1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/emul/mini/src/main/java/java/io/ByteArrayInputStream.java Wed Jan 23 20:39:23 2013 +0100
1.3 @@ -0,0 +1,283 @@
1.4 +/*
1.5 + * Copyright (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved.
1.6 + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
1.7 + *
1.8 + * This code is free software; you can redistribute it and/or modify it
1.9 + * under the terms of the GNU General Public License version 2 only, as
1.10 + * published by the Free Software Foundation. Oracle designates this
1.11 + * particular file as subject to the "Classpath" exception as provided
1.12 + * by Oracle in the LICENSE file that accompanied this code.
1.13 + *
1.14 + * This code is distributed in the hope that it will be useful, but WITHOUT
1.15 + * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
1.16 + * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
1.17 + * version 2 for more details (a copy is included in the LICENSE file that
1.18 + * accompanied this code).
1.19 + *
1.20 + * You should have received a copy of the GNU General Public License version
1.21 + * 2 along with this work; if not, write to the Free Software Foundation,
1.22 + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
1.23 + *
1.24 + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
1.25 + * or visit www.oracle.com if you need additional information or have any
1.26 + * questions.
1.27 + */
1.28 +
1.29 +package java.io;
1.30 +
1.31 +/**
1.32 + * A <code>ByteArrayInputStream</code> contains
1.33 + * an internal buffer that contains bytes that
1.34 + * may be read from the stream. An internal
1.35 + * counter keeps track of the next byte to
1.36 + * be supplied by the <code>read</code> method.
1.37 + * <p>
1.38 + * Closing a <tt>ByteArrayInputStream</tt> has no effect. The methods in
1.39 + * this class can be called after the stream has been closed without
1.40 + * generating an <tt>IOException</tt>.
1.41 + *
1.42 + * @author Arthur van Hoff
1.43 + * @see java.io.StringBufferInputStream
1.44 + * @since JDK1.0
1.45 + */
1.46 +public
1.47 +class ByteArrayInputStream extends InputStream {
1.48 +
1.49 + /**
1.50 + * An array of bytes that was provided
1.51 + * by the creator of the stream. Elements <code>buf[0]</code>
1.52 + * through <code>buf[count-1]</code> are the
1.53 + * only bytes that can ever be read from the
1.54 + * stream; element <code>buf[pos]</code> is
1.55 + * the next byte to be read.
1.56 + */
1.57 + protected byte buf[];
1.58 +
1.59 + /**
1.60 + * The index of the next character to read from the input stream buffer.
1.61 + * This value should always be nonnegative
1.62 + * and not larger than the value of <code>count</code>.
1.63 + * The next byte to be read from the input stream buffer
1.64 + * will be <code>buf[pos]</code>.
1.65 + */
1.66 + protected int pos;
1.67 +
1.68 + /**
1.69 + * The currently marked position in the stream.
1.70 + * ByteArrayInputStream objects are marked at position zero by
1.71 + * default when constructed. They may be marked at another
1.72 + * position within the buffer by the <code>mark()</code> method.
1.73 + * The current buffer position is set to this point by the
1.74 + * <code>reset()</code> method.
1.75 + * <p>
1.76 + * If no mark has been set, then the value of mark is the offset
1.77 + * passed to the constructor (or 0 if the offset was not supplied).
1.78 + *
1.79 + * @since JDK1.1
1.80 + */
1.81 + protected int mark = 0;
1.82 +
1.83 + /**
1.84 + * The index one greater than the last valid character in the input
1.85 + * stream buffer.
1.86 + * This value should always be nonnegative
1.87 + * and not larger than the length of <code>buf</code>.
1.88 + * It is one greater than the position of
1.89 + * the last byte within <code>buf</code> that
1.90 + * can ever be read from the input stream buffer.
1.91 + */
1.92 + protected int count;
1.93 +
1.94 + /**
1.95 + * Creates a <code>ByteArrayInputStream</code>
1.96 + * so that it uses <code>buf</code> as its
1.97 + * buffer array.
