| /* |
| * 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.lucene.util; |
| |
| /* |
| * Some of this code came from the excellent Unicode |
| * conversion examples from: |
| * |
| * http://www.unicode.org/Public/PROGRAMS/CVTUTF |
| * |
| * Full Copyright for that code follows: |
| */ |
| |
| /* |
| * Copyright 2001-2004 Unicode, Inc. |
| * |
| * Disclaimer |
| * |
| * This source code is provided as is by Unicode, Inc. No claims are |
| * made as to fitness for any particular purpose. No warranties of any |
| * kind are expressed or implied. The recipient agrees to determine |
| * applicability of information provided. If this file has been |
| * purchased on magnetic or optical media from Unicode, Inc., the |
| * sole remedy for any claim will be exchange of defective media |
| * within 90 days of receipt. |
| * |
| * Limitations on Rights to Redistribute This Code |
| * |
| * Unicode, Inc. hereby grants the right to freely use the information |
| * supplied in this file in the creation of products supporting the |
| * Unicode Standard, and to make copies of this file in any form |
| * for internal or external distribution as long as this notice |
| * remains attached. |
| */ |
| |
| /* |
| * Additional code came from the IBM ICU library. |
| * |
| * http://www.icu-project.org |
| * |
| * Full Copyright for that code follows. |
| */ |
| |
| /* |
| * Copyright (C) 1999-2010, International Business Machines |
| * Corporation and others. All Rights Reserved. |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, and/or sell copies of the |
| * Software, and to permit persons to whom the Software is furnished to do so, |
| * provided that the above copyright notice(s) and this permission notice appear |
| * in all copies of the Software and that both the above copyright notice(s) and |
| * this permission notice appear in supporting documentation. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. |
| * IN NO EVENT SHALL THE COPYRIGHT HOLDER OR HOLDERS INCLUDED IN THIS NOTICE BE |
| * LIABLE FOR ANY CLAIM, OR ANY SPECIAL INDIRECT OR CONSEQUENTIAL DAMAGES, OR |
| * ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER |
| * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT |
| * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. |
| * |
| * Except as contained in this notice, the name of a copyright holder shall not |
| * be used in advertising or otherwise to promote the sale, use or other |
| * dealings in this Software without prior written authorization of the |
| * copyright holder. |
| */ |
| |
| import java.util.Arrays; |
| |
| /** |
| * Class to encode java's UTF16 char[] into UTF8 byte[] without always allocating a new byte[] as |
| * String.getBytes(StandardCharsets.UTF_8) does. |
| * |
| * @lucene.internal |
| */ |
| public final class UnicodeUtil { |
| |
| /** |
| * A binary term consisting of a number of 0xff bytes, likely to be bigger than other terms (e.g. |
| * collation keys) one would normally encounter, and definitely bigger than any UTF-8 terms. |
| * |
| * <p>WARNING: This is not a valid UTF8 Term |
| */ |
| public static final BytesRef BIG_TERM = |
| new BytesRef( |
| new byte[] { |
| -1, -1, -1, -1, -1, -1, -1, -1, -1, -1 |
| }); // TODO this is unrelated here find a better place for it |
| |
| private UnicodeUtil() {} // no instance |
| |
| public static final int UNI_SUR_HIGH_START = 0xD800; |
| public static final int UNI_SUR_HIGH_END = 0xDBFF; |
| public static final int UNI_SUR_LOW_START = 0xDC00; |
| public static final int UNI_SUR_LOW_END = 0xDFFF; |
