com.android.io
Class NonClosingInputStream

java.lang.Object
  java.io.InputStream
      java.io.FilterInputStream
          com.android.io.NonClosingInputStream

All Implemented Interfaces:

java.io.Closeable

public class NonClosingInputStream
extends java.io.FilterInputStream

Wraps an InputStream to change its closing behavior: this makes it possible to ignore close operations or have them perform a InputStream.reset() instead (if supported by the underlying stream) or plain ignored.

This is useful to pass a stream to an XML parser or validator that automatically closes its input stream -- which makes it impossible to validate a stream and then parse it without reacquiring the stream.

Example of usage:

 // Get a stream that supports mark/reset in case the original does not
 InputStream buffered = new BufferedInputStream(source);
 // Mark the beginning of the stream and indicate how much buffering is acceptable
 buffered.mark(500000);
 // Wrap the stream so that closing it actually just resets it to the mark
 NonClosingInputStream stream = new NonClosingInputStream(buffered);
 stream.setCloseBehavior(CloseBehavior.RESET)
 // pass it to a schema validator (pseudo code, real code is way more verbose.)
 SAXParserFactory...newSAXParser().parse(stream) ...
 // the validator parser closes the stream, which resets it to the beginning
 // so passing it another parser will actually parse the whole stream
 SAXParser...parse(stream) ...
 

Nested Class Summary

static class

NonClosingInputStream.CloseBehavior

Field Summary

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

NonClosingInputStream(java.io.InputStream in)
Wraps an existing stream into this filtering stream.

Method Summary

void	close() Performs the requested close() operation, depending on the current NonClosingInputStream.CloseBehavior.
NonClosingInputStream.CloseBehavior	getCloseBehavior() Returns the current NonClosingInputStream.CloseBehavior.
NonClosingInputStream	setCloseBehavior(NonClosingInputStream.CloseBehavior closeBehavior) Changes the current NonClosingInputStream.CloseBehavior.

Methods inherited from class java.io.FilterInputStream

available, mark, markSupported, read, read, read, reset, skip

Methods inherited from class java.lang.Object

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

Constructor Detail

NonClosingInputStream

public NonClosingInputStream(@NonNull
                             java.io.InputStream in)

Wraps an existing stream into this filtering stream.

Parameters:

in - A non-null input stream.

Method Detail

getCloseBehavior

@NonNull
public NonClosingInputStream.CloseBehavior getCloseBehavior()

Returns the current NonClosingInputStream.CloseBehavior.

Returns:

the current NonClosingInputStream.CloseBehavior. Never null.

setCloseBehavior

public NonClosingInputStream setCloseBehavior(@NonNull
                                              NonClosingInputStream.CloseBehavior closeBehavior)

Changes the current NonClosingInputStream.CloseBehavior.

Parameters:

closeBehavior - A new non-null NonClosingInputStream.CloseBehavior.

Returns:

Self for chaining.

close

public void close()
           throws java.io.IOException

Performs the requested close() operation, depending on the current NonClosingInputStream.CloseBehavior.

Specified by:

close in interface java.io.Closeable

Overrides:

close in class java.io.FilterInputStream

Throws:

java.io.IOException