dk.rode.thesis.command
Class CommandProcessingResult<E>

java.lang.Object
  dk.rode.thesis.command.CommandProcessingResult<E>

Type Parameters:

E - The type of result obtained from the executed commands.

public class CommandProcessingResult<E>
extends Object

A command processing result represents the result of executing a list commands by a given command processor.

The result can represent two scenarios:

1. The execution succeeded: executed is true, and result stores the value, which may be null. The result is the command value fetched from the last - possibly spawned - command executed.

2. The execution failed, but was able to be completely undone: executed is false, and result is always null.

In case the execution and undo fails completely, the processor will throw an exception, and not return a result.

Author:

Gunni Rode / rode.dk

See Also:

CommandProcessor.execute(List), Command.getResult()

Field Summary

boolean	executed True if the commands that generated this result were successfully executed, and hence the value of result is known to be valid.
E	result The result of the command execution.

Constructor Summary

CommandProcessingResult(boolean executed, E result)
Constructor.

Method Summary

String

toString() Returns the string representation of this result.

Methods inherited from class java.lang.Object

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

Field Detail

executed

public final boolean executed

True if the commands that generated this result were successfully executed, and hence the value of result is known to be valid.

If false, the execution failed, but all commands were successfully undone. The value of result will always be null in such cases.

result

public final E result

The result of the command execution.

The value is the result value from the last - possibly spawned - command executed.

Can be null, even if executed is true.

Constructor Detail

CommandProcessingResult

CommandProcessingResult(boolean executed,
                        E result)

Constructor.

Parameters:

executed - The executed flag.

result - The result of the execution; can be null.

Method Detail

toString

public String toString()

Returns the string representation of this result.

Overrides:

toString in class Object

Returns:

The string representation; never null.