| public static final int UNI_REPLACEMENT_CHAR = 0xFFFD; |
| |
| private static final long UNI_MAX_BMP = 0x0000FFFF; |
| |
| private static final long HALF_SHIFT = 10; |
| private static final long HALF_MASK = 0x3FFL; |
| |
| private static final int SURROGATE_OFFSET = |
| Character.MIN_SUPPLEMENTARY_CODE_POINT |
| - (UNI_SUR_HIGH_START << HALF_SHIFT) |
| - UNI_SUR_LOW_START; |
| |
| /** Maximum number of UTF8 bytes per UTF16 character. */ |
| public static final int MAX_UTF8_BYTES_PER_CHAR = 3; |
| |
| /** |
| * Encode characters from a char[] source, starting at offset for length chars. It is the |
| * responsibility of the caller to make sure that the destination array is large enough. |
| */ |
| public static int UTF16toUTF8( |
| final char[] source, final int offset, final int length, byte[] out) { |
| |
| int upto = 0; |
| int i = offset; |
| final int end = offset + length; |
| |
| while (i < end) { |
| |
| final int code = (int) source[i++]; |
| |
| if (code < 0x80) out[upto++] = (byte) code; |
| else if (code < 0x800) { |
| out[upto++] = (byte) (0xC0 | (code >> 6)); |
| out[upto++] = (byte) (0x80 | (code & 0x3F)); |
| } else if (code < 0xD800 || code > 0xDFFF) { |
| out[upto++] = (byte) (0xE0 | (code >> 12)); |
| out[upto++] = (byte) (0x80 | ((code >> 6) & 0x3F)); |
| out[upto++] = (byte) (0x80 | (code & 0x3F)); |
| } else { |
| // surrogate pair |
| // confirm valid high surrogate |
| if (code < 0xDC00 && i < end) { |
| int utf32 = (int) source[i]; |
| // confirm valid low surrogate and write pair |
| if (utf32 >= 0xDC00 && utf32 <= 0xDFFF) { |
| utf32 = (code << 10) + utf32 + SURROGATE_OFFSET; |
| i++; |
| out[upto++] = (byte) (0xF0 | (utf32 >> 18)); |
| out[upto++] = (byte) (0x80 | ((utf32 >> 12) & 0x3F)); |
| out[upto++] = (byte) (0x80 | ((utf32 >> 6) & 0x3F)); |
| out[upto++] = (byte) (0x80 | (utf32 & 0x3F)); |
| continue; |
| } |
| } |
| // replace unpaired surrogate or out-of-order low surrogate |
| // with substitution character |
| out[upto++] = (byte) 0xEF; |
| out[upto++] = (byte) 0xBF; |
| out[upto++] = (byte) 0xBD; |
| } |
| } |
| // assert matches(source, offset, length, out, upto); |
| return upto; |
| } |
| |
| /** |
| * Encode characters from this String, starting at offset for length characters. It is the |
| * responsibility of the caller to make sure that the destination array is large enough. |
| */ |
| public static int UTF16toUTF8( |
| final CharSequence s, final int offset, final int length, byte[] out) { |
| return UTF16toUTF8(s, offset, length, out, 0); |
| } |
| |
| /** |
| * Encode characters from this String, starting at offset for length characters. Output to the |
| * destination array will begin at {@code outOffset}. It is the responsibility of the caller to |
| * make sure that the destination array is large enough. |
| * |
| * <p>note this method returns the final output offset (outOffset + number of bytes written) |
| */ |
| public static int UTF16toUTF8( |
| final CharSequence s, final int offset, final int length, byte[] out, int outOffset) { |
| final int end = offset + length; |
| |
| int upto = outOffset; |
| for (int i = offset; i < end; i++) { |
| final int code = (int) s.charAt(i); |
| |
| if (code < 0x80) out[upto++] = (byte) code; |
| else if (code < 0x800) { |
| out[upto++] = (byte) (0xC0 | (code >> 6)); |
| out[upto++] = (byte) (0x80 | (code & 0x3F)); |
| } else if (code < 0xD800 || code > 0xDFFF) { |
| out[upto++] = (byte) (0xE0 | (code >> 12)); |
| out[upto++] = (byte) (0x80 | ((code >> 6) & 0x3F)); |
| out[upto++] = (byte) (0x80 | (code & 0x3F)); |
| } else { |
| // surrogate pair |
