22.9

java.io.FilterInputStream

THE PACKAGE JAVA.IO

22.9 The Class

java.io.FilterInputStream

A

FilterInputStream

 contains some other input stream, which it uses as its

basic source of data, possibly transforming the data along the way or providing

additional functionality. The class

FilterInputStream

 itself simply overrides all

methods of

InputStream

 with versions that pass all requests to the contained

input stream. Subclasses of

FilterInputStream

 may further override some of

these methods and may also provide additional methods and fields.

public class FilterInputStream extends InputStream {

protected InputStream in;

protected FilterInputStream(InputStream in);

public int read() throws IOException;

public int read(byte[] b)

throws IOException, NullPointerException;

public int read(byte[] b, int off, int len)

throws IOException, NullPointerException,

IndexOutOfBoundsException;

public long skip(long n) throws IOException;

public int available() throws IOException;

public void close() throws IOException;

public void mark(int readlimit);

public void reset() throws IOException;

public boolean markSupported();

}

22.9.1

protected InputStream in;

The input stream to be filtered.

22.9.2

protected FilterInputStream(InputStream in)

This constructor initializes a newly created

FilterInputStream

 by assigning the

argument

in

 to the field

this.in

 so as to remember it for later use.

22.9.3

public int read() throws IOException

This method simply performs

in.read()

 and returns the result.

Implements the

read

 method of

InputStream

 ( 22.3.1).

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