java.io

Class PrintStream

java.lang.Object

java.io.OutputStream

java.io.FilterOutputStream

java.io.PrintStream

public class PrintStream
extends FilterOutputStream

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 checkError() 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.

This class converts char's into byte's using the system default encoding.

Author:

Aaron M. Renn , Tom Tromey

Field Summary

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

Constructors

Constructor and Description
PrintStream(OutputStream out) This method intializes a new PrintStream object to write to the specified output sink.
PrintStream(OutputStream out, boolean auto_flush) This method intializes a new PrintStream object to write to the specified output sink.
PrintStream(OutputStream out, boolean auto_flush, String encoding) This method intializes a new PrintStream object to write to the specified output sink.

Method Summary

Modifier and Type	Method and Description
boolean	checkError() This method checks to see if an error has occurred on this stream.
void	close() This method closes this stream and all underlying streams.
void	flush() This method flushes any buffered bytes to the underlying stream and then flushes that stream as well.
void	print(boolean bool) This methods prints a boolean value to the stream.
void	print(char ch) This method prints a char to the stream.
void	print(char[] charArray) This method prints an array of characters to the stream.
void	print(double dnum) This method prints a double to the stream.
void	print(float fnum) This method prints a float to the stream.
void	print(int inum) This method prints an integer to the stream.
void	print(long lnum) This method prints a long to the stream.
void	print(Object obj) This method prints an Object to the stream.
void	print(String str) This method prints a String to the stream.
void	println() This method prints a line separator sequence to the stream.
void	println(boolean bool) This methods prints a boolean value to the stream.
void	println(char ch) This method prints a char to the stream.
void	println(char[] charArray) This method prints an array of characters to the stream.
void	println(double dnum) This method prints a double to the stream.
void	println(float fnum) This method prints a float to the stream.
void	println(int inum) This method prints an integer to the stream.
void	println(long lnum) This method prints a long to the stream.
void	println(Object obj) This method prints an Object to the stream.
void	println(String str) This method prints a String to the stream.
protected void	setError() This method can be called by subclasses to indicate that an error has occurred and should be reported by checkError.
void	write(byte[] buffer, int offset, int len) This method writes len bytes from the specified array starting at index offset into the array.
void	write(int oneByte) This method writes a byte of data to the stream.

Methods inherited from class java.io.FilterOutputStream

write

Methods inherited from class java.io.OutputStream

finalize

Methods inherited from class java.lang.Object

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

Constructor Detail

PrintStream

public PrintStream(OutputStream out)

This method intializes a new PrintStream object to write to the specified output sink.

Parameters:

out - The OutputStream to write to.

PrintStream

public PrintStream(OutputStream out,
                   boolean auto_flush)

This method intializes a new PrintStream 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.

Parameters:

out - The OutputStream to write to.

auto_flush - true to flush the stream after every line, false otherwise

PrintStream

public PrintStream(OutputStream out,
                   boolean auto_flush,
                   String encoding)
            throws UnsupportedEncodingException

This method intializes a new PrintStream 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.

Parameters:

out - The OutputStream to write to.

auto_flush - true to flush the stream after every line, false otherwise

encoding - The name of the character encoding to use for this object.

Throws:

UnsupportedEncodingException

Method Detail

checkError

public boolean checkError()

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 true forever for this stream. Before checking for an error condition, this method flushes the stream.

Returns:

true if an error has occurred, false otherwise

setError

protected void setError()

This method can be called by subclasses to indicate that an error has occurred and should be reported by checkError.

close

public void close()

This method closes this stream and all underlying streams.

Overrides:

close in class FilterOutputStream

flush

public void flush()

This method flushes any buffered bytes to the underlying stream and then flushes that stream as well.

Overrides:

flush in class FilterOutputStream

print

public void print(boolean bool)

This methods prints a boolean value to the stream. true values are printed as "true" and false values are printed as "false".

Parameters:

b - The boolean value to print

print

public void print(int inum)

This method prints an integer to the stream. The value printed is determined using the String.valueOf() method.

Parameters:

inum - The int value to be printed

print

public void print(long lnum)

This method prints a long to the stream. The value printed is determined using the String.valueOf() method.

Parameters:

lnum - The long value to be printed

print

public void print(float fnum)

This method prints a float to the stream. The value printed is determined using the String.valueOf() method.

Parameters:

fnum - The float value to be printed

print

public void print(double dnum)

This method prints a double to the stream. The value printed is determined using the String.valueOf() method.

Parameters:

dnum - The double value to be printed

print

public void print(Object obj)

This method prints an Object to the stream. The actual value printed is determined by calling the String.valueOf() method.

Parameters:

obj - The Object to print.

print

public void print(String str)

This method prints a String to the stream. The actual value printed depends on the system default encoding.

Parameters:

str - The String to print.

print

public void print(char ch)

This method prints a char to the stream. The actual value printed is determined by the character encoding in use.

Parameters:

ch - The char value to be printed

print

public void print(char[] charArray)

This method prints an array of characters to the stream. The actual value printed depends on the system default encoding.

Parameters:

s - The array of characters to print.

println

public void println()

This method prints a line separator sequence to the stream. The value printed is determined by the system property line.separator and is not necessarily the Unix '\n' newline character.

println

public void println(boolean bool)

This methods prints a boolean value to the stream. true values are printed as "true" and false values are printed as "false".

This method prints a line termination sequence after printing the value.

Parameters:

b - The boolean value to print

println

public void println(int inum)

This method prints an integer to the stream. The value printed is determined using the String.valueOf() method.

This method prints a line termination sequence after printing the value.

Parameters:

inum - The int value to be printed

println

public void println(long lnum)

This method prints a long to the stream. The value printed is determined using the String.valueOf() method.

This method prints a line termination sequence after printing the value.

Parameters:

lnum - The long value to be printed

println

public void println(float fnum)

This method prints a float to the stream. The value printed is determined using the String.valueOf() method.

This method prints a line termination sequence after printing the value.

Parameters:

fnum - The float value to be printed

println

public void println(double dnum)

This method prints a double to the stream. The value printed is determined using the String.valueOf() method.

This method prints a line termination sequence after printing the value.

Parameters:

dnum - The double value to be printed

println

public void println(Object obj)

This method prints an Object to the stream. The actual value printed is determined by calling the String.valueOf() method.

This method prints a line termination sequence after printing the value.

Parameters:

obj - The Object to print.

println

public void println(String str)

This method prints a String to the stream. The actual value printed depends on the system default encoding.

This method prints a line termination sequence after printing the value.

Parameters:

str - The String to print.

println

public void println(char ch)

This method prints a char to the stream. The actual value printed is determined by the character encoding in use.

This method prints a line termination sequence after printing the value.

Parameters:

ch - The char value to be printed

println

public void println(char[] charArray)

This method prints an array of characters to the stream. The actual value printed depends on the system default encoding.

This method prints a line termination sequence after printing the value.

Parameters:

s - The array of characters to print.

write

public void write(int oneByte)

This method writes a byte of data to the stream. If auto-flush is enabled, printing a newline character will cause the stream to be flushed after the character is written.

Overrides:

write in class FilterOutputStream

Parameters:

b - The byte to be written

write

public void write(byte[] buffer,
                  int offset,
                  int len)

This method writes len bytes from the specified array starting at index offset into the array.

Overrides:

write in class FilterOutputStream

Parameters:

buffer - The array of bytes to write

offset - The index into the array to start writing from

len - The number of bytes to write