org.expressionj.functions

Class EchoLogger

java.lang.Object

org.expressionj.functions.EchoLogger

public class EchoLogger
extends java.lang.Object

This class allows to log the result of the "echo" keyword in an output stream.

Constructor Summary

Constructors

Constructor and Description
EchoLogger()

Method Summary

Modifier and Type	Method and Description
static EchoLogger	getInstance() Return the unique instance.
void	log(java.lang.Object o) Log one Object to the underlying PrintStream or the standard output Stream.
void	setPrintStream(java.io.PrintStream stream) Set the printStream to use for the echo keyword.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

EchoLogger

public EchoLogger()

Method Detail

getInstance

public static EchoLogger getInstance()

Return the unique instance.

Returns:

the unique instance

setPrintStream

public void setPrintStream(java.io.PrintStream stream)

Set the printStream to use for the echo keyword. If the PrintStream to use is null, the standard output stream will be used instead. Note that there is a very simple way to redirect the result of a PrintStream to anything you want in Java. For example, the following class redirect the result of the stream to the standard error stream in Java.

 public class ErrorStream extends ByteArrayOutputStream {
    public ErrorStream() {
       super();
    }

   public void flush() throws IOException {
      synchronized (this) {
         super.flush();
         String result = this.toString();
         System.out.err(result);
         super.reset();
       }
    }
 }
 

A simple way to wrap an OutputStream like this one to a PrintStream is performed just by:

 ErrorStream errorStream = new ErrorStream();
 PrintStream stream = new PrintStream(errorStream);
 

Parameters:

stream - the PrintStream

log

public void log(java.lang.Object o)

Log one Object to the underlying PrintStream or the standard output Stream. This method will be invoked by the expression echo.

Parameters:

o - the Object

See Also:

ExprECHO