Showing the changes to java/pkg/java/io/CharArrayWriter.java (1 of 18352 files). Show all
Unified · Split
| @@ -0,0 +1,280 @@ | |||
| 1 | /* | ||
| 2 | * Copyright (c) 1996, 2005, Oracle and/or its affiliates. All rights reserved. | ||
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | ||
| 4 | * | ||
| 5 | * This code is free software; you can redistribute it and/or modify it | ||
| 6 | * under the terms of the GNU General Public License version 2 only, as | ||
| 7 | * published by the Free Software Foundation. Oracle designates this | ||
| 8 | * particular file as subject to the "Classpath" exception as provided | ||
| 9 | * by Oracle in the LICENSE file that accompanied this code. | ||
| 10 | * | ||
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT | ||
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | ||
| 14 | * version 2 for more details (a copy is included in the LICENSE file that | ||
| 15 | * accompanied this code). | ||
| 16 | * | ||
| 17 | * You should have received a copy of the GNU General Public License version | ||
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, | ||
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | ||
| 20 | * | ||
| 21 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | ||
| 22 | * or visit www.oracle.com if you need additional information or have any | ||
| 23 | * questions. | ||
| 24 | */ | ||
| 25 | |||
| 26 | package java.io; | ||
| 27 | |||
| 28 | import java.util.Arrays; | ||
| 29 | |||
| 30 | /** | ||
| 31 | * This class implements a character buffer that can be used as an Writer. | ||
| 32 | * The buffer automatically grows when data is written to the stream. The data | ||
| 33 | * can be retrieved using toCharArray() and toString(). | ||
| 34 | * <P> | ||
| 35 | * Note: Invoking close() on this class has no effect, and methods | ||
| 36 | * of this class can be called after the stream has closed | ||
| 37 | * without generating an IOException. | ||
| 38 | * | ||
| 39 | * @author Herb Jellinek | ||
| 40 | * @since JDK1.1 | ||
| 41 | */ | ||
| 42 | public | ||
| 43 | class CharArrayWriter extends Writer { | ||
| 44 | /** | ||
| 45 | * The buffer where data is stored. | ||
| 46 | */ | ||
| 47 | protected char buf[]; | ||
| 48 | |||
| 49 | /** | ||
| 50 | * The number of chars in the buffer. | ||
| 51 | */ | ||
| 52 | protected int count; | ||
| 53 | |||
| 54 | /** | ||
| 55 | * Creates a new CharArrayWriter. | ||
| 56 | */ | ||
| 57 | public CharArrayWriter() { | ||
| 58 | this(32); | ||
| 59 | } | ||
| 60 | |||
| 61 | /** | ||
| 62 | * Creates a new CharArrayWriter with the specified initial size. | ||
| 63 | * | ||
| 64 | * @param initialSize an int specifying the initial buffer size. | ||
| 65 | * @exception IllegalArgumentException if initialSize is negative | ||
| 66 | */ | ||
| 67 | public CharArrayWriter(int initialSize) { | ||
| 68 | if (initialSize < 0) { | ||
| 69 | throw new IllegalArgumentException("Negative initial size: " | ||
| 70 | + initialSize); | ||
| 71 | } | ||
| 72 | buf = new char[initialSize]; | ||
| 73 | } | ||
| 74 | |||
| 75 | /** | ||
| 76 | * Writes a character to the buffer. | ||
| 77 | */ | ||
| 78 | public void write(int c) { | ||
| 79 | synchronized (lock) { | ||
| 80 | int newcount = count + 1; | ||
| 81 | if (newcount > buf.length) { | ||
| 82 | buf = Arrays.copyOf(buf, Math.max(buf.length << 1, newcount)); | ||
| 83 | } | ||
| 84 | buf[count] = (char)c; | ||
| 85 | count = newcount; | ||
| 86 | } | ||
| 87 | } | ||
| 88 | |||
| 89 | /** | ||
