And a new name. Until it gets changed.
git-svn-id: https://svn.apache.org/repos/asf/jakarta/commons/proper/lang/trunk@137115 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
parent
27c8d12495
commit
29eb9686b6
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@ -0,0 +1,75 @@
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|||
/* ====================================================================
|
||||
* The Apache Software License, Version 1.1
|
||||
*
|
||||
* Copyright (c) 2002 The Apache Software Foundation. All rights
|
||||
* reserved.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
*
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in
|
||||
* the documentation and/or other materials provided with the
|
||||
* distribution.
|
||||
*
|
||||
* 3. The end-user documentation included with the redistribution, if
|
||||
* any, must include the following acknowlegement:
|
||||
* "This product includes software developed by the
|
||||
* Apache Software Foundation (http://www.apache.org/)."
|
||||
* Alternately, this acknowlegement may appear in the software itself,
|
||||
* if and wherever such third-party acknowlegements normally appear.
|
||||
*
|
||||
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
|
||||
* Foundation" must not be used to endorse or promote products derived
|
||||
* from this software without prior written permission. For written
|
||||
* permission, please contact apache@apache.org.
|
||||
*
|
||||
* 5. Products derived from this software may not be called "Apache"
|
||||
* nor may "Apache" appear in their names without prior written
|
||||
* permission of the Apache Software Foundation.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
|
||||
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||||
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
|
||||
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
|
||||
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
||||
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
||||
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
||||
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
* ====================================================================
|
||||
*
|
||||
* This software consists of voluntary contributions made by many
|
||||
* individuals on behalf of the Apache Software Foundation. For more
|
||||
* information on the Apache Software Foundation, please see
|
||||
* <http://www.apache.org/>.
|
||||
*/
|
||||
package org.apache.commons.lang.functor;
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|
||||
/**
|
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* <code>Executor</code> defines an interface implemented by classes that
|
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* do something.
|
||||
*
|
||||
* @author <a href="mailto:nicolaken@apache.org">Nicola Ken Barozzi</a>
|
||||
* @version $Id: Executor.java,v 1.1 2002/11/06 19:15:40 bayard Exp $
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||||
*/
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||||
public interface Executor {
|
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|
||||
/**
|
||||
* Does what it has to.
|
||||
*
|
||||
* @param description the extra information needed to execute the
|
||||
* command
|
||||
*
|
||||
* @throws ExecutorException (runtime) if the execution fails
|
||||
*/
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public void execute(Object description);
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||||
|
||||
}
|
|
@ -0,0 +1,107 @@
|
|||
/* ====================================================================
|
||||
* The Apache Software License, Version 1.1
|
||||
*
|
||||
* Copyright (c) 2002 The Apache Software Foundation. All rights
|
||||
* reserved.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
*
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in
|
||||
* the documentation and/or other materials provided with the
|
||||
* distribution.
|
||||
*
|
||||
* 3. The end-user documentation included with the redistribution, if
|
||||
* any, must include the following acknowlegement:
|
||||
* "This product includes software developed by the
|
||||
* Apache Software Foundation (http://www.apache.org/)."
|
||||
* Alternately, this acknowlegement may appear in the software itself,
|
||||
* if and wherever such third-party acknowlegements normally appear.
|
||||
*
|
||||
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
|
||||
* Foundation" must not be used to endorse or promote products derived
|
||||
* from this software without prior written permission. For written
|
||||
* permission, please contact apache@apache.org.
|
||||
*
|
||||
* 5. Products derived from this software may not be called "Apache"
|
||||
* nor may "Apache" appear in their names without prior written
|
||||
* permission of the Apache Software Foundation.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
|
||||
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||||
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
|
||||
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
|
||||
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
||||
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
||||
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
||||
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
* ====================================================================
|
||||
*
|
||||
* This software consists of voluntary contributions made by many
|
||||
* individuals on behalf of the Apache Software Foundation. For more
|
||||
* information on the Apache Software Foundation, please see
|
||||
* <http://www.apache.org/>.
|
||||
*/
|
||||
package org.apache.commons.lang.functor;
|
||||
|
||||
import org.apache.commons.lang.exception.NestableRuntimeException;
|
||||
/**
|
||||
* Exception thrown when the Comand fails to execute.
|
||||
* If required, a root cause error can be wrapped within this one.
