/*
* #%L
* Talend :: ESB :: Job :: API
* %%
* Copyright (C) 2011 - 2012 Talend Inc.
* %%
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
* #L%
*/
// ============================================================================
//
// Copyright (C) 2006-2016 Talend Inc. - www.talend.com
//
// This source code is available under agreement available at
// %InstallDIR%\features\org.talend.rcp.branding.%PRODUCTNAME%\%PRODUCTNAME%license.txt
//
// You should have received a copy of the agreement
// along with this program; if not, write to Talend SA
// 9 rue Pages 92150 Suresnes, France
//
// ============================================================================
package routines.system;
import java.io.IOException;
import java.io.Writer;
/**
* @(#)BufferedWriter.java 1.26 03/12/19
*
* @see java.io.BuffferedWriter
* @author xzhang
*/
public class BufferedOutput extends java.io.Writer {
private Writer out;
private char cb[];
private int nChars, nextChar;
private static int defaultCharBufferSize = 8192;
/**
* Line separator string. This is the value of the line.separator property at the moment that the stream was
* created.
*/
private String lineSeparator;
/**
* Create a buffered character-output stream that uses a default-sized output buffer.
*
* @param out A Writer
*/
public BufferedOutput(Writer out) {
this(out, defaultCharBufferSize);
}
/**
* Create a new buffered character-output stream that uses an output buffer of the given size.
*
* @param out A Writer
* @param sz Output-buffer size, a positive integer
*
* @exception IllegalArgumentException If sz is <= 0
*/
public BufferedOutput(Writer out, int sz) {
super(out);
if (sz <= 0)
throw new IllegalArgumentException("Buffer size <= 0"); //$NON-NLS-1$
this.out = out;
cb = new char[sz];
nChars = sz;
nextChar = 0;
lineSeparator = (String) java.security.AccessController.doPrivileged(new sun.security.action.GetPropertyAction(
"line.separator")); //$NON-NLS-1$
}
/** Check to make sure that the stream has not been closed */
private void ensureOpen() throws IOException {
if (out == null)
throw new IOException("Stream closed"); //$NON-NLS-1$
}
/**
* Flush the output buffer to the underlying character stream, without flushing the stream itself. This method is
* non-private only so that it may be invoked by PrintStream.
*/
void flushBuffer() throws IOException {
synchronized (lock) {
ensureOpen();
if (nextChar == 0)
return;
out.write(cb, 0, nextChar);
// Flush the buffer of inside writer.
out.flush();
nextChar = 0;
}
}
/**
* Write a single character.
*
* @exception IOException If an I/O error occurs
*/
public void write(int c) throws IOException {
synchronized (lock) {
ensureOpen();
if (nextChar >= nChars)
flushBuffer();
cb[nextChar++] = (char) c;
}
}
/**
* Our own little min method, to avoid loading java.lang.Math if we've run out of file descriptors and we're trying
* to print a stack trace.
*/
private int min(int a, int b) {
if (a < b)
return a;
return b;
}
/**
* Write a portion of an array of characters.
*
* <p>
* Ordinarily this method stores characters from the given array into this stream's buffer, flushing the buffer to
* the underlying stream as needed. If the requested length is at least as large as the buffer, however, then this
* method will flush the buffer and write the characters directly to the underlying stream. Thus redundant
* <code>BufferedWriter</code>s will not copy data unnecessarily.
*
* @param cbuf A character array
* @param off Offset from which to start reading characters
* @param len Number of characters to write
*
* @exception IOException If an I/O error occurs
*/
public void write(char cbuf[], int off, int len) throws IOException {
synchronized (lock) {
ensureOpen();
if ((off < 0) || (off > cbuf.length) || (len < 0) || ((off + len) > cbuf.length) || ((off + len) < 0)) {
throw new IndexOutOfBoundsException();
} else if (len == 0) {
return;
}
if (len >= nChars) {
/*
* If the request length exceeds the size of the output buffer, flush the buffer and then write the data
* directly. In this way buffered streams will cascade harmlessly.
*/
flushBuffer();
out.write(cbuf, off, len);
return;
}
int b = off, t = off + len;
while (b < t) {
int d = min(nChars - nextChar, t - b);
System.arraycopy(cbuf, b, cb, nextChar, d);
b += d;
nextChar += d;
if (nextChar >= nChars)
flushBuffer();
}
}
}
/**
* Write a portion of a String.
*
* <p>
* If the value of the <tt>len</tt> parameter is negative then no characters are written. This is contrary to the
* specification of this method in the {@linkplain java.io.Writer#write(java.lang.String,int,int) superclass},
* which requires that an {@link IndexOutOfBoundsException} be thrown.
*
* @param s String to be written
* @param off Offset from which to start reading characters
* @param len Number of characters to be written
*
* @user xzhang
*
* @exception IOException If an I/O error occurs
*/
public void write(String s, int off, int len) throws IOException {
synchronized (lock) {
ensureOpen();
if (len >= nChars) {
/*
* If the request length exceeds the size of the output buffer, flush the buffer and then write the data
* directly. In this way buffered streams will cascade harmlessly.
*/
flushBuffer();
char[] cbuf = new char[len];
s.getChars(off, (off + len), cbuf, 0);
write(cbuf, 0, len);
return;
}
if (len > 0) {
/*
* If it doesn't write all char of string to buffer, flush buffer chars then put the String to buffer.
* Make sure String doesn't cut by ohter writer.
*/
if (nChars - nextChar < len) {
flushBuffer();
}
s.getChars(off, off + len, cb, nextChar);
nextChar += len;
if (nextChar >= nChars)
flushBuffer();
}
}
}
/**
* Write a line separator. The line separator string is defined by the system property <tt>line.separator</tt>,
* and is not necessarily a single newline ('\n') character.
*
* @exception IOException If an I/O error occurs
*/
public void newLine() throws IOException {
write(lineSeparator);
}
/**
* Flush the stream.
*
* @exception IOException If an I/O error occurs
*/
public void flush() throws IOException {
synchronized (lock) {
flushBuffer();
out.flush();
}
}
/**
* Close the stream.
*
* @exception IOException If an I/O error occurs
*/
public void close() throws IOException {
synchronized (lock) {
if (out == null)
return;
flushBuffer();
out.close();
out = null;
cb = null;
}
}
}