gr.uoa.di.madgik.searchlibrary.operatorlibrary.gmerge
Class GradualMergeOp

java.lang.Object
  gr.uoa.di.madgik.searchlibrary.operatorlibrary.Unary
      gr.uoa.di.madgik.searchlibrary.operatorlibrary.gmerge.GradualMergeOp

public class GradualMergeOp
extends Unary

Operator class used to create a merged ResultSet output from the contents of multiple ResultSet.

Author:

john.gerbesiotis - DI NKUA

Field Summary

static int	BufferCapacityDef The default capacity of the RecordWriters and, if applicable, of all IRecordReaders' buffers
static OperationMode	OperationModeDef The default operation mode.

Fields inherited from class gr.uoa.di.madgik.searchlibrary.operatorlibrary.Unary

inLocator, operatorParameters, stats, timeout, TimeoutDef, timeUnit, TimeUnitDef

Constructor Summary

GradualMergeOp(URI inLocator, Map<String,String> operatorParameters, long timeout, TimeUnit timeUnit, StatsContainer stats)
Creates a new GradualMergeOp with configurable operation mode and timeout

GradualMergeOp(URI inLocator, Map<String,String> operatorParameters, StatsContainer stats)
Creates a new GradualMergeOp with the default timeout used both for readers and the writer

Method Summary

URI	compute() Performs the merging operation

Methods inherited from class java.lang.Object

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

Field Detail

OperationModeDef

public static final OperationMode OperationModeDef

The default operation mode. Currently set to OperationMode.FirstAvailable

BufferCapacityDef

public static final int BufferCapacityDef

The default capacity of the RecordWriters and, if applicable, of all IRecordReaders' buffers

See Also:

Constant Field Values

Constructor Detail

GradualMergeOp

public GradualMergeOp(URI inLocator,
                      Map<String,String> operatorParameters,
                      StatsContainer stats)
               throws Exception

Creates a new GradualMergeOp with the default timeout used both for readers and the writer

Parameters:

inLocator - The locator of the inputs that will be merged

operatorParameters - oeprator parameters

stats - Statistics

Throws:

Exception

GradualMergeOp

public GradualMergeOp(URI inLocator,
                      Map<String,String> operatorParameters,
                      long timeout,
                      TimeUnit timeUnit,
                      StatsContainer stats)
               throws Exception

Creates a new GradualMergeOp with configurable operation mode and timeout

Parameters:

inLocator - The locator of the inputs that will be merged

operatorParameters - operator parameters

timeout - The timeout that will be used by the RecordWriter and all ForwardReaders

timeUnit - The timeout unit that will be used by the RecordWriter and all ForwardReaders

stats - Statistics

Throws:

Exception

Method Detail

compute

public URI compute()
            throws Exception

Performs the merging operation

Specified by:

compute in class Unary

Returns:

The locator of the merged result set

Throws:

Exception - An unrecoverable for the operation error occurred