 0) { |
| return EMPTY; |
| } |
| byte[] data = s.getBytes(c); |
| return new Bytes(data); |
| } |
| |
| /** |
| * Checks if this has the passed prefix |
| * |
| * @param prefix is a Bytes object to compare to this |
| * @return true or false |
| * @since 1.1.0 |
| */ |
| public boolean startsWith(Bytes prefix) { |
| Objects.requireNonNull(prefix, "startWith(Bytes prefix) cannot have null parameter"); |
| |
| if (prefix.length > this.length) { |
| return false; |
| } else { |
| int end = this.offset + prefix.length; |
| for (int i = this.offset, j = prefix.offset; i < end; i++, j++) { |
| if (this.data[i] != prefix.data[j]) { |
| return false; |
| } |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * Checks if this has the passed suffix |
| * |
| * @param suffix is a Bytes object to compare to this |
| * @return true or false |
| * @since 1.1.0 |
| */ |
| public boolean endsWith(Bytes suffix) { |
| Objects.requireNonNull(suffix, "endsWith(Bytes suffix) cannot have null parameter"); |
| int startOffset = this.length - suffix.length; |
| |
| if (startOffset < 0) { |
| return false; |
| } else { |
| int end = startOffset + this.offset + suffix.length; |
| for (int i = startOffset + this.offset, j = suffix.offset; i < end; i++, j++) { |
| if (this.data[i] != suffix.data[j]) { |
| return false; |
| } |
| } |
| } |
| return true; |
| } |
| |
| /** |
| * This class provides an easy, efficient, reusable mechanism for building immutable Bytes |
| * objects. |
| * |
| * @since 1.0.0 |
| */ |
| public static class BytesBuilder { |
| |
| private byte[] ba; |
| private int len; |
| |
| BytesBuilder(int initialCapacity) { |
| ba = new byte[initialCapacity]; |
| len = 0; |
| } |
| |
| BytesBuilder() { |
| this(32); |
| } |
| |
| private void ensureCapacity(int min) { |
| if (ba.length < min) { |
| int newLen = ba.length * 2; |
| if (newLen < min) { |
| newLen = min; |
| } |
| |
| ba = Arrays.copyOf(ba, newLen); |
| } |
| } |
| |
| public BytesBuilder append(CharSequence cs) { |
| if (cs instanceof String) { |
| return append((String) cs); |
| } |
| |
| |
| ByteBuffer bb = StandardCharsets.UTF_8.encode(CharBuffer.wrap(cs)); |
| |
| int length = bb.remaining(); |
| ensureCapacity(len + length); |
| bb.get(ba, len, length); |
| len += length; |
| return this; |
| } |
| |
| /** |
| * Converts string to bytes using UTF-8 encoding and appends bytes. |
| * |
| * @return self |
| */ |
| public BytesBuilder append(String s) { |
| return append(s.getBytes(StandardCharsets.UTF_8)); |
| } |
| |
| public BytesBuilder append(Bytes b) { |
| ensureCapacity(len + b.length); |
| System.arraycopy(b.data, b.offset, ba, len, b.length); |
| len += b.length(); |
| return this; |
| } |
| |
| public BytesBuilder append(byte[] bytes) { |
| ensureCapacity(len + bytes.length); |
| System.arraycopy(bytes, 0, ba, len, bytes.length); |
| len += bytes.length; |
| return this; |
| } |
| |
| /** |
| * Append a single byte. |
| * |
| * @param b take the lower 8 bits and appends it. |
| * @return self |
| */ |
| public BytesBuilder append(int b) { |
| ensureCapacity(len + 1); |
| ba[len] = (byte) b; |
| len += 1; |
| return this; |
| } |
| |
| /** |
| * Append a section of bytes from array |
| * |
| * @param bytes - bytes to be appended |
| * @param offset - start of bytes to be appended |
| * @param length - how many bytes from 'offset' to be appended |
| * @return self |
| */ |
| public BytesBuilder append(byte[] bytes, int offset, int length) { |
| ensureCapacity(len + length); |
| System.arraycopy(bytes, offset, ba, len, length); |
| len += length; |
| return this; |
| } |
| |
| /** |
| * Append a sequence of bytes from an InputStream |
| * |
| * @param in data source to append from |
| * @param length number of bytes to read from data source |
| * @return self |
| */ |
| public BytesBuilder append(InputStream in, int length) throws IOException { |
| ensureCapacity(len + length); |
| new DataInputStream(in).readFully(ba, len, length); |
| len += length; |
| return this; |
| } |
| |
| /** |
| * Append data from a ByteBuffer |
| * |
| * @param bb data is read from the ByteBuffer in such a way that its position is not changed. |
| * @return self |
| */ |
| public BytesBuilder append(ByteBuffer bb) { |
| int length = bb.remaining(); |
| ensureCapacity(len + length); |
| bb.duplicate().get(ba, len, length); |
| len += length; |
| return this; |
| } |
| |
| /** |
| * Sets the point at which appending will start. This method can shrink or grow the ByteBuilder |
| * from its current state. If it grows it will zero pad. |
| */ |
| public void setLength(int newLen) { |
| Preconditions.checkArgument(newLen >= 0, "Negative length passed : " + newLen); |
| if (newLen > ba.length) { |
| ba = Arrays.copyOf(ba, newLen); |
| } |
| |
| if (newLen > len) { |
| Arrays.fill(ba, len, newLen, (byte) 0); |
| } |
| |
| len = newLen; |
| } |
| |
| public int getLength() { |
| return len; |
| } |
| |
| public Bytes toBytes() { |
| return Bytes.of(ba, 0, len); |
| } |
| } |
| |
| /** |
| * Provides an efficient and reusable way to build immutable Bytes objects. |
| */ |
| public static BytesBuilder builder() { |
| return new BytesBuilder(); |
| } |
| |
| /** |
| * @param initialCapacity The initial size of the byte builders internal array. |
| */ |
| public static BytesBuilder builder(int initialCapacity) { |
| return new BytesBuilder(initialCapacity); |
| } |
| |
| /** |
| * Copy entire Bytes object to specific byte array. Uses the specified offset in the dest byte |
| * array to start the copy. |
| * |
| * @param dest destination array |
| * @param destPos starting position in the destination data. |
| * @exception IndexOutOfBoundsException if copying would cause access of data outside array |
| * bounds. |
| * @exception NullPointerException if either <code>src</code> or <code>dest</code> is |
| * <code>null</code>. |
| * @since 1.1.0 |
| */ |
| public void copyTo(byte[] dest, int destPos) { |
| arraycopy(0, dest, destPos, this.length); |
| } |
| |
| /** |
| * Copy a subsequence of Bytes to specific byte array. Uses the specified offset in the dest byte |
| * array to start the copy. |
| * |
| * @param start index of subsequence start (inclusive) |
| * @param end index of subsequence end (exclusive) |
| * @param dest destination array |
| * @param destPos starting position in the destination data. |
| * @exception IndexOutOfBoundsException if copying would cause access of data outside array |
| * bounds. |
| * @exception NullPointerException if either <code>src</code> or <code>dest</code> is |
| * <code>null</code>. |
| * @since 1.1.0 |
| */ |
| public void copyTo(int start, int end, byte[] dest, int destPos) { |
| // this.subSequence(start, end).copyTo(dest, destPos) would allocate another Bytes object |
| arraycopy(start, dest, destPos, end - start); |
| } |
| |
| private void arraycopy(int start, byte[] dest, int destPos, int length) { |
| // since dest is byte[], we can't get the ArrayStoreException |
| System.arraycopy(this.data, start + this.offset, dest, destPos, length); |
| } |
| |
| } |