001: /*
002: * Copyright 1994-2004 Sun Microsystems, Inc. All Rights Reserved.
003: * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
004: *
005: * This code is free software; you can redistribute it and/or modify it
006: * under the terms of the GNU General Public License version 2 only, as
007: * published by the Free Software Foundation. Sun designates this
008: * particular file as subject to the "Classpath" exception as provided
009: * by Sun in the LICENSE file that accompanied this code.
010: *
011: * This code is distributed in the hope that it will be useful, but WITHOUT
012: * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
013: * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
014: * version 2 for more details (a copy is included in the LICENSE file that
015: * accompanied this code).
016: *
017: * You should have received a copy of the GNU General Public License version
018: * 2 along with this work; if not, write to the Free Software Foundation,
019: * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
020: *
021: * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
022: * CA 95054 USA or visit www.sun.com if you need additional information or
023: * have any questions.
024: */
025:
026: package java.io;
027:
028: /**
029: * This abstract class is the superclass of all classes representing
030: * an output stream of bytes. An output stream accepts output bytes
031: * and sends them to some sink.
032: * <p>
033: * Applications that need to define a subclass of
034: * <code>OutputStream</code> must always provide at least a method
035: * that writes one byte of output.
036: *
037: * @author Arthur van Hoff
038: * @version 1.36, 05/05/07
039: * @see java.io.BufferedOutputStream
040: * @see java.io.ByteArrayOutputStream
041: * @see java.io.DataOutputStream
042: * @see java.io.FilterOutputStream
043: * @see java.io.InputStream
044: * @see java.io.OutputStream#write(int)
045: * @since JDK1.0
046: */
047: public abstract class OutputStream implements Closeable, Flushable {
048: /**
049: * Writes the specified byte to this output stream. The general
050: * contract for <code>write</code> is that one byte is written
051: * to the output stream. The byte to be written is the eight
052: * low-order bits of the argument <code>b</code>. The 24
053: * high-order bits of <code>b</code> are ignored.
054: * <p>
055: * Subclasses of <code>OutputStream</code> must provide an
056: * implementation for this method.
057: *
058: * @param b the <code>byte</code>.
059: * @exception IOException if an I/O error occurs. In particular,
060: * an <code>IOException</code> may be thrown if the
061: * output stream has been closed.
062: */
063: public abstract void write(int b) throws IOException;
064:
065: /**
066: * Writes <code>b.length</code> bytes from the specified byte array
067: * to this output stream. The general contract for <code>write(b)</code>
068: * is that it should have exactly the same effect as the call
069: * <code>write(b, 0, b.length)</code>.
070: *
071: * @param b the data.
072: * @exception IOException if an I/O error occurs.
073: * @see java.io.OutputStream#write(byte[], int, int)
074: */
075: public void write(byte b[]) throws IOException {
076: write(b, 0, b.length);
077: }
078:
079: /**
080: * Writes <code>len</code> bytes from the specified byte array
081: * starting at offset <code>off</code> to this output stream.
082: * The general contract for <code>write(b, off, len)</code> is that
083: * some of the bytes in the array <code>b</code> are written to the
084: * output stream in order; element <code>b[off]</code> is the first
085: * byte written and <code>b[off+len-1]</code> is the last byte written
086: * by this operation.
087: * <p>
088: * The <code>write</code> method of <code>OutputStream</code> calls
089: * the write method of one argument on each of the bytes to be
090: * written out. Subclasses are encouraged to override this method and
091: * provide a more efficient implementation.
092: * <p>
093: * If <code>b</code> is <code>null</code>, a
094: * <code>NullPointerException</code> is thrown.
095: * <p>
096: * If <code>off</code> is negative, or <code>len</code> is negative, or
097: * <code>off+len</code> is greater than the length of the array
098: * <code>b</code>, then an <tt>IndexOutOfBoundsException</tt> is thrown.
099: *
100: * @param b the data.
101: * @param off the start offset in the data.
102: * @param len the number of bytes to write.
103: * @exception IOException if an I/O error occurs. In particular,
104: * an <code>IOException</code> is thrown if the output
105: * stream is closed.
106: */
107: public void write(byte b[], int off, int len) throws IOException {
108: if (b == null) {
109: throw new NullPointerException();
110: } else if ((off < 0) || (off > b.length) || (len < 0)
111: || ((off + len) > b.length) || ((off + len) < 0)) {
112: throw new IndexOutOfBoundsException();
113: } else if (len == 0) {
114: return;
115: }
116: for (int i = 0; i < len; i++) {
117: write(b[off + i]);
118: }
119: }
120:
121: /**
122: * Flushes this output stream and forces any buffered output bytes
123: * to be written out. The general contract of <code>flush</code> is
124: * that calling it is an indication that, if any bytes previously
125: * written have been buffered by the implementation of the output
126: * stream, such bytes should immediately be written to their
127: * intended destination.
128: * <p>
129: * If the intended destination of this stream is an abstraction provided by
130: * the underlying operating system, for example a file, then flushing the
131: * stream guarantees only that bytes previously written to the stream are
132: * passed to the operating system for writing; it does not guarantee that
133: * they are actually written to a physical device such as a disk drive.
134: * <p>
135: * The <code>flush</code> method of <code>OutputStream</code> does nothing.
136: *
137: * @exception IOException if an I/O error occurs.
138: */
139: public void flush() throws IOException {
140: }
141:
142: /**
143: * Closes this output stream and releases any system resources
144: * associated with this stream. The general contract of <code>close</code>
145: * is that it closes the output stream. A closed stream cannot perform
146: * output operations and cannot be reopened.
147: * <p>
148: * The <code>close</code> method of <code>OutputStream</code> does nothing.
149: *
150: * @exception IOException if an I/O error occurs.
151: */
152: public void close() throws IOException {
153: }
154:
155: }
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