|
||||
*
|
||||
* @author <a href="mailto:nicolaken@apache.org">Nicola Ken Barozzi</a>
|
||||
* @version $Id: ExecutorException.java,v 1.1 2002/11/06 19:15:40 bayard Exp $
|
||||
*/
|
||||
public class ExecutorException extends NestableRuntimeException {
|
||||
|
||||
/**
|
||||
* Constructs a new <code>ExecutorException</code> without specified
|
||||
* detail message.
|
||||
*/
|
||||
public ExecutorException() {
|
||||
super();
|
||||
}
|
||||
|
||||
/**
|
||||
* Constructs a new <code>ExecutorException</code> with specified
|
||||
* detail message.
|
||||
*
|
||||
* @param msg the error message.
|
||||
*/
|
||||
public ExecutorException(String msg) {
|
||||
super(msg);
|
||||
}
|
||||
|
||||
/**
|
||||
* Constructs a new <code>ExecutorException</code> with specified
|
||||
* nested <code>Throwable</code> root cause.
|
||||
*
|
||||
* @param rootCause the exception or error that caused this exception
|
||||
* to be thrown.
|
||||
*/
|
||||
public ExecutorException(Throwable rootCause) {
|
||||
super(rootCause);
|
||||
}
|
||||
|
||||
/**
|
||||
* Constructs a new <code>ExecutorException</code> with specified
|
||||
* detail message and nested <code>Throwable</code> root cause.
|
||||
*
|
||||
* @param msg the error message.
|
||||
* @param rootCause the exception or error that caused this exception
|
||||
* to be thrown.
|
||||
*/
|
||||
public ExecutorException(String msg, Throwable rootCause) {
|
||||
super(msg, rootCause);
|
||||
}
|
||||
|
||||
}
|
|
@ -0,0 +1,689 @@
|
|||
/* ====================================================================
|
||||
* The Apache Software License, Version 1.1
|
||||
*
|
||||
* Copyright (c) 2002 The Apache Software Foundation. All rights
|
||||
* reserved.
|
||||
*
|
||||
* Redistribution and use in source and binary forms, with or without
|
||||
* modification, are permitted provided that the following conditions
|
||||
* are met:
|
||||
*
|
||||
* 1. Redistributions of source code must retain the above copyright
|
||||
* notice, this list of conditions and the following disclaimer.
|
||||
*
|
||||
* 2. Redistributions in binary form must reproduce the above copyright
|
||||
* notice, this list of conditions and the following disclaimer in
|
||||
* the documentation and/or other materials provided with the
|
||||
* distribution.
|
||||
*
|
||||
* 3. The end-user documentation included with the redistribution, if
|
||||
* any, must include the following acknowlegement:
|
||||
* "This product includes software developed by the
|
||||
* Apache Software Foundation (http://www.apache.org/)."
|
||||
* Alternately, this acknowlegement may appear in the software itself,
|
||||
* if and wherever such third-party acknowlegements normally appear.
|
||||
*
|
||||
* 4. The names "The Jakarta Project", "Commons", and "Apache Software
|
||||
* Foundation" must not be used to endorse or promote products derived
|
||||
* from this software without prior written permission. For written
|
||||
* permission, please contact apache@apache.org.
|
||||
*
|
||||
* 5. Products derived from this software may not be called "Apache"
|
||||
* nor may "Apache" appear in their names without prior written
|
||||
* permission of the Apache Software Foundation.
|
||||
*
|
||||
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
|
||||
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
||||
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
|
||||
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
|
||||
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
||||
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
||||
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
|
||||
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
|
||||
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
||||
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
||||
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||||
* SUCH DAMAGE.
|
||||
* ====================================================================
|
||||
*
|
||||
* This software consists of voluntary contributions made by many
|
||||
* individuals on behalf of the Apache Software Foundation. For more
|
||||
* information on the Apache Software Foundation, please see
|
||||
* <http://www.apache.org/>.