| 90 | * Writes characters to the buffer. | ||
| 91 | * @param c the data to be written | ||
| 92 | * @param off the start offset in the data | ||
| 93 | * @param len the number of chars that are written | ||
| 94 | */ | ||
| 95 | public void write(char c[], int off, int len) { | ||
| 96 | if ((off < 0) || (off > c.length) || (len < 0) || | ||
| 97 | ((off + len) > c.length) || ((off + len) < 0)) { | ||
| 98 | throw new IndexOutOfBoundsException(); | ||
| 99 | } else if (len == 0) { | ||
| 100 | return; | ||
| 101 | } | ||
| 102 | synchronized (lock) { | ||
| 103 | int newcount = count + len; | ||
| 104 | if (newcount > buf.length) { | ||
| 105 | buf = Arrays.copyOf(buf, Math.max(buf.length << 1, newcount)); | ||
| 106 | } | ||
| 107 | System.arraycopy(c, off, buf, count, len); | ||
| 108 | count = newcount; | ||
| 109 | } | ||
| 110 | } | ||
| 111 | |||
| 112 | /** | ||
| 113 | * Write a portion of a string to the buffer. | ||
| 114 | * @param str String to be written from | ||
| 115 | * @param off Offset from which to start reading characters | ||
| 116 | * @param len Number of characters to be written | ||
| 117 | */ | ||
| 118 | public void write(String str, int off, int len) { | ||
| 119 | synchronized (lock) { | ||
| 120 | int newcount = count + len; | ||
| 121 | if (newcount > buf.length) { | ||
| 122 | buf = Arrays.copyOf(buf, Math.max(buf.length << 1, newcount)); | ||
| 123 | } | ||
| 124 | str.getChars(off, off + len, buf, count); | ||
| 125 | count = newcount; | ||
| 126 | } | ||
| 127 | } | ||
| 128 | |||
| 129 | /** | ||
| 130 | * Writes the contents of the buffer to another character stream. | ||
| 131 | * | ||
| 132 | * @param out the output stream to write to | ||
| 133 | * @throws IOException If an I/O error occurs. | ||
| 134 | */ | ||
| 135 | public void writeTo(Writer out) throws IOException { | ||
| 136 | synchronized (lock) { | ||
| 137 | out.write(buf, 0, count); | ||
| 138 | } | ||
| 139 | } | ||
| 140 | |||
| 141 | /** | ||
| 142 | * Appends the specified character sequence to this writer. | ||
| 143 | * | ||
| 144 | * <p> An invocation of this method of the form <tt>out.append(csq)</tt> | ||
| 145 | * behaves in exactly the same way as the invocation | ||
| 146 | * | ||
| 147 | * <pre> | ||
| 148 | * out.write(csq.toString()) </pre> | ||
| 149 | * | ||
| 150 | * <p> Depending on the specification of <tt>toString</tt> for the | ||
| 151 | * character sequence <tt>csq</tt>, the entire sequence may not be | ||
| 152 | * appended. For instance, invoking the <tt>toString</tt> method of a | ||
| 153 | * character buffer will return a subsequence whose content depends upon | ||
| 154 | * the buffer's position and limit. | ||
| 155 | * | ||
| 156 | * @param csq | ||
| 157 | * The character sequence to append. If <tt>csq</tt> is | ||
| 158 | * <tt>null</tt>, then the four characters <tt>"null"</tt> are | ||
| 159 | * appended to this writer. | ||
| 160 | * | ||
| 161 | * @return This writer | ||
| 162 | * | ||
| 163 | * @since 1.5 | ||
| 164 | */ | ||
| 165 | public CharArrayWriter append(CharSequence csq) { | ||
| 166 | String s = (csq == null ? "null" : csq.toString()); | ||
| 167 | write(s, 0, s.length()); | ||
| 168 | return this; | ||
| 169 | } | ||
| 170 | |||
| 171 | /** | ||
| 172 | * Appends a subsequence of the specified character sequence to this writer. | ||
| 173 | * | ||
| 174 | * <p> An invocation of this method of the form <tt>out.append(csq, start, | ||
| 175 | * end)</tt> when <tt>csq</tt> is not <tt>null</tt>, behaves in | ||
