edu.rit.pj.cluster

Class BackendFileInputStream

java.lang.Object

java.io.InputStream

edu.rit.pj.cluster.BackendFileInputStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class BackendFileInputStream
extends java.io.InputStream

Class BackendFileInputStream provides an object in a job backend process that reads a sequential file in the job frontend process. A backend file input stream is not constructed directly, rather it is created by a factory method in class BackendFileReader.

Note: Class BackendFileInputStream does not do any buffering. Each method call sends a message to and receives a message from the job frontend. Consider layering a BufferedInputStream on top of the BackendFileInputStream.

Method Summary

Modifier and Type	Method and Description
void	close() Close this input stream.
int	read() Read a byte from this input stream.
int	read(byte[] buf) Read the given byte array from this input stream.
int	read(byte[] buf, int off, int len) Read a portion of the given byte array from this input stream.
long	skip(long len) Skip the given number of bytes from this input stream.

Methods inherited from class java.io.InputStream

available, mark, markSupported, reset

Methods inherited from class java.lang.Object

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

Method Detail

read

public int read()
         throws java.io.IOException

Read a byte from this input stream. The byte is returned as an int in the range 0 .. 255.

Specified by:

read in class java.io.InputStream

Returns:

Byte, or -1 if the end-of-stream was encountered.

Throws:

java.io.IOException - Thrown if an I/O error occurred.

read

public int read(byte[] buf)
         throws java.io.IOException

Read the given byte array from this input stream.

Overrides:

read in class java.io.InputStream

Parameters:

buf - Byte array.

Returns:

Number of bytes actually read, or -1 if the end-of-stream was encountered.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if buf is null.

java.io.IOException - Thrown if an I/O error occurred.

read

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

Read a portion of the given byte array from this input stream.

Overrides:

read in class java.io.InputStream

Parameters:

buf - Byte array.

off - Index of first byte to read.

len - Number of bytes to read.

Returns:

Number of bytes actually read, or -1 if the end-of-stream was encountered.

Throws:

java.lang.NullPointerException - (unchecked exception) Thrown if buf is null.

java.lang.IndexOutOfBoundsException - (unchecked exception) Thrown if off < 0, len < 0, or off+len > buf.length.

java.io.IOException - Thrown if an I/O error occurred.

skip

public long skip(long len)
          throws java.io.IOException

Skip the given number of bytes from this input stream.

Overrides:

skip in class java.io.InputStream

Parameters:

len - Number of bytes to skip.

Returns:

Number of bytes actually skipped.

Throws:

java.io.IOException - Thrown if an I/O error occurred.

close

public void close()
           throws java.io.IOException

Close this input stream.

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable

Overrides:

close in class java.io.InputStream

Throws:

java.io.IOException - Thrown if an I/O error occurred.