com.mckoi.util
Class LengthMarkedBufferedInputStream

java.lang.Object
  java.io.InputStream
      java.io.FilterInputStream
          com.mckoi.util.LengthMarkedBufferedInputStream

All Implemented Interfaces:

java.io.Closeable

public final class LengthMarkedBufferedInputStream
extends java.io.FilterInputStream

Reads a command block on the underlying stream that is constrained by a length marker preceeding the command. This can be used as a hack work around for non-blocking IO because we know ahead of time how much data makes up the next block of information over the stream.

Author:

Tobias Downer

Constructor Summary

LengthMarkedBufferedInputStream(java.io.InputStream in)
The Constructor.

Method Summary

int	available()
void	blockForCommand() Blocks until a complete command has been read in.
boolean	markSupported()
boolean	pollForCommand(int max_size) Checks to see if there is a complete command waiting on the input stream.
int	read()
int	read(byte[] b, int off, int len)

Methods inherited from class java.io.FilterInputStream

close, mark, read, reset, skip

Methods inherited from class java.lang.Object

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

Constructor Detail

LengthMarkedBufferedInputStream

public LengthMarkedBufferedInputStream(java.io.InputStream in)

The Constructor.

Method Detail

read

public int read()
         throws java.io.IOException

Overrides:

read in class java.io.FilterInputStream

Throws:

java.io.IOException

read

public int read(byte[] b,
                int off,
                int len)
         throws java.io.IOException

Overrides:

read in class java.io.FilterInputStream

Throws:

java.io.IOException

available

public int available()
              throws java.io.IOException

Overrides:

available in class java.io.FilterInputStream

Throws:

java.io.IOException

markSupported

public boolean markSupported()

Overrides:

markSupported in class java.io.FilterInputStream

pollForCommand

public boolean pollForCommand(int max_size)
                       throws java.io.IOException

Checks to see if there is a complete command waiting on the input stream. Returns true if there is. If this method returns true then it is safe to go ahead and process a single command from this stream. This will return true only once while there is a command pending until that command is completely read in.

'max_size' is the maximum number of bytes we are allowing before an IOException is thrown.

Throws:

java.io.IOException

blockForCommand

public void blockForCommand()
                     throws java.io.IOException

Blocks until a complete command has been read in.

Throws:

java.io.IOException