Package org.apache.commons.chain.impl

Class ChainBase<C extends Context>

java.lang.Object

org.apache.commons.chain.impl.ChainBase<C>

Type Parameters:

C - Type of the context associated with this chain

All Implemented Interfaces:

Chain<C>, Command<C>

public class ChainBase<C extends Context>
extends Object
implements Chain<C>

Convenience base class for Chain implementations.

Version:

$Revision$ $Date$

Author:

Craig R. McClanahan

Field Summary

Fields inherited from interface org.apache.commons.chain.Command

CONTINUE_PROCESSING, PROCESSING_COMPLETE

Constructor Summary

Constructors

Constructor	Description
ChainBase()	Construct a Chain with no configured Commands.
ChainBase(Collection<Command<C>> commands)	Construct a Chain configured with the specified Commands.
ChainBase(Command<C> command)	Construct a Chain configured with the specified Command.
ChainBase(Command<C>[] commands)	Construct a Chain configured with the specified Commands.

Method Summary

Modifier and Type	Method	Description
<CMD extends Command<C>> void	addCommand(CMD command)	See the Chain JavaDoc.
boolean	execute(C context)	See the Chain JavaDoc.
boolean	isFrozen()	Returns true, if the configuration of our commands list has been frozen by a call to the execute() method, false otherwise.

Methods inherited from class java.lang.Object

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

Constructor Details

ChainBase

public ChainBase()

Construct a Chain with no configured Commands.

ChainBase

public ChainBase(Command<C> command)

Construct a Chain configured with the specified Command.

Parameters:

command - The Command to be configured

Throws:

IllegalArgumentException - if command is null

ChainBase

public ChainBase(Command<C>[] commands)

Construct a Chain configured with the specified Commands.

Parameters:

commands - The Commands to be configured

Throws:

IllegalArgumentException - if commands, or one of the individual Command elements, is null

ChainBase

public ChainBase(Collection<Command<C>> commands)

Construct a Chain configured with the specified Commands.

Parameters:

commands - The Commands to be configured

Throws:

IllegalArgumentException - if commands, or one of the individual Command elements, is null

Method Details

addCommand

public <CMD extends Command<C>> void addCommand(CMD command)

See the Chain JavaDoc.

Specified by:

addCommand in interface Chain<C extends Context>

Type Parameters:

CMD - the Command type to be added in the Chain

Parameters:

command - The Command to be added

Throws:

IllegalArgumentException - if command is null

IllegalStateException - if no further configuration is allowed

execute

public boolean execute(C context)
                throws Exception

See the Chain JavaDoc.

Specified by:

execute in interface Chain<C extends Context>

Specified by:

execute in interface Command<C extends Context>

Parameters:

context - The Context to be processed by this Chain

Returns:

true if the processing of this Context has been completed, or false if the processing of this Context should be delegated to a subsequent Command in an enclosing Chain

Throws:

Exception - if thrown by one of the Commands in this Chain but not handled by a postprocess() method of a Filter

IllegalArgumentException - if context is null

isFrozen

public boolean isFrozen()

Returns true, if the configuration of our commands list has been frozen by a call to the execute() method, false otherwise.

Returns:

true, if the configuration of our commands list has been frozen by a call to the execute() method, false otherwise.

Since:

1.3