| // confirm valid high surrogate |
| if (code < 0xDC00 && (i < end - 1)) { |
| int utf32 = (int) s.charAt(i + 1); |
| // confirm valid low surrogate and write pair |
| if (utf32 >= 0xDC00 && utf32 <= 0xDFFF) { |
| utf32 = (code << 10) + utf32 + SURROGATE_OFFSET; |
| i++; |
| out[upto++] = (byte) (0xF0 | (utf32 >> 18)); |
| out[upto++] = (byte) (0x80 | ((utf32 >> 12) & 0x3F)); |
| out[upto++] = (byte) (0x80 | ((utf32 >> 6) & 0x3F)); |
| out[upto++] = (byte) (0x80 | (utf32 & 0x3F)); |
| continue; |
| } |
| } |
| // replace unpaired surrogate or out-of-order low surrogate |
| // with substitution character |
| out[upto++] = (byte) 0xEF; |
| out[upto++] = (byte) 0xBF; |
| out[upto++] = (byte) 0xBD; |
| } |
| } |
| // assert matches(s, offset, length, out, upto); |
| return upto; |
| } |
| |
| /** |
| * Calculates the number of UTF8 bytes necessary to write a UTF16 string. |
| * |
| * @return the number of bytes written |
| */ |
| public static int calcUTF16toUTF8Length(final CharSequence s, final int offset, final int len) { |
| final int end = offset + len; |
| |
| int res = 0; |
| for (int i = offset; i < end; i++) { |
| final int code = (int) s.charAt(i); |
| |
| if (code < 0x80) res++; |
| else if (code < 0x800) { |
| res += 2; |
| } else if (code < 0xD800 || code > 0xDFFF) { |
| res += 3; |
| } else { |
| // surrogate pair |
| // confirm valid high surrogate |
| if (code < 0xDC00 && (i < end - 1)) { |
| int utf32 = (int) s.charAt(i + 1); |
| // confirm valid low surrogate and write pair |
| if (utf32 >= 0xDC00 && utf32 <= 0xDFFF) { |
| i++; |
| res += 4; |
| continue; |
| } |
| } |
| res += 3; |
| } |
| } |
| |
| return res; |
| } |
| |
| // Only called from assert |
| /* |
| private static boolean matches(char[] source, int offset, int length, byte[] result, int upto) { |
| try { |
| String s1 = new String(source, offset, length); |
| String s2 = new String(result, 0, upto, StandardCharsets.UTF_8); |
| if (!s1.equals(s2)) { |
| //System.out.println("DIFF: s1 len=" + s1.length()); |
| //for(int i=0;i<s1.length();i++) |
| // System.out.println(" " + i + ": " + (int) s1.charAt(i)); |
| //System.out.println("s2 len=" + s2.length()); |
| //for(int i=0;i<s2.length();i++) |
| // System.out.println(" " + i + ": " + (int) s2.charAt(i)); |
| |
| // If the input string was invalid, then the |
| // difference is OK |
| if (!validUTF16String(s1)) |
| return true; |
| |
| return false; |
| } |
| return s1.equals(s2); |
| } catch (UnsupportedEncodingException uee) { |
| return false; |
| } |
| } |
| |
| // Only called from assert |
| private static boolean matches(String source, int offset, int length, byte[] result, int upto) { |
| try { |
| String s1 = source.substring(offset, offset+length); |
| String s2 = new String(result, 0, upto, StandardCharsets.UTF_8); |
| if (!s1.equals(s2)) { |
| // Allow a difference if s1 is not valid UTF-16 |
| |
| //System.out.println("DIFF: s1 len=" + s1.length()); |
| //for(int i=0;i<s1.length();i++) |
| // System.out.println(" " + i + ": " + (int) s1.charAt(i)); |
| //System.out.println(" s2 len=" + s2.length()); |
| //for(int i=0;i<s2.length();i++) |
| // System.out.println(" " + i + ": " + (int) s2.charAt(i)); |
| |
| // If the input string was invalid, then the |
| // difference is OK |
| if (!validUTF16String(s1)) |
| return true; |
| |
| return false; |
| } |
| return s1.equals(s2); |
| } catch (UnsupportedEncodingException uee) { |
| return false; |
| } |
| } |
| */ |
| public static boolean validUTF16String(CharSequence s) { |
| final int size = s.length(); |
| for (int i = 0; i < size; i++) { |
