Java in a Nutshell, 5th Edition [Electronic resources]

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PrintStreamjava.io

Java 1.0appendable closeable flushable

This class is a byte output stream that implements a number of methods for displaying textual representations of Java primitive data types. System.out and System.err are PrintStream objects. PrintStream converts characters to bytes using the platform's default charset, or the charset or encoding named in the PrintStream( ) constructor invocation. In Java 5.0, convenience constructors allow you to specify a file (either as a file name or a File object) as the destination of a PrintStream. Prior to Java 5.0 the destination had to be another OutputStream object.

The print( ) methods output standard textual representations of each data type. The println( ) methods do the same and follow the representations with newlines. Each method converts a Java primitive type to a String representation and outputs the resulting string. When an Object is passed to a print( ) or println( ), it is converted to a String by calling its toString( ) method. In Java 5.0, you can also use the printf( ) methods (or the format( ) methods that behave identically) for formatted output. These methods behave like the format( ) method of a java.util.Formatter object that uses the PrintStream as its destination.

This class implements the java.lang.Appendable interface in Java 5.0, which makes it suitable for use with a java.util.Formatter.

See also PrintWriter for a character output stream with similar functionality. And see DataOutputStream for a byte output stream that outputs binary, rather than textual, representations of Java's primitive types.

Figure 9-49. java.io.PrintStream

public class

PrintStream extends FilterOutputStream implements Appendable, Closeable { // Public Constructors

5.0 public

PrintStream (File

file ) throws FileNotFoundException;

5.0 public

PrintStream (String

fileName ) throws FileNotFoundException; public

PrintStream (OutputStream

out );

5.0 public

PrintStream (String

fileName , String

csn ) throws FileNotFoundException, UnsupportedEncodingException; public

PrintStream (OutputStream

out , boolean

autoFlush );

5.0 public

PrintStream (File

file , String

csn ) throws FileNotFoundException, UnsupportedEncodingException;

1.4 public

PrintStream (OutputStream

out , boolean

autoFlush , String

encoding ) throws UnsupportedEncodingException; // Public Instance Methods

5.0 public PrintStream

append (char

c );

5.0 public PrintStream

append (CharSequence

csq );

5.0 public PrintStream

append (CharSequence

csq , int

start , int

end ); public boolean

checkError ( ); public void

close ( ); Implements:Closeable

5.0 public PrintStream

format (String

format , Object...

args );

5.0 public PrintStream

format (java.util.Locale

l , String

format , Object...

args ); public void

print (double

d ); public void

print (float

f ); public void

print (char[ ]

s ); public void

print (Object

obj ); public void

print (String

s ); public void

print (long

l ); public void

print (boolean

b ); public void

print (char

c ); public void

print (int

i );

5.0 public PrintStream

printf (String

format , Object...

args );

5.0 public PrintStream

printf (java.util.Locale

l , String

format , Object...

args ); public void

println ( ); public void

println (char[ ]

x ); public void

println (double

x ); public void

println (Object

x ); public void

println (String

x ); public void

println (float

x ); public void

println (char

x ); public void

println (boolean

x ); public void

println (long

x ); public void

println (int

x ); // Methods Implementing Closeable public void

close ( ); // Public Methods Overriding FilterOutputStream public void

flush ( ); public void

write (int

b ); public void

write (byte[ ]

buf , int

off , int

len ); // Protected Instance Methods

1.1 protected void

setError ( ); }

Passed To

System.{setErr( ), setOut( )}, THRowable.printStackTrace( ), java.util.Formatter.Formatter( ), java.util.Properties.list( ), javax.xml.transform.TransformerException.printStackTrace( ), javax.xml.xpath.XPathException.printStackTrace( )

Type Of

System.{err, out}