printstream.java

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/* PrintStream.java -- OutputStream for printing output
   Copyright (C) 1998 Free Software Foundation, Inc.

This file is part of GNU Classpath.

GNU Classpath is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.
 
GNU Classpath 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 for more details.

You should have received a copy of the GNU General Public License
along with GNU Classpath; see the file COPYING.  If not, write to the
Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA.

Linking this library statically or dynamically with other modules is
making a combined work based on this library.  Thus, the terms and
conditions of the GNU General Public License cover the whole
combination.

As a special exception, the copyright holders of this library give you
permission to link this library with independent modules to produce an
executable, regardless of the license terms of these independent
modules, and to copy and distribute the resulting executable under
terms of your choice, provided that you also meet, for each linked
independent module, the terms and conditions of the license of that
module.  An independent module is a module which is not derived from
or based on this library.  If you modify this library, you may extend
this exception to your version of the library, but you are not
obligated to do so.  If you do not wish to do so, delete this
exception statement from your version. */


package java.io;

/**
  * This class prints Java primitive values and object to a stream as
  * text.  None of the methods in this class throw an exception.  However,
  * errors can be detected by calling the <code>checkError()</code> method.
  * Additionally, this stream can be designated as "autoflush" when 
  * created so that any writes are automatically flushed to the underlying
  * output sink when the current line is terminated.
  * <p>
  * <b>Note that this class is deprecated</b>.  It exists for backward  
  * compatibility only.  New code should be written to use 
  * <code>PrintWriter</code> instead.  
  * <p>
  * This class converts char's into byte's using the system default encoding.
  *
  * @version 0.0
  *
  * @author Aaron M. Renn ([e-mail])
  */
public class PrintStream extends FilterOutputStream
{

/*
 * Ok, why is this class deprecated?  It could easily have been extended
 * to support character encodings.  In fact, PrintWriter is basically a
 * superset of this except for the write() methods.  So let's do something
 * tricky here and just redirect calls in this class to a hidden PrintWriter
 * instance.  All the functionality goes there since that is the 'real'
 * class.  The big win of doing this way is that the default character 
 * encoding is done automagicially by the PrintWriter tree!
 */

/*************************************************************************/

/*
 * Instance Variables
 */

/**
  * This boolean indicates whether or not an error has ever occured
  * on this stream.
  */
private boolean error_occurred;

/**
  * This is <code>true</code> if auto-flush is enabled, <code>false</code> otherwise
  */
private boolean auto_flush;

/**
  * The PrintWriter instance this object writes to
  */
private PrintWriter pw;

/**
  * Lets us know if the stream is closed
  */
private boolean closed;

/*************************************************************************/

/*
 * Constructors
 */

/**
  * This method intializes a new <code>PrintStream</code> object to write
  * to the specified output sink.  Note that this class is deprecated in
  * favor of <code>PrintWriter</code>.
  *
  * @param out The <code>OutputStream</code> to write to.
  */
public
PrintStream(OutputStream out)
{
  this(out, false);
}

/*************************************************************************/

/**
  * This method intializes a new <code>PrintStream</code> object to write
  * to the specified output sink.  This constructor also allows "auto-flush"
  * functionality to be specified where the stream will be flushed after
  * every line is terminated or newline character is written.
  * <p>
  * Note that this class is deprecated in favor of <code>PrintWriter</code>.
  *
  * @param out The <code>OutputStream</code> to write to.
  * @param auto_flush <code>true</code> to flush the stream after every line, <code>false</code> otherwise
  */
public
PrintStream(OutputStream out, boolean auto_flush)
{
  super(out);

  pw = new PrintWriter(out, auto_flush);
  this.auto_flush = auto_flush;
}

/*************************************************************************/

/*
 * Instance Methods
 */

/**
  * This method checks to see if an error has occurred on this stream.  Note
  * that once an error has occurred, this method will continue to report
  * <code>true</code> forever for this stream.  Before checking for an
  * error condition, this method flushes the stream.
  *
  * @return <code>true</code> if an error has occurred, <code>false</code> otherwise
  */
public boolean
checkError()
{
  if (!closed)
    pw.flush();

  if (pw.checkError() | error_occurred)
    return(true);
  else
    return(false);
}

/*************************************************************************/

/**
  * This method can be called by subclasses to indicate that an error
  * has occurred and should be reported by <code>checkError</code>.
  */
protected void
setError()
{
  error_occurred = true;
}
  
/*************************************************************************/

/**
  * This method closes this stream and all underlying streams.
  */
public synchronized void
close()
{
  pw.close();
  closed = true;
}

/*************************************************************************/

/**
  * This method flushes any buffered bytes to the underlying stream and
  * then flushes that stream as well.
  */
public void
flush()
{
  pw.flush();
}

/*************************************************************************/

/**
  * This methods prints a boolean value to the stream.  <code>true</code>
  * values are printed as "true" and <code>false</code> values are printed
  * as "false".
  *
  * @param b The <code>boolean</code> value to print
  */
public void
print(boolean b)
{
  pw.print(b);
}

/*************************************************************************/

/**
  * This method prints a char to the stream.  The actual value printed is
  * determined by the character encoding in use.
  *
  * @param c The <code>char</code> value to be printed
  */
public void
print(char c)
{
  pw.print(c);

  if (auto_flush)
    if ((c == '\r') || (c == '\n'))
      flush();    
}

/*************************************************************************/

/**
  * This method prints an integer to the stream.  The value printed is
  * determined using the <code>String.valueOf()</code> method.
  *
  * @param i The <code>int</code> value to be printed
  */
public void
print(int i)
{
  pw.print(i);
}

/*************************************************************************/

/**
  * This method prints a long to the stream.  The value printed is
  * determined using the <code>String.valueOf()</code> method.
  *
  * @param l The <code>long</code> value to be printed
  */
public void
print(long l)
{
  pw.print(l);
}

/*************************************************************************/

/**
  * This method prints a float to the stream.  The value printed is
  * determined using the <code>String.valueOf()</code> method.
  *
  * @param f The <code>float</code> value to be printed
  */
public void
print(float f)
{
  pw.print(f);
}

/*************************************************************************/

/**
  * This method prints a double to the stream.  The value printed is
  * determined using the <code>String.valueOf()</code> method.
  *
  * @param d The <code>double</code> value to be printed
  */
public void
print(double d)
{