| char ch = s.charAt(i); |
| if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END) { |
| if (i < size - 1) { |
| i++; |
| char nextCH = s.charAt(i); |
| if (nextCH >= UNI_SUR_LOW_START && nextCH <= UNI_SUR_LOW_END) { |
| // Valid surrogate pair |
| } else |
| // Unmatched high surrogate |
| return false; |
| } else |
| // Unmatched high surrogate |
| return false; |
| } else if (ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END) |
| // Unmatched low surrogate |
| return false; |
| } |
| |
| return true; |
| } |
| |
| public static boolean validUTF16String(char[] s, int size) { |
| for (int i = 0; i < size; i++) { |
| char ch = s[i]; |
| if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END) { |
| if (i < size - 1) { |
| i++; |
| char nextCH = s[i]; |
| if (nextCH >= UNI_SUR_LOW_START && nextCH <= UNI_SUR_LOW_END) { |
| // Valid surrogate pair |
| } else { |
| return false; |
| } |
| } else { |
| return false; |
| } |
| } else if (ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END) |
| // Unmatched low surrogate |
| return false; |
| } |
| |
| return true; |
| } |
| |
| // Borrowed from Python's 3.1.2 sources, |
| // Objects/unicodeobject.c, and modified (see commented |
| // out section, and the -1s) to disallow the reserved for |
| // future (RFC 3629) 5/6 byte sequence characters, and |
| // invalid 0xFE and 0xFF bytes. |
| |
| /** |
| * Map UTF-8 encoded prefix byte to sequence length. -1 (0xFF) means illegal prefix. see RFC 2279 |
| * for details |
| */ |
| static final int[] utf8CodeLength; |
| |
| static { |
| final int v = Integer.MIN_VALUE; |
| |
| // Build the codes from a rectangular array, otherwise the formatter |
| // puts each value on a single line. Hard to fix in any other way. |
| utf8CodeLength = |
| Arrays.stream( |
| new int[][] { |
| {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, |
| {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, |
| {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, |
| {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, |
| {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, |
| {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, |
| {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, |
| {1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1}, |
| {v, v, v, v, v, v, v, v, v, v, v, v, v, v, v, v}, |
| {v, v, v, v, v, v, v, v, v, v, v, v, v, v, v, v}, |
| {v, v, v, v, v, v, v, v, v, v, v, v, v, v, v, v}, |
| {v, v, v, v, v, v, v, v, v, v, v, v, v, v, v, v}, |
| {2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2}, |
| {2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2}, |
| {3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3}, |
| {4, 4, 4, 4, 4, 4, 4, 4 /* , 5, 5, 5, 5, 6, 6, 0, 0 */} |
| }) |
| .flatMapToInt(Arrays::stream) |
| .toArray(); |
| } |
| |
| /** |
| * Returns the number of code points in this UTF8 sequence. |
| * |
| * <p>This method assumes valid UTF8 input. This method <strong>does not perform</strong> full |
| * UTF8 validation, it will check only the first byte of each codepoint (for multi-byte sequences |
| * any bytes after the head are skipped). |
| * |
| * @throws IllegalArgumentException If invalid codepoint header byte occurs or the content is |
| * prematurely truncated. |
| */ |
| public static int codePointCount(BytesRef utf8) { |
| int pos = utf8.offset; |
| final int limit = pos + utf8.length; |
| final byte[] bytes = utf8.bytes; |
| |
| int codePointCount = 0; |
| for (; pos < limit; codePointCount++) { |
| int v = bytes[pos] & 0xFF; |
| if (v < /* 0xxx xxxx */ 0x80) { |
