java.io

Class PrintStream

Implemented Interfaces:
Appendable, AutoCloseable, Closeable, Flushable
Known Direct Subclasses:
LogStream

public class PrintStream
extends FilterOutputStream
implements Appendable

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.

Field Summary

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

PrintStream(File file)
This method initializes a new PrintStream object to write to the specified output File.
PrintStream(File file, String encoding)
This method initializes a new PrintStream object to write to the specified output File.
PrintStream(OutputStream out)
This method initializes a new PrintStream object to write to the specified output sink.
PrintStream(OutputStream out, boolean auto_flush)
This method initializes a new PrintStream object to write to the specified output sink.
PrintStream(OutputStream out, boolean auto_flush, String encoding)
This method initializes a new PrintStream object to write to the specified output sink.
PrintStream(String fileName)
This method initializes a new PrintStream object to write to the specified output File.
PrintStream(String fileName, String encoding)
This method initializes a new PrintStream object to write to the specified output File.

Method Summary

PrintStream
append(char c)
PrintStream
append(CharSequence cs)
PrintStream
append(CharSequence cs, int start, int end)
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.
PrintStream
format(String format, java.lang.Object... args)
PrintStream
format(Locale locale, String format, java.lang.Object... args)
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(Object obj)
This method prints an Object to the stream.
void
print(String str)
This method prints a String to the stream.
void
print(long lnum)
This method prints a long to the stream.
PrintStream
printf(String format, java.lang.Object... args)
PrintStream
printf(Locale locale, String format, java.lang.Object... args)
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(Object obj)
This method prints an Object to the stream.
void
println(String str)
This method prints a String to the stream.
void
println(long lnum)
This method prints a long 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

close, flush, write, write, write

Methods inherited from class java.io.OutputStream

close, flush, write, write, write

Methods inherited from class java.lang.Object

clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

PrintStream

public PrintStream(File file)
            throws FileNotFoundException
This method initializes a new PrintStream object to write to the specified output File. Doesn't autoflush.
Parameters:
file - The File to write to.
Throws:
FileNotFoundException - if an error occurs while opening the file.
Since:
1.5

PrintStream

public PrintStream(File file,
                   String encoding)
            throws FileNotFoundException,
                   UnsupportedEncodingException
This method initializes a new PrintStream object to write to the specified output File. Doesn't autoflush.
Parameters:
file - The File to write to.
encoding - The name of the character encoding to use for this object.
Throws:
FileNotFoundException - If an error occurs while opening the file.
UnsupportedEncodingException - If the charset specified by encoding is invalid.
Since:
1.5

PrintStream

public PrintStream(OutputStream out)
This method initializes a new PrintStream object to write to the specified output sink. Doesn't autoflush.
Parameters:
out - The OutputStream to write to.

PrintStream

public PrintStream(OutputStream out,
                   boolean auto_flush)
This method initializes 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 print or println call, when the write methods with array arguments are called, or when a single new-line character is written.

Parameters:
out - The OutputStream to write to.
auto_flush - true to flush the stream after every line, false otherwise
Throws:
NullPointerException - If out is null.

PrintStream

public PrintStream(OutputStream out,
                   boolean auto_flush,
                   String encoding)
            throws UnsupportedEncodingException
This method initializes 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 print or println call, when the write methods with array arguments are called, or when a single new-line 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:
NullPointerException - If out or encoding is null.

PrintStream

public PrintStream(String fileName)
            throws FileNotFoundException
This method initializes a new PrintStream object to write to the specified output File. Doesn't autoflush.
Parameters:
fileName - The name of the File to write to.
Throws:
FileNotFoundException - if an error occurs while opening the file,
Since:
1.5

PrintStream

public PrintStream(String fileName,
                   String encoding)
            throws FileNotFoundException,
                   UnsupportedEncodingException
This method initializes a new PrintStream object to write to the specified output File. Doesn't autoflush.
Parameters:
fileName - The name of the File to write to.
encoding - The name of the character encoding to use for this object.
Throws:
FileNotFoundException - if an error occurs while opening the file.
UnsupportedEncodingException - If the charset specified by encoding is invalid.
Since:
1.5

Method Details

append

public PrintStream append(char c)
Specified by:
append in interface Appendable
Since:
1.5

append

public PrintStream append(CharSequence cs)
Specified by:
append in interface Appendable
Since:
1.5

append

public PrintStream append(CharSequence cs,
                          int start,
                          int end)
Specified by:
append in interface Appendable
Since:
1.5

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

close

public void close()
This method closes this stream and all underlying streams.
Specified by:
close in interface Closeable
close in interface AutoCloseable
Overrides:
close in interface FilterOutputStream

flush

public void flush()
This method flushes any buffered bytes to the underlying stream and then flushes that stream as well.
Specified by:
flush in interface Flushable
Overrides:
flush in interface FilterOutputStream

format

public PrintStream format(String format,
                          java.lang.Object... args)
Since:
1.5

format

public PrintStream format(Locale locale,
                          String format,
                          java.lang.Object... args)
Since:
1.5

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:
bool - The boolean value 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:
charArray - The array of characters to print.

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(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(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(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(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

printf

public PrintStream printf(String format,
                          java.lang.Object... args)
Since:
1.5

printf

public PrintStream printf(Locale locale,
                          String format,
                          java.lang.Object... args)
Since:
1.5

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:
bool - The boolean value 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:
charArray - The array of characters to print.

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(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(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(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(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

setError

protected void setError()
This method can be called by subclasses to indicate that an error has occurred and should be reported by checkError.

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 interface 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

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 interface FilterOutputStream
Parameters:
oneByte - The byte to be written

PrintStream.java -- OutputStream for printing output Copyright (C) 1998, 1999, 2001, 2003, 2004, 2005, 2006 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 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.