1.98 + * The buffer array is not copied.
1.99 + * The initial value of <code>pos</code>
1.100 + * is <code>0</code> and the initial value
1.101 + * of <code>count</code> is the length of
1.102 + * <code>buf</code>.
1.103 + *
1.104 + * @param buf the input buffer.
1.105 + */
1.106 + public ByteArrayInputStream(byte buf[]) {
1.107 + this.buf = buf;
1.108 + this.pos = 0;
1.109 + this.count = buf.length;
1.110 + }
1.111 +
1.112 + /**
1.113 + * Creates <code>ByteArrayInputStream</code>
1.114 + * that uses <code>buf</code> as its
1.115 + * buffer array. The initial value of <code>pos</code>
1.116 + * is <code>offset</code> and the initial value
1.117 + * of <code>count</code> is the minimum of <code>offset+length</code>
1.118 + * and <code>buf.length</code>.
1.119 + * The buffer array is not copied. The buffer's mark is
1.120 + * set to the specified offset.
1.121 + *
1.122 + * @param buf the input buffer.
1.123 + * @param offset the offset in the buffer of the first byte to read.
1.124 + * @param length the maximum number of bytes to read from the buffer.
1.125 + */
1.126 + public ByteArrayInputStream(byte buf[], int offset, int length) {
1.127 + this.buf = buf;
1.128 + this.pos = offset;
1.129 + this.count = Math.min(offset + length, buf.length);
1.130 + this.mark = offset;
1.131 + }
1.132 +
1.133 + /**
1.134 + * Reads the next byte of data from this input stream. The value
1.135 + * byte is returned as an <code>int</code> in the range
1.136 + * <code>0</code> to <code>255</code>. If no byte is available
1.137 + * because the end of the stream has been reached, the value
1.138 + * <code>-1</code> is returned.
1.139 + * <p>
1.140 + * This <code>read</code> method
1.141 + * cannot block.
1.142 + *
1.143 + * @return the next byte of data, or <code>-1</code> if the end of the
1.144 + * stream has been reached.
1.145 + */
1.146 + public synchronized int read() {
1.147 + return (pos < count) ? (buf[pos++] & 0xff) : -1;
1.148 + }
1.149 +
1.150 + /**
1.151 + * Reads up to <code>len</code> bytes of data into an array of bytes
1.152 + * from this input stream.
1.153 + * If <code>pos</code> equals <code>count</code>,
1.154 + * then <code>-1</code> is returned to indicate
1.155 + * end of file. Otherwise, the number <code>k</code>
1.156 + * of bytes read is equal to the smaller of
1.157 + * <code>len</code> and <code>count-pos</code>.
1.158 + * If <code>k</code> is positive, then bytes
1.159 + * <code>buf[pos]</code> through <code>buf[pos+k-1]</code>
1.160 + * are copied into <code>b[off]</code> through
1.161 + * <code>b[off+k-1]</code> in the manner performed
1.162 + * by <code>System.arraycopy</code>. The
1.163 + * value <code>k</code> is added into <code>pos</code>
1.164 + * and <code>k</code> is returned.
1.165 + * <p>
1.166 + * This <code>read</code> method cannot block.
1.167 + *
1.168 + * @param b the buffer into which the data is read.
1.169 + * @param off the start offset in the destination array <code>b</code>
1.170 + * @param len the maximum number of bytes read.
1.171 + * @return the total number of bytes read into the buffer, or
1.172 + * <code>-1</code> if there is no more data because the end of
1.173 + * the stream has been reached.
1.174 + * @exception NullPointerException If <code>b</code> is <code>null</code>.