| pos += 1; |
| continue; |
| } |
| if (v >= /* 110x xxxx */ 0xc0) { |
| if (v < /* 111x xxxx */ 0xe0) { |
| pos += 2; |
| continue; |
| } |
| if (v < /* 1111 xxxx */ 0xf0) { |
| pos += 3; |
| continue; |
| } |
| if (v < /* 1111 1xxx */ 0xf8) { |
| pos += 4; |
| continue; |
| } |
| // fallthrough, consider 5 and 6 byte sequences invalid. |
| } |
| |
| // Anything not covered above is invalid UTF8. |
| throw new IllegalArgumentException(); |
| } |
| |
| // Check if we didn't go over the limit on the last character. |
| if (pos > limit) throw new IllegalArgumentException(); |
| |
| return codePointCount; |
| } |
| |
| /** |
| * This method assumes valid UTF8 input. This method <strong>does not perform</strong> full UTF8 |
| * validation, it will check only the first byte of each codepoint (for multi-byte sequences any |
| * bytes after the head are skipped). It is the responsibility of the caller to make sure that the |
| * destination array is large enough. |
| * |
| * @throws IllegalArgumentException If invalid codepoint header byte occurs or the content is |
| * prematurely truncated. |
| */ |
| public static int UTF8toUTF32(final BytesRef utf8, final int[] ints) { |
| // TODO: ints must not be null, should be an assert |
| int utf32Count = 0; |
| int utf8Upto = utf8.offset; |
| final byte[] bytes = utf8.bytes; |
| final int utf8Limit = utf8.offset + utf8.length; |
| while (utf8Upto < utf8Limit) { |
| final int numBytes = utf8CodeLength[bytes[utf8Upto] & 0xFF]; |
| int v = 0; |
| switch (numBytes) { |
| case 1: |
| ints[utf32Count++] = bytes[utf8Upto++]; |
| continue; |
| case 2: |
| // 5 useful bits |
| v = bytes[utf8Upto++] & 31; |
| break; |
| case 3: |
| // 4 useful bits |
| v = bytes[utf8Upto++] & 15; |
| break; |
| case 4: |
| // 3 useful bits |
| v = bytes[utf8Upto++] & 7; |
| break; |
| default: |
| throw new IllegalArgumentException("invalid utf8"); |
| } |
| |
| // TODO: this may read past utf8's limit. |
| final int limit = utf8Upto + numBytes - 1; |
| while (utf8Upto < limit) { |
| v = v << 6 | bytes[utf8Upto++] & 63; |
| } |
| ints[utf32Count++] = v; |
| } |
| |
| return utf32Count; |
| } |
| |
| /** Shift value for lead surrogate to form a supplementary character. */ |
| private static final int LEAD_SURROGATE_SHIFT_ = 10; |
| /** Mask to retrieve the significant value from a trail surrogate. */ |
| private static final int TRAIL_SURROGATE_MASK_ = 0x3FF; |
| /** Trail surrogate minimum value */ |
| private static final int TRAIL_SURROGATE_MIN_VALUE = 0xDC00; |
| /** Lead surrogate minimum value */ |
| private static final int LEAD_SURROGATE_MIN_VALUE = 0xD800; |
| /** The minimum value for Supplementary code points */ |
| private static final int SUPPLEMENTARY_MIN_VALUE = 0x10000; |
| /** Value that all lead surrogate starts with */ |
| private static final int LEAD_SURROGATE_OFFSET_ = |
| LEAD_SURROGATE_MIN_VALUE - (SUPPLEMENTARY_MIN_VALUE >> LEAD_SURROGATE_SHIFT_); |
| |
| /** |
| * Cover JDK 1.5 API. Create a String from an array of codePoints. |
| * |
| * @param codePoints The code array |
| * @param offset The start of the text in the code point array |
| * @param count The number of code points |
| * @return a String representing the code points between offset and count |
| * @throws IllegalArgumentException If an invalid code point is encountered |
| * @throws IndexOutOfBoundsException If the offset or count are out of bounds. |
| */ |
| public static String newString(int[] codePoints, int offset, int count) { |
| if (count < 0) { |
| throw new IllegalArgumentException(); |
| } |
