| /* |
| * Copyright (c) 1994, 2003, Oracle and/or its affiliates. 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. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package java.io; |
| |
| /** |
| * The class implements a buffered output stream. By setting up such |
| * an output stream, an application can write bytes to the underlying |
| * output stream without necessarily causing a call to the underlying |
| * system for each byte written. |
| * |
| * @author Arthur van Hoff |
| * @since JDK1.0 |
| */ |
| public |
| class BufferedOutputStream extends FilterOutputStream { |
| /** |
| * The internal buffer where data is stored. |
| */ |
| protected byte buf[]; |
| |
| /** |
| * The number of valid bytes in the buffer. This value is always |
| * in the range <tt>0</tt> through <tt>buf.length</tt>; elements |
| * <tt>buf[0]</tt> through <tt>buf[count-1]</tt> contain valid |
| * byte data. |
| */ |
| protected int count; |
| |
| /** |
| * Creates a new buffered output stream to write data to the |
| * specified underlying output stream. |
| * |
| * @param out the underlying output stream. |
| */ |
| public BufferedOutputStream(OutputStream out) { |
| this(out, 8192); |
| } |
| |
| /** |
| * Creates a new buffered output stream to write data to the |
| * specified underlying output stream with the specified buffer |
| * size. |
| * |
| * @param out the underlying output stream. |
| * @param size the buffer size. |
| * @exception IllegalArgumentException if size <= 0. |
| */ |
| public BufferedOutputStream(OutputStream out, int size) { |
| super(out); |
| if (size <= 0) { |
| throw new IllegalArgumentException("Buffer size <= 0"); |
| } |
| buf = new byte[size]; |
| } |
| |
| /** Flush the internal buffer */ |
| private void flushBuffer() throws IOException { |
| if (count > 0) { |
| out.write(buf, 0, count); |
| count = 0; |
| } |
| } |
| |
| /** |
| * Writes the specified byte to this buffered output stream. |
| * |
| * @param b the byte to be written. |
| * @exception IOException if an I/O error occurs. |
| */ |
| public synchronized void write(int b) throws IOException { |
| if (count >= buf.length) { |
| flushBuffer(); |
| } |
| buf[count++] = (byte)b; |
| } |
| |
| /** |
| * Writes <code>len</code> bytes from the specified byte array |
| * starting at offset <code>off</code> to this buffered output stream. |
| * |
| * <p> Ordinarily this method stores bytes from the given array into this |
| * stream's buffer, flushing the buffer to the underlying output stream as |
| * needed. If the requested length is at least as large as this stream's |
| * buffer, however, then this method will flush the buffer and write the |
| * bytes directly to the underlying output stream. Thus redundant |
| * <code>BufferedOutputStream</code>s will not copy data unnecessarily. |
| * |
| * @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. |
| */ |
| public synchronized void write(byte b[], int off, int len) throws IOException { |
| if (len >= buf.length) { |
| /* If the request length exceeds the size of the output buffer, |
| flush the output buffer and then write the data directly. |
| In this way buffered streams will cascade harmlessly. */ |
| flushBuffer(); |
| out.write(b, off, len); |
| return; |
| } |
| if (len > buf.length - count) { |
| flushBuffer(); |
| } |
| System.arraycopy(b, off, buf, count, len); |
| count += len; |
| } |
| |
| /** |
| * Flushes this buffered output stream. This forces any buffered |
| * output bytes to be written out to the underlying output stream. |
| * |
| * @exception IOException if an I/O error occurs. |
| * @see java.io.FilterOutputStream#out |
| */ |
| public synchronized void flush() throws IOException { |
| flushBuffer(); |
| out.flush(); |
| } |
| } |