author | henryjen |
Tue, 10 Jun 2014 16:18:54 -0700 | |
changeset 24865 | 09b1d992ca72 |
parent 5506 | 202f599c92aa |
permissions | -rw-r--r-- |
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/* |
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* Copyright (c) 1994, 2003, Oracle and/or its affiliates. All rights reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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* |
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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. Oracle designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Oracle in the LICENSE file that accompanied this code. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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* or visit www.oracle.com if you need additional information or have any |
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* questions. |
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*/ |
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package java.io; |
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/** |
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* The class implements a buffered output stream. By setting up such |
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* an output stream, an application can write bytes to the underlying |
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* output stream without necessarily causing a call to the underlying |
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* system for each byte written. |
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* |
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* @author Arthur van Hoff |
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24865
09b1d992ca72
8044740: Convert all JDK versions used in @since tag to 1.n[.n] in jdk repo
henryjen
parents:
5506
diff
changeset
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* @since 1.0 |
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*/ |
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public |
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class BufferedOutputStream extends FilterOutputStream { |
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/** |
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* The internal buffer where data is stored. |
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*/ |
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protected byte buf[]; |
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/** |
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* The number of valid bytes in the buffer. This value is always |
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* in the range <tt>0</tt> through <tt>buf.length</tt>; elements |
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* <tt>buf[0]</tt> through <tt>buf[count-1]</tt> contain valid |
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* byte data. |
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*/ |
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protected int count; |
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/** |
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* Creates a new buffered output stream to write data to the |
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* specified underlying output stream. |
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* |
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* @param out the underlying output stream. |
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*/ |
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public BufferedOutputStream(OutputStream out) { |
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this(out, 8192); |
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} |
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/** |
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* Creates a new buffered output stream to write data to the |
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* specified underlying output stream with the specified buffer |
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* size. |
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* |
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* @param out the underlying output stream. |
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* @param size the buffer size. |
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* @exception IllegalArgumentException if size <= 0. |
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*/ |
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public BufferedOutputStream(OutputStream out, int size) { |
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super(out); |
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if (size <= 0) { |
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throw new IllegalArgumentException("Buffer size <= 0"); |
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} |
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buf = new byte[size]; |
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} |
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/** Flush the internal buffer */ |
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private void flushBuffer() throws IOException { |
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if (count > 0) { |
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out.write(buf, 0, count); |
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count = 0; |
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} |
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} |
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/** |
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* Writes the specified byte to this buffered output stream. |
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* |
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* @param b the byte to be written. |
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* @exception IOException if an I/O error occurs. |
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*/ |
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public synchronized void write(int b) throws IOException { |
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if (count >= buf.length) { |
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flushBuffer(); |
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} |
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buf[count++] = (byte)b; |
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} |
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/** |
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* Writes <code>len</code> bytes from the specified byte array |
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* starting at offset <code>off</code> to this buffered output stream. |
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* |
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* <p> Ordinarily this method stores bytes from the given array into this |
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* stream's buffer, flushing the buffer to the underlying output stream as |
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* needed. If the requested length is at least as large as this stream's |
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* buffer, however, then this method will flush the buffer and write the |
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* bytes directly to the underlying output stream. Thus redundant |
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* <code>BufferedOutputStream</code>s will not copy data unnecessarily. |
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* |
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* @param b the data. |
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* @param off the start offset in the data. |
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* @param len the number of bytes to write. |
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* @exception IOException if an I/O error occurs. |
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*/ |
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public synchronized void write(byte b[], int off, int len) throws IOException { |
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if (len >= buf.length) { |
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/* If the request length exceeds the size of the output buffer, |
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flush the output buffer and then write the data directly. |
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In this way buffered streams will cascade harmlessly. */ |
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flushBuffer(); |
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out.write(b, off, len); |
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return; |
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} |
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if (len > buf.length - count) { |
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flushBuffer(); |
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} |
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System.arraycopy(b, off, buf, count, len); |
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count += len; |
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} |
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/** |
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* Flushes this buffered output stream. This forces any buffered |
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* output bytes to be written out to the underlying output stream. |
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* |
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* @exception IOException if an I/O error occurs. |
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* @see java.io.FilterOutputStream#out |
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*/ |
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public synchronized void flush() throws IOException { |
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flushBuffer(); |
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out.flush(); |
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} |
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} |