| 176 | * exactly the same way as the invocation | ||
| 177 | * | ||
| 178 | * <pre> | ||
| 179 | * out.write(csq.subSequence(start, end).toString()) </pre> | ||
| 180 | * | ||
| 181 | * @param csq | ||
| 182 | * The character sequence from which a subsequence will be | ||
| 183 | * appended. If <tt>csq</tt> is <tt>null</tt>, then characters | ||
| 184 | * will be appended as if <tt>csq</tt> contained the four | ||
| 185 | * characters <tt>"null"</tt>. | ||
| 186 | * | ||
| 187 | * @param start | ||
| 188 | * The index of the first character in the subsequence | ||
| 189 | * | ||
| 190 | * @param end | ||
| 191 | * The index of the character following the last character in the | ||
| 192 | * subsequence | ||
| 193 | * | ||
| 194 | * @return This writer | ||
| 195 | * | ||
| 196 | * @throws IndexOutOfBoundsException | ||
| 197 | * If <tt>start</tt> or <tt>end</tt> are negative, <tt>start</tt> | ||
| 198 | * is greater than <tt>end</tt>, or <tt>end</tt> is greater than | ||
| 199 | * <tt>csq.length()</tt> | ||
| 200 | * | ||
| 201 | * @since 1.5 | ||
| 202 | */ | ||
| 203 | public CharArrayWriter append(CharSequence csq, int start, int end) { | ||
| 204 | String s = (csq == null ? "null" : csq).subSequence(start, end).toString(); | ||
| 205 | write(s, 0, s.length()); | ||
| 206 | return this; | ||
| 207 | } | ||
| 208 | |||
| 209 | /** | ||
| 210 | * Appends the specified character to this writer. | ||
| 211 | * | ||
| 212 | * <p> An invocation of this method of the form <tt>out.append(c)</tt> | ||
| 213 | * behaves in exactly the same way as the invocation | ||
| 214 | * | ||
| 215 | * <pre> | ||
| 216 | * out.write(c) </pre> | ||
| 217 | * | ||
| 218 | * @param c | ||
| 219 | * The 16-bit character to append | ||
| 220 | * | ||
| 221 | * @return This writer | ||
| 222 | * | ||
| 223 | * @since 1.5 | ||
| 224 | */ | ||
| 225 | public CharArrayWriter append(char c) { | ||
| 226 | write(c); | ||
| 227 | return this; | ||
| 228 | } | ||
| 229 | |||
| 230 | /** | ||
| 231 | * Resets the buffer so that you can use it again without | ||
| 232 | * throwing away the already allocated buffer. | ||
| 233 | */ | ||
| 234 | public void reset() { | ||
| 235 | count = 0; | ||
| 236 | } | ||
| 237 | |||
| 238 | /** | ||
| 239 | * Returns a copy of the input data. | ||
| 240 | * | ||
| 241 | * @return an array of chars copied from the input data. | ||
| 242 | */ | ||
| 243 | public char toCharArray()[] { | ||
| 244 | synchronized (lock) { | ||
| 245 | return Arrays.copyOf(buf, count); | ||
| 246 | } | ||
| 247 | } | ||
| 248 | |||
| 249 | /** | ||
| 250 | * Returns the current size of the buffer. | ||
| 251 | * | ||
| 252 | * @return an int representing the current size of the buffer. | ||
| 253 | */ | ||
| 254 | public int size() { | ||
| 255 | return count; | ||
| 256 | } | ||
| 257 | |||
| 258 | /** | ||
| 259 | * Converts input data to a string. | ||
| 260 | * @return the string. | ||
| 261 | */ | ||
| 262 | public String toString() { | ||
| 263 | synchronized (lock) { | ||
| 264 | return new String(buf, 0, count); | ||
| 265 | } | ||
| 266 | } | ||
| 267 | |||
| 268 | /** | ||
| 269 | * Flush the stream. | ||
| 270 | */ | ||
| 271 | public void flush() { } | ||
| 272 | |||
| 273 | /** | ||
| 274 | * Close the stream. This method does not release the buffer, since its | ||
| 275 | * contents might still be required. Note: Invoking this method in this class | ||
| 276 | * will have no effect. | ||
| 277 | */ | ||
| 278 | public void close() { } | ||
| 279 | |||
| 280 | } | ||