| char[] chars = new char[count]; |
| int w = 0; |
| for (int r = offset, e = offset + count; r < e; ++r) { |
| int cp = codePoints[r]; |
| if (cp < 0 || cp > 0x10ffff) { |
| throw new IllegalArgumentException(); |
| } |
| while (true) { |
| try { |
| if (cp < 0x010000) { |
| chars[w] = (char) cp; |
| w++; |
| } else { |
| chars[w] = (char) (LEAD_SURROGATE_OFFSET_ + (cp >> LEAD_SURROGATE_SHIFT_)); |
| chars[w + 1] = (char) (TRAIL_SURROGATE_MIN_VALUE + (cp & TRAIL_SURROGATE_MASK_)); |
| w += 2; |
| } |
| break; |
| } catch (IndexOutOfBoundsException ex) { |
| int newlen = (int) (Math.ceil((double) codePoints.length * (w + 2) / (r - offset + 1))); |
| char[] temp = new char[newlen]; |
| System.arraycopy(chars, 0, temp, 0, w); |
| chars = temp; |
| } |
| } |
| } |
| return new String(chars, 0, w); |
| } |
| |
| // for debugging |
| public static String toHexString(String s) { |
| StringBuilder sb = new StringBuilder(); |
| for (int i = 0; i < s.length(); i++) { |
| char ch = s.charAt(i); |
| if (i > 0) { |
| sb.append(' '); |
| } |
| if (ch < 128) { |
| sb.append(ch); |
| } else { |
| if (ch >= UNI_SUR_HIGH_START && ch <= UNI_SUR_HIGH_END) { |
| sb.append("H:"); |
| } else if (ch >= UNI_SUR_LOW_START && ch <= UNI_SUR_LOW_END) { |
| sb.append("L:"); |
| } else if (ch > UNI_SUR_LOW_END) { |
| if (ch == 0xffff) { |
| sb.append("F:"); |
| } else { |
| sb.append("E:"); |
| } |
| } |
| |
| sb.append("0x").append(Integer.toHexString(ch)); |
| } |
| } |
| return sb.toString(); |
| } |
| |
| /** |
| * Interprets the given byte array as UTF-8 and converts to UTF-16. It is the responsibility of |
| * the caller to make sure that the destination array is large enough. |
| * |
| * <p>NOTE: Full characters are read, even if this reads past the length passed (and can result in |
| * an ArrayOutOfBoundsException if invalid UTF-8 is passed). Explicit checks for valid UTF-8 are |
| * not performed. |
| */ |
| // TODO: broken if chars.offset != 0 |
| public static int UTF8toUTF16(byte[] utf8, int offset, int length, char[] out) { |
| int out_offset = 0; |
| final int limit = offset + length; |
| while (offset < limit) { |
| int b = utf8[offset++] & 0xff; |
| if (b < 0xc0) { |
| assert b < 0x80; |
| out[out_offset++] = (char) b; |
| } else if (b < 0xe0) { |
| out[out_offset++] = (char) (((b & 0x1f) << 6) + (utf8[offset++] & 0x3f)); |
| } else if (b < 0xf0) { |
| out[out_offset++] = |
| (char) (((b & 0xf) << 12) + ((utf8[offset] & 0x3f) << 6) + (utf8[offset + 1] & 0x3f)); |
| offset += 2; |
| } else { |
| assert b < 0xf8 : "b = 0x" + Integer.toHexString(b); |
| int ch = |
| ((b & 0x7) << 18) |
| + ((utf8[offset] & 0x3f) << 12) |
| + ((utf8[offset + 1] & 0x3f) << 6) |
| + (utf8[offset + 2] & 0x3f); |
| offset += 3; |
| if (ch < UNI_MAX_BMP) { |
| out[out_offset++] = (char) ch; |
| } else { |
| int chHalf = ch - 0x0010000; |
| out[out_offset++] = (char) ((chHalf >> 10) + 0xD800); |
| out[out_offset++] = (char) ((chHalf & HALF_MASK) + 0xDC00); |
| } |
| } |
| } |
| return out_offset; |
| } |
| |
| /** |
| * Returns the maximum number of utf8 bytes required to encode a utf16 (e.g., java char[], String) |
| */ |
| public static int maxUTF8Length(int utf16Length) { |
| return Math.multiplyExact(utf16Length, MAX_UTF8_BYTES_PER_CHAR); |
| } |
| |
| /** |
| * Utility method for {@link #UTF8toUTF16(byte[], int, int, char[])} |
| * |
| * @see #UTF8toUTF16(byte[], int, int, char[]) |
| */ |
| public static int UTF8toUTF16(BytesRef bytesRef, char[] chars) { |
| return UTF8toUTF16(bytesRef.bytes, bytesRef.offset, bytesRef.length, chars); |
| } |
| } |