Package edu.rit.mp.buf

Class SharedDoubleArrayBuf_1

java.lang.Object

edu.rit.mp.Buf

edu.rit.mp.DoubleBuf

edu.rit.mp.buf.SharedDoubleArrayBuf

edu.rit.mp.buf.SharedDoubleArrayBuf_1

public class SharedDoubleArrayBuf_1
extends SharedDoubleArrayBuf

Class SharedDoubleArrayBuf_1 provides a buffer for a multiple thread safe array of double items sent or received using the Message Protocol (MP). The array element stride must be 1. While an instance of class SharedDoubleArrayBuf_1 may be constructed directly, normally you will use a factory method in class DoubleBuf. See that class for further information.

Version:

26-Oct-2007

Author:

Alan Kaminsky

Field Summary

Fields inherited from class edu.rit.mp.Buf

myLength

Constructor Summary

Constructors

Constructor	Description
SharedDoubleArrayBuf_1(SharedDoubleArray theArray, Range theRange)	Construct a new shared double array buffer.

Method Summary

Modifier and Type	Method	Description
double	get(int i)	Obtain the given item from this buffer.
Buf	getReductionBuf(Op op)	Create a buffer for performing parallel reduction using the given binary operation.
void	put(int i, double item)	Store the given item in this buffer.
protected int	receiveItems(int i, int num, ByteBuffer buffer)	Receive as many items as possible from the given byte buffer to this buffer.
protected int	sendItems(int i, ByteBuffer buffer)	Send as many items as possible from this buffer to the given byte buffer.

Methods inherited from class edu.rit.mp.DoubleBuf

buffer, buffer, buffer, buffer, buffer, buffer, colSliceBuffer, colSliceBuffers, copy, defaultCopy, emptyBuffer, fill, getTemporaryBuf, patchBuffer, patchBuffers, rowSliceBuffer, rowSliceBuffers, sliceBuffer, sliceBuffer, sliceBuffers, sliceBuffers

Methods inherited from class edu.rit.mp.Buf

length

Methods inherited from class java.lang.Object

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

Constructor Details

SharedDoubleArrayBuf_1

public SharedDoubleArrayBuf_1(SharedDoubleArray theArray,
 Range theRange)

Construct a new shared double array buffer.

Parameters:

theArray - Shared array.

theRange - Range of array elements to include in the buffer. The stride is assumed to be 1.

Method Details

get

public double get(int i)

Obtain the given item from this buffer.

The get() method must not block the calling thread; if it does, all message I/O in MP will be blocked. Obtain the given item from this buffer.

The get() method must not block the calling thread; if it does, all message I/O in MP will be blocked. Obtain the given item from this buffer.

The get() method must not block the calling thread; if it does, all message I/O in MP will be blocked.

Overrides:

get in class SharedDoubleArrayBuf

Parameters:

i - Item index in the range 0 .. length()-1.

Returns:

Item at index i.

put

public void put(int i,
 double item)

Store the given item in this buffer.

The put() method must not block the calling thread; if it does, all message I/O in MP will be blocked. Store the given item in this buffer.

The put() method must not block the calling thread; if it does, all message I/O in MP will be blocked. Store the given item in this buffer.

The put() method must not block the calling thread; if it does, all message I/O in MP will be blocked.

Overrides:

put in class SharedDoubleArrayBuf

Parameters:

i - Item index in the range 0 .. length()-1.

item - Item to be stored at index i.

getReductionBuf

public Buf getReductionBuf(Op op)

Create a buffer for performing parallel reduction using the given binary operation. The results of the reduction are placed into this buffer.

Operations performed on the returned reduction buffer have the same effect as operations performed on this buffer, except whenever a source item S is put into a destination item D in this buffer, D is set to D op S, that is, the reduction of D and S using the given binary operation (rather than just setting D to S). Create a buffer for performing parallel reduction using the given binary operation. The results of the reduction are placed into this buffer. Create a buffer for performing parallel reduction using the given binary operation. The results of the reduction are placed into this buffer.

Overrides:

getReductionBuf in class SharedDoubleArrayBuf

Parameters:

op - Binary operation.

Returns:

a Buf object.

Throws:

ClassCastException - (unchecked exception) Thrown if this buffer's element data type and the given binary operation's argument data type are not the same.

sendItems

protected int sendItems(int i,
 ByteBuffer buffer)

Send as many items as possible from this buffer to the given byte buffer.

The sendItems() method must not block the calling thread; if it does, all message I/O in MP will be blocked. Send as many items as possible from this buffer to the given byte buffer.

The sendItems() method must not block the calling thread; if it does, all message I/O in MP will be blocked. Send as many items as possible from this buffer to the given byte buffer.

The sendItems() method must not block the calling thread; if it does, all message I/O in MP will be blocked.

Overrides:

sendItems in class SharedDoubleArrayBuf

Parameters:

i - Index of first item to send, in the range 0 .. length-1.

buffer - Byte buffer.

Returns:

Number of items sent.

receiveItems

protected int receiveItems(int i,
 int num,
 ByteBuffer buffer)

Receive as many items as possible from the given byte buffer to this buffer.

The receiveItems() method must not block the calling thread; if it does, all message I/O in MP will be blocked. Receive as many items as possible from the given byte buffer to this buffer.

The receiveItems() method must not block the calling thread; if it does, all message I/O in MP will be blocked. Receive as many items as possible from the given byte buffer to this buffer.

The receiveItems() method must not block the calling thread; if it does, all message I/O in MP will be blocked.

Overrides:

receiveItems in class SharedDoubleArrayBuf

Parameters:

i - Index of first item to receive, in the range 0 .. length-1.

num - Maximum number of items to receive.

buffer - Byte buffer.

Returns:

Number of items received.