com.gemstone.gemfire.cache.execute
Class FunctionAdapter

java.lang.Object
  com.gemstone.gemfire.cache.execute.FunctionAdapter

All Implemented Interfaces:

Function, Serializable

public abstract class FunctionAdapter
extends Object
implements Function

Application developers can extend this class instead of implementing the Function interface.

This implementation provides the following defaults

1. Function.hasResult() returns true
2. Function.optimizeForWrite() returns false
3. Function.isHA() returns true

Since:

6.0

See Also:

Function, Serialized Form

Constructor Summary

FunctionAdapter()

Method Summary

abstract void	execute(FunctionContext context) The method which contains the logic to be executed.
abstract String	getId() Return a unique function identifier, used to register the function with FunctionService
boolean	hasResult() Specifies whether the function sends results while executing.
boolean	isHA() Specifies whether the function is eligible for re-execution (in case of failure).
boolean	optimizeForWrite() Return true to indicate to GemFire the method requires optimization for writing the targeted FunctionService.onRegion(com.gemstone.gemfire.cache.Region) and any associated routing objects .

Methods inherited from class java.lang.Object

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

Constructor Detail

FunctionAdapter

public FunctionAdapter()

Method Detail

execute

public abstract void execute(FunctionContext context)

The method which contains the logic to be executed. This method should be thread safe and may be invoked more than once on a given member for a single Execution. The context provided to this function is the one which was built using Execution. The contexts can be data dependent or data-independent so user should check to see if the context provided in parameter is instance of RegionFunctionContext.

Specified by:

execute in interface Function

Parameters:

context - as created by Execution

Since:

6.0

getId

public abstract String getId()

Return a unique function identifier, used to register the function with FunctionService

Specified by:

getId in interface Function

Returns:

string identifying this function

Since:

6.0

hasResult

public boolean hasResult()

Specifies whether the function sends results while executing. The method returns false if no result is expected.

If Function.hasResult() returns false, ResultCollector.getResult() throws FunctionException.

If Function.hasResult() returns true, ResultCollector.getResult() blocks and waits for the result of function execution

Specified by:

hasResult in interface Function

Returns:

whether this function returns a Result back to the caller.

Since:

6.0

optimizeForWrite

public boolean optimizeForWrite()

Return true to indicate to GemFire the method requires optimization for writing the targeted FunctionService.onRegion(com.gemstone.gemfire.cache.Region) and any associated routing objects .

Returning false will optimize for read behavior on the targeted FunctionService.onRegion(com.gemstone.gemfire.cache.Region) and any associated routing objects .

This method is only consulted when invoked as a data dependent function

Specified by:

optimizeForWrite in interface Function

Returns:

false if the function is read only, otherwise returns true

Since:

6.0

See Also:

FunctionService

isHA

public boolean isHA()

Specifies whether the function is eligible for re-execution (in case of failure).

Specified by:

isHA in interface Function

Returns:

whether the function is eligible for re-execution.

Since:

6.5

See Also:

FunctionContext.isPossibleDuplicate()