1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 18 package java.io; 19 20 /** 21 * A specialized {@link InputStream} that reads bytes from a {@code String} in 22 * a sequential manner. 23 * 24 * @deprecated Use {@link StringReader} 25 */ 26 @Deprecated 27 public class StringBufferInputStream extends InputStream { 28 /** 29 * The source string containing the data to read. 30 */ 31 protected String buffer; 32 33 /** 34 * The total number of characters in the source string. 35 */ 36 protected int count; 37 38 /** 39 * The current position within the source string. 40 */ 41 protected int pos; 42 43 /** 44 * Construct a new {@code StringBufferInputStream} with {@code str} as 45 * source. The size of the stream is set to the {@code length()} of the 46 * string. 47 * 48 * @param str 49 * the source string for this stream. 50 * @throws NullPointerException 51 * if {@code str} is {@code null}. 52 */ 53 public StringBufferInputStream(String str) { 54 if (str == null) { 55 throw new NullPointerException(); 56 } 57 buffer = str; 58 count = str.length(); 59 } 60 61 @Override 62 public synchronized int available() { 63 return count - pos; 64 } 65 66 /** 67 * Reads a single byte from the source string and returns it as an integer 68 * in the range from 0 to 255. Returns -1 if the end of the source string 69 * has been reached. 70 * 71 * @return the byte read or -1 if the end of the source string has been 72 * reached. 73 */ 74 @Override 75 public synchronized int read() { 76 return pos < count ? buffer.charAt(pos++) & 0xFF : -1; 77 } 78 79 /** 80 * Reads at most {@code length} bytes from the source string and stores them 81 * in the byte array {@code b} starting at {@code offset}. 82 * 83 * @param buffer 84 * the byte array in which to store the bytes read. 85 * @param offset 86 * the initial position in {@code b} to store the bytes read from 87 * this stream. 88 * @param length 89 * the maximum number of bytes to store in {@code b}. 90 * @return the number of bytes actually read or -1 if the end of the source 91 * string has been reached. 92 * @throws IndexOutOfBoundsException 93 * if {@code offset < 0} or {@code length < 0}, or if 94 * {@code offset + length} is greater than the length of 95 * {@code b}. 96 * @throws NullPointerException 97 * if {@code b} is {@code null}. 98 */ 99 @Override 100 public synchronized int read(byte[] buffer, int offset, int length) { 101 // BEGIN android-note 102 // changed array notation to be consistent with the rest of harmony 103 // END android-note 104 // According to 22.7.6 should return -1 before checking other 105 // parameters. 106 if (pos >= count) { 107 return -1; 108 } 109 if (buffer == null) { 110 throw new NullPointerException("buffer == null"); 111 } 112 // avoid int overflow 113 if (offset < 0 || offset > buffer.length) { 114 throw new ArrayIndexOutOfBoundsException("Offset out of bounds: " + offset); 115 } 116 if (length < 0 || length > buffer.length - offset) { 117 throw new ArrayIndexOutOfBoundsException("Length out of bounds: " + length); 118 } 119 120 if (length == 0) { 121 return 0; 122 } 123 124 int copylen = count - pos < length ? count - pos : length; 125 for (int i = 0; i < copylen; i++) { 126 buffer[offset + i] = (byte) this.buffer.charAt(pos + i); 127 } 128 pos += copylen; 129 return copylen; 130 } 131 132 /** 133 * Resets this stream to the beginning of the source string. 134 */ 135 @Override 136 public synchronized void reset() { 137 pos = 0; 138 } 139 140 /** 141 * Skips {@code n} characters in the source string. It does nothing and 142 * returns 0 if {@code n} is negative. Less than {@code n} characters are 143 * skipped if the end of the source string is reached before the operation 144 * completes. 145 * 146 * @param n 147 * the number of characters to skip. 148 * @return the number of characters actually skipped. 149 */ 150 @Override 151 public synchronized long skip(long n) { 152 if (n <= 0) { 153 return 0; 154 } 155 156 int numskipped; 157 if (this.count - pos < n) { 158 numskipped = this.count - pos; 159 pos = this.count; 160 } else { 161 numskipped = (int) n; 162 pos += n; 163 } 164 return numskipped; 165 } 166 } 167
