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Java in a Nutshell

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The java.io Package

24.69 java.io.Writer (JDK 1.1)

This abstract class is the superclass of all character output streams. It is an analog to OutputStream, which is the superclass of all byte output streams. Writer defines the basic write(), flush(), and close() methods that all character output streams provide.

The five versions of the write() method write a single character, a character array or subarray, or a string or substring to the destination of the stream. The most general version of this method--the one that writes a specified portion of a character array--is abstract and must be implemented by all subclasses. By default, the other write() methods are implemented in terms of this abstract one.

The flush() method is another abstract method that all subclasses must implement. It should force any output buffered by the stream to be written to its destination. If that destination is itself a character or byte output stream, it should invoke the flush() method of the destination stream as well.

The close() method is also abstract. Subclasses must implement this method so that it flushes and then closes the current stream, and also closes whatever destination stream it is connected to. Once the stream has been closed, any future calls to write() or flush() should throw an IOException.

public abstract class Writer extends Object {
    // Protected Constructors
            protected Writer();
            protected Writer(Object lock);
    // Protected Instance Variables
            protected Object lock;
    // Public Instance Methods
            public abstract void close() throws IOException;
            public abstract void flush() throws IOException;
            public void write(int c) throws IOException;
            public void write(char[] cbuf) throws IOException;
            public abstract void write(char[] cbuf, int off, int len) throws IOException;
            public void write(String str) throws IOException;
            public void write(String str, int off, int len) throws IOException;

Extended By:

BufferedWriter, CharArrayWriter, FilterWriter, OutputStreamWriter, PipedWriter, PrintWriter, StringWriter

Passed To:

BufferedWriter(), CharArrayWriter.writeTo(), FilterWriter(), PrintWriter()

Type Of:


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