1.175 + * @exception IndexOutOfBoundsException If <code>off</code> is negative,
1.176 + * <code>len</code> is negative, or <code>len</code> is greater than
1.177 + * <code>b.length - off</code>
1.178 + */
1.179 + public synchronized int read(byte b[], int off, int len) {
1.180 + if (b == null) {
1.181 + throw new NullPointerException();
1.182 + } else if (off < 0 || len < 0 || len > b.length - off) {
1.183 + throw new IndexOutOfBoundsException();
1.184 + }
1.185 +
1.186 + if (pos >= count) {
1.187 + return -1;
1.188 + }
1.189 +
1.190 + int avail = count - pos;
1.191 + if (len > avail) {
1.192 + len = avail;
1.193 + }
1.194 + if (len <= 0) {
1.195 + return 0;
1.196 + }
1.197 + PushbackInputStream.arraycopy(buf, pos, b, off, len);
1.198 + pos += len;
1.199 + return len;
1.200 + }
1.201 +
1.202 + /**
1.203 + * Skips <code>n</code> bytes of input from this input stream. Fewer
1.204 + * bytes might be skipped if the end of the input stream is reached.
1.205 + * The actual number <code>k</code>
1.206 + * of bytes to be skipped is equal to the smaller
1.207 + * of <code>n</code> and <code>count-pos</code>.
1.208 + * The value <code>k</code> is added into <code>pos</code>
1.209 + * and <code>k</code> is returned.
1.210 + *
1.211 + * @param n the number of bytes to be skipped.
1.212 + * @return the actual number of bytes skipped.
1.213 + */
1.214 + public synchronized long skip(long n) {
1.215 + long k = count - pos;
1.216 + if (n < k) {
1.217 + k = n < 0 ? 0 : n;
1.218 + }
1.219 +
1.220 + pos += k;
1.221 + return k;
1.222 + }
1.223 +
1.224 + /**
1.225 + * Returns the number of remaining bytes that can be read (or skipped over)
1.226 + * from this input stream.
1.227 + * <p>
1.228 + * The value returned is <code>count - pos</code>,
1.229 + * which is the number of bytes remaining to be read from the input buffer.
1.230 + *
1.231 + * @return the number of remaining bytes that can be read (or skipped
1.232 + * over) from this input stream without blocking.
1.233 + */
1.234 + public synchronized int available() {
1.235 + return count - pos;
1.236 + }
1.237 +
1.238 + /**
1.239 + * Tests if this <code>InputStream</code> supports mark/reset. The
1.240 + * <code>markSupported</code> method of <code>ByteArrayInputStream</code>
1.241 + * always returns <code>true</code>.
1.242 + *
1.243 + * @since JDK1.1
1.244 + */
1.245 + public boolean markSupported() {
1.246 + return true;
1.247 + }
1.248 +
1.249 + /**
1.250 + * Set the current marked position in the stream.
1.251 + * ByteArrayInputStream objects are marked at position zero by
1.252 + * default when constructed. They may be marked at another
1.253 + * position within the buffer by this method.
1.254 + * <p>
1.255 + * If no mark has been set, then the value of the mark is the
1.256 + * offset passed to the constructor (or 0 if the offset was not
1.257 + * supplied).
1.258 + *
1.259 + * <p> Note: The <code>readAheadLimit</code> for this class
1.260 + * has no meaning.
1.261 + *
1.262 + * @since JDK1.1
1.263 + */
1.264 + public void mark(int readAheadLimit) {
1.265 + mark = pos;
1.266 + }
1.267 +
1.268 + /**
1.269 + * Resets the buffer to the marked position. The marked position
1.270 + * is 0 unless another position was marked or an offset was specified
1.271 + * in the constructor.
1.272 + */
1.273 + public synchronized void reset() {
1.274 + pos = mark;
1.275 + }
1.276 +
1.277 + /**
1.278 + * Closing a <tt>ByteArrayInputStream</tt> has no effect. The methods in
1.279 + * this class can be called after the stream has been closed without
1.280 + * generating an <tt>IOException</tt>.
1.281 + * <p>
1.282 + */
1.283 + public void close() throws IOException {
1.284 + }
1.285 +
1.286 +}