1/* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17package com.android.tools.layoutlib.java; 18 19import java.nio.CharBuffer; 20import java.nio.charset.Charset; 21 22/** 23 * Defines the same class as the java.nio.charset.Charsets which was added in 24 * Dalvik VM. This hack, provides a replacement for that class which can't be 25 * loaded in the standard JVM since it's in the java package and standard JVM 26 * doesn't have it. An implementation of the native methods in the original 27 * class has been added. 28 * <p/> 29 * Extracted from API level 18, file: 30 * platform/libcore/luni/src/main/java/java/nio/charset/Charsets 31 */ 32public final class Charsets { 33 /** 34 * A cheap and type-safe constant for the ISO-8859-1 Charset. 35 */ 36 public static final Charset ISO_8859_1 = Charset.forName("ISO-8859-1"); 37 38 /** 39 * A cheap and type-safe constant for the US-ASCII Charset. 40 */ 41 public static final Charset US_ASCII = Charset.forName("US-ASCII"); 42 43 /** 44 * A cheap and type-safe constant for the UTF-8 Charset. 45 */ 46 public static final Charset UTF_8 = Charset.forName("UTF-8"); 47 48 /** 49 * Returns a new byte array containing the bytes corresponding to the given characters, 50 * encoded in US-ASCII. Unrepresentable characters are replaced by (byte) '?'. 51 */ 52 public static byte[] toAsciiBytes(char[] chars, int offset, int length) { 53 CharBuffer cb = CharBuffer.allocate(length); 54 cb.put(chars, offset, length); 55 return US_ASCII.encode(cb).array(); 56 } 57 58 /** 59 * Returns a new byte array containing the bytes corresponding to the given characters, 60 * encoded in ISO-8859-1. Unrepresentable characters are replaced by (byte) '?'. 61 */ 62 public static byte[] toIsoLatin1Bytes(char[] chars, int offset, int length) { 63 CharBuffer cb = CharBuffer.allocate(length); 64 cb.put(chars, offset, length); 65 return ISO_8859_1.encode(cb).array(); 66 } 67 68 /** 69 * Returns a new byte array containing the bytes corresponding to the given characters, 70 * encoded in UTF-8. All characters are representable in UTF-8. 71 */ 72 public static byte[] toUtf8Bytes(char[] chars, int offset, int length) { 73 CharBuffer cb = CharBuffer.allocate(length); 74 cb.put(chars, offset, length); 75 return UTF_8.encode(cb).array(); 76 } 77 78 /** 79 * Returns a new byte array containing the bytes corresponding to the given characters, 80 * encoded in UTF-16BE. All characters are representable in UTF-16BE. 81 */ 82 public static byte[] toBigEndianUtf16Bytes(char[] chars, int offset, int length) { 83 byte[] result = new byte[length * 2]; 84 int end = offset + length; 85 int resultIndex = 0; 86 for (int i = offset; i < end; ++i) { 87 char ch = chars[i]; 88 result[resultIndex++] = (byte) (ch >> 8); 89 result[resultIndex++] = (byte) ch; 90 } 91 return result; 92 } 93 94 /** 95 * Decodes the given US-ASCII bytes into the given char[]. Equivalent to but faster than: 96 * 97 * for (int i = 0; i < count; ++i) { 98 * char ch = (char) (data[start++] & 0xff); 99 * value[i] = (ch <= 0x7f) ? ch : REPLACEMENT_CHAR; 100 * } 101 */ 102 public static void asciiBytesToChars(byte[] bytes, int offset, int length, char[] chars) { 103 if (bytes == null || chars == null) { 104 return; 105 } 106 final char REPLACEMENT_CHAR = (char)0xffd; 107 int start = offset; 108 for (int i = 0; i < length; ++i) { 109 char ch = (char) (bytes[start++] & 0xff); 110 chars[i] = (ch <= 0x7f) ? ch : REPLACEMENT_CHAR; 111 } 112 } 113 114 /** 115 * Decodes the given ISO-8859-1 bytes into the given char[]. Equivalent to but faster than: 116 * 117 * for (int i = 0; i < count; ++i) { 118 * value[i] = (char) (data[start++] & 0xff); 119 * } 120 */ 121 public static void isoLatin1BytesToChars(byte[] bytes, int offset, int length, char[] chars) { 122 if (bytes == null || chars == null) { 123 return; 124 } 125 int start = offset; 126 for (int i = 0; i < length; ++i) { 127 chars[i] = (char) (bytes[start++] & 0xff); 128 } 129 } 130 131 private Charsets() { 132 } 133} 134