jdk/src/share/classes/java/io/FilterOutputStream.java
changeset 2 90ce3da70b43
child 5506 202f599c92aa
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/io/FilterOutputStream.java	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,162 @@
+/*
+ * Copyright 1994-1999 Sun Microsystems, Inc.  All Rights Reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+package java.io;
+
+/**
+ * This class is the superclass of all classes that filter output
+ * streams. These streams sit on top of an already existing output
+ * stream (the <i>underlying</i> output stream) which it uses as its
+ * basic sink of data, but possibly transforming the data along the
+ * way or providing additional functionality.
+ * <p>
+ * The class <code>FilterOutputStream</code> itself simply overrides
+ * all methods of <code>OutputStream</code> with versions that pass
+ * all requests to the underlying output stream. Subclasses of
+ * <code>FilterOutputStream</code> may further override some of these
+ * methods as well as provide additional methods and fields.
+ *
+ * @author  Jonathan Payne
+ * @since   JDK1.0
+ */
+public
+class FilterOutputStream extends OutputStream {
+    /**
+     * The underlying output stream to be filtered.
+     */
+    protected OutputStream out;
+
+    /**
+     * Creates an output stream filter built on top of the specified
+     * underlying output stream.
+     *
+     * @param   out   the underlying output stream to be assigned to
+     *                the field <tt>this.out</tt> for later use, or
+     *                <code>null</code> if this instance is to be
+     *                created without an underlying stream.
+     */
+    public FilterOutputStream(OutputStream out) {
+        this.out = out;
+    }
+
+    /**
+     * Writes the specified <code>byte</code> to this output stream.
+     * <p>
+     * The <code>write</code> method of <code>FilterOutputStream</code>
+     * calls the <code>write</code> method of its underlying output stream,
+     * that is, it performs <tt>out.write(b)</tt>.
+     * <p>
+     * Implements the abstract <tt>write</tt> method of <tt>OutputStream</tt>.
+     *
+     * @param      b   the <code>byte</code>.
+     * @exception  IOException  if an I/O error occurs.
+     */
+    public void write(int b) throws IOException {
+        out.write(b);
+    }
+
+    /**
+     * Writes <code>b.length</code> bytes to this output stream.
+     * <p>
+     * The <code>write</code> method of <code>FilterOutputStream</code>
+     * calls its <code>write</code> method of three arguments with the
+     * arguments <code>b</code>, <code>0</code>, and
+     * <code>b.length</code>.
+     * <p>
+     * Note that this method does not call the one-argument
+     * <code>write</code> method of its underlying stream with the single
+     * argument <code>b</code>.
+     *
+     * @param      b   the data to be written.
+     * @exception  IOException  if an I/O error occurs.
+     * @see        java.io.FilterOutputStream#write(byte[], int, int)
+     */
+    public void write(byte b[]) throws IOException {
+        write(b, 0, b.length);
+    }
+
+    /**
+     * Writes <code>len</code> bytes from the specified
+     * <code>byte</code> array starting at offset <code>off</code> to
+     * this output stream.
+     * <p>
+     * The <code>write</code> method of <code>FilterOutputStream</code>
+     * calls the <code>write</code> method of one argument on each
+     * <code>byte</code> to output.
+     * <p>
+     * Note that this method does not call the <code>write</code> method
+     * of its underlying input stream with the same arguments. Subclasses
+     * of <code>FilterOutputStream</code> should provide a more efficient
+     * implementation of this method.
+     *
+     * @param      b     the data.
+     * @param      off   the start offset in the data.
+     * @param      len   the number of bytes to write.
+     * @exception  IOException  if an I/O error occurs.
+     * @see        java.io.FilterOutputStream#write(int)
+     */
+    public void write(byte b[], int off, int len) throws IOException {
+        if ((off | len | (b.length - (len + off)) | (off + len)) < 0)
+            throw new IndexOutOfBoundsException();
+
+        for (int i = 0 ; i < len ; i++) {
+            write(b[off + i]);
+        }
+    }
+
+    /**
+     * Flushes this output stream and forces any buffered output bytes
+     * to be written out to the stream.
+     * <p>
+     * The <code>flush</code> method of <code>FilterOutputStream</code>
+     * calls the <code>flush</code> method of its underlying output stream.
+     *
+     * @exception  IOException  if an I/O error occurs.
+     * @see        java.io.FilterOutputStream#out
+     */
+    public void flush() throws IOException {
+        out.flush();
+    }
+
+    /**
+     * Closes this output stream and releases any system resources
+     * associated with the stream.
+     * <p>
+     * The <code>close</code> method of <code>FilterOutputStream</code>
+     * calls its <code>flush</code> method, and then calls the
+     * <code>close</code> method of its underlying output stream.
+     *
+     * @exception  IOException  if an I/O error occurs.
+     * @see        java.io.FilterOutputStream#flush()
+     * @see        java.io.FilterOutputStream#out
+     */
+    public void close() throws IOException {
+        try {
+          flush();
+        } catch (IOException ignored) {
+        }
+        out.close();
+    }
+}