Mega Code Archive
A PrintWriter that also sends its output to a log stream
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/*
* Copyright 2005 Joe Walker
*
* 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.
*/
import java.io.BufferedWriter;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.PrintWriter;
import java.io.Writer;
import org.apache.commons.logging.LogFactory;
import org.apache.commons.logging.Log;
/**
* A PrintWriter that also sends its output to a log stream
* @author Joe Walker [joe at getahead dot ltd dot uk]
*/
public class DebuggingPrintWriter extends PrintWriter
{
/**
* Create a new PrintWriter, without automatic line flushing.
* @param prefix A tag to prefix lines with for debugging purposes
* @param out A character-output stream
*/
public DebuggingPrintWriter(String prefix, Writer out)
{
super(out, false);
this.prefix = prefix;
}
/**
* Create a new PrintWriter.
* @param prefix A tag to prefix lines with for debugging purposes
* @param out A character-output stream
* @param autoFlush A boolean; if true, the println() methods will flush the output buffer
*/
public DebuggingPrintWriter(String prefix, Writer out, boolean autoFlush)
{
super(out, autoFlush);
this.prefix = prefix;
}
/**
* Create a new PrintWriter, without automatic line flushing, from an
* existing OutputStream. This convenience constructor creates the
* necessary intermediate OutputStreamWriter, which will convert characters
* into bytes using the default character encoding.
* @param prefix A tag to prefix lines with for debugging purposes
* @param out An output stream
* @see java.io.OutputStreamWriter#OutputStreamWriter(java.io.OutputStream)
*/
public DebuggingPrintWriter(String prefix, OutputStream out)
{
super(out, false);
this.prefix = prefix;
}
/**
* Create a new PrintWriter from an existing OutputStream. This convenience
* constructor creates the necessary intermediate OutputStreamWriter, which
* will convert characters into bytes using the default character encoding.
* @param prefix A tag to prefix lines with for debugging purposes
* @param out An output stream
* @param autoFlush A boolean; if true, the println() methods will flush the output buffer
* @see java.io.OutputStreamWriter#OutputStreamWriter(java.io.OutputStream)
*/
public DebuggingPrintWriter(String prefix, OutputStream out, boolean autoFlush)
{
super(new BufferedWriter(new OutputStreamWriter(out)), autoFlush);
this.prefix = prefix;
}
/* (non-Javadoc)
* @see java.io.PrintWriter#print(boolean)
*/
@Override
public void print(boolean x)
{
super.print(x);
buffer.append(x);
}
/* (non-Javadoc)
* @see java.io.PrintWriter#print(char)
*/
@Override
public void print(char x)
{
super.print(x);
buffer.append(x);
}
/* (non-Javadoc)
* @see java.io.PrintWriter#print(int)
*/
@Override
public void print(int x)
{
super.print(x);
buffer.append(x);
}
/* (non-Javadoc)
* @see java.io.PrintWriter#print(long)
*/
@Override
public void print(long x)
{
super.print(x);
buffer.append(x);
}
/* (non-Javadoc)
* @see java.io.PrintWriter#print(float)
*/
@Override
public void print(float x)
{
super.print(x);
buffer.append(x);
}
/* (non-Javadoc)
* @see java.io.PrintWriter#print(double)
*/
@Override
public void print(double x)
{
super.print(x);
buffer.append(x);
}
/* (non-Javadoc)
* @see java.io.PrintWriter#print(char[])
*/
@Override
public void print(char[] x)
{
super.print(x);
buffer.append(x);
}
/* (non-Javadoc)
* @see java.io.PrintWriter#print(java.lang.String)
*/
@Override
public void print(String x)
{
super.print(x);
buffer.append(x);
}
/* (non-Javadoc)
* @see java.io.PrintWriter#print(java.lang.Object)
*/
@Override
public void print(Object x)
{
super.print(x);
buffer.append(x);
}
/* (non-Javadoc)
* @see java.io.PrintWriter#println()
*/
@Override
public void println()
{
synchronized (lock)
{
printBuffer();
super.println();
}
}
/* (non-Javadoc)
* @see java.io.PrintWriter#println(boolean)
*/
@Override
public void println(boolean x)
{
synchronized (lock)
{
printBuffer();
super.println(x);
}
}
/* (non-Javadoc)
* @see java.io.PrintWriter#println(char)
*/
@Override
public void println(char x)
{
synchronized (lock)
{
printBuffer();
super.println(x);
}
}
/* (non-Javadoc)
* @see java.io.PrintWriter#println(int)
*/
@Override
public void println(int x)
{
synchronized (lock)
{
printBuffer();
super.println(x);
}
}
/* (non-Javadoc)
* @see java.io.PrintWriter#println(long)
*/
@Override
public void println(long x)
{
synchronized (lock)
{
printBuffer();
super.println(x);
}
}
/* (non-Javadoc)
* @see java.io.PrintWriter#println(float)
*/
@Override
public void println(float x)
{
synchronized (lock)
{
printBuffer();
super.println(x);
}
}
/* (non-Javadoc)
* @see java.io.PrintWriter#println(double)
*/
@Override
public void println(double x)
{
synchronized (lock)
{
printBuffer();
super.println(x);
}
}
/* (non-Javadoc)
* @see java.io.PrintWriter#println(char[])
*/
@Override
public void println(char[] x)
{
synchronized (lock)
{
printBuffer();
super.println(x);
}
}
/* (non-Javadoc)
* @see java.io.PrintWriter#println(java.lang.String)
*/
@Override
public void println(String x)
{
synchronized (lock)
{
printBuffer();
super.println(x);
}
}
/* (non-Javadoc)
* @see java.io.PrintWriter#println(java.lang.Object)
*/
@Override
public void println(Object x)
{
synchronized (lock)
{
printBuffer();
super.println(x);
}
}
/**
* Write the characters in the print buffer out to the stream
*/
private void printBuffer()
{
if (buffer.length() > 0)
{
log.debug(prefix + buffer.toString());
buffer.setLength(0);
}
}
/**
* How to we prefix all the debugging lines?
* @return the prefix
*/
public String getPrefix()
{
return prefix;
}
/**
* How to we prefix all the debugging lines?
* @param prefix the prefix to set
*/
public void setPrefix(String prefix)
{
this.prefix = prefix;
}
/**
* How to we prefix all the debugging lines?
*/
private String prefix;
/**
* A buffer where we store stuff before a newline
*/
protected final StringBuffer buffer = new StringBuffer();
/**
* The log stream
*/
private static final Log log = LogFactory.getLog(DebuggingPrintWriter.class);
}
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