Print Streams

The java.io.PrintStream class is a subclass of FilterOutputStream. It is implemented by System.out and System.err. It allows very simple printing of both primitive values, objects, and string literals. It uses the platform's default character encoding to convert characters into bytes.

This class traps all IOExceptions. However you can test the error status with checkError(). This returns true if an error has occurred, false otherwise.

public boolean checkError()

The main use of the class is the exceptionally overloaded print() and println() methods. They differ in that println() adds an end-of-line character to whatever it prints while print() does not.

 public void print(boolean b)
 public void print(int i)
 public void print(long l)
 public void print(float f)
 public void print(double d)
 public void print(char s[])
 public void print(String s)
 public void print(Object obj)
 public void println()
 public void println(boolean x)
 public void println(char x)
 public void println(int x)
 public void println(long x)
 public void println(float x)
 public void println(double x)
 public void println(char x[])
 public void println(String x)
 public void println(Object x)
PrintStream is primarily intended for debugging. Otherwise it's unofficially deprecated in Java 1.1. You should use the PrintWriter class instead.


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Last Modified November 18, 1997
Copyright 1997 Elliotte Rusty Harold
elharo@metalab.unc.edu