|
||||
*/
|
||||
package org.apache.commons.lang.functor;
|
||||
|
||||
import java.io.Serializable;
|
||||
import java.util.Collection;
|
||||
import java.util.Iterator;
|
||||
import java.util.Map;
|
||||
|
||||
import org.apache.commons.lang.functor.Predicate;
|
||||
import org.apache.commons.lang.functor.PredicateUtils;
|
||||
import org.apache.commons.lang.functor.Transformer;
|
||||
import org.apache.commons.lang.functor.TransformerException;
|
||||
import org.apache.commons.lang.functor.TransformerUtils;
|
||||
/**
|
||||
* <code>ExecutorUtils</code> provides reference implementations and utilities
|
||||
* for the Executor pattern interface. The supplied commands are:
|
||||
* <ul>
|
||||
* <li>Invoker - invokes a method on the input object
|
||||
* <li>For - repeatedly calls a command for a fixed number of times
|
||||
* <li>While - repeatedly calls a command while a predicate is true
|
||||
* <li>DoWhile - repeatedly calls a command while a predicate is true
|
||||
* <li>Chained - chains two or more commands together
|
||||
* <li>Switch - calls one command based on one or more predicates
|
||||
* <li>SwitchMap - calls one command looked up from a Map
|
||||
* <li>Transformer - wraps a Transformer as a Predicate
|
||||
* <li>NOP - does nothing
|
||||
* <li>Exception - always throws an exception
|
||||
* </ul>
|
||||
* All the supplied commands are Serializable.
|
||||
*
|
||||
* @author <a href="mailto:scolebourne@joda.org">Stephen Colebourne</a>
|
||||
* @version $Id: ExecutorUtils.java,v 1.1 2002/11/06 19:15:40 bayard Exp $
|
||||
*/
|
||||
public class ExecutorUtils {
|
||||
|
||||
/**
|
||||
* A Executor that always throws an exception
|
||||
*/
|
||||
private static final Executor EXCEPTION_COMMAND = new ExceptionExecutor();
|
||||
/**
|
||||
* A Executor that does nothing
|
||||
*/
|
||||
private static final Executor NOP_COMMAND = new NOPExecutor();
|
||||
|
||||
/**
|
||||
* Restrictive constructor
|
||||
*/
|
||||
protected ExecutorUtils() {
|
||||
super();
|
||||
}
|
||||
|
||||
/**
|
||||
* Gets a Executor that always throws an exception.
|
||||
* This could be useful during testing as a placeholder.
|
||||
*
|
||||
* @return the command
|
||||
*/
|
||||
public static Executor exceptionExecutor() {
|
||||
return EXCEPTION_COMMAND;
|
||||
}
|
||||
|
||||
/**
|
||||
* Gets a Executor that will do nothing.
|
||||
* This could be useful during testing as a placeholder.
|
||||
*
|
||||
* @return the command
|
||||
*/
|
||||
public static Executor nopExecutor() {
|
||||
return NOP_COMMAND;
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a Executor that calls a Factory each time the transformer is used.
|
||||
* The transformer will return the value returned by the factory.
|
||||
*
|
||||
* @param transformer the transformer to run each time in the command
|
||||
* @return the command.
|
||||
*/
|
||||
public static Executor asExecutor(Transformer transformer) {
|
||||
if (transformer == null) {
|
||||
throw new IllegalArgumentException("TransformerExecutor: The transformer must not be null");
|
||||
}
|
||||
return new TransformerExecutor(transformer);
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a Executor that will call the command <code>count</code> times.
|
||||
*
|
||||
* @param count the number of times to loop
|
||||
* @param command the command to call repeatedly
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if either argument is null
|
||||
*/
|
||||
public static Executor forExecutor(int count, Executor command) {
|
||||
if (count < 0) {
|
||||
throw new IllegalArgumentException("ForExecutor: The loop count must not be less than zero, it was " + count);
|
||||
}
|
||||
if (command == null) {
|
||||
throw new IllegalArgumentException("ForExecutor: The command must not be null");
|
||||
}
|
||||
return new ForExecutor(count, command);
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a Executor that will call the command repeatedly until the
|
||||
* predicate returns false.
|
||||
*
|
||||
* @param predicate the predicate to use as an end of loop test
|
||||
* @param command the command to call repeatedly
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if either argument is null
|
||||
*/
|
||||
public static Executor whileExecutor(Predicate predicate, Executor command) {
|
||||
if (predicate == null) {
|
||||
throw new IllegalArgumentException("WhileExecutor: The predicate must not be null");
|
||||
}
|
||||
if (command == null) {
|
||||
throw new IllegalArgumentException("WhileExecutor: The command must not be null");
|
||||
}
|
||||
return new WhileExecutor(predicate, command, false);
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a Executor that will call the command once and then repeatedly
|
||||
* until the predicate returns false.
|
||||
*
|
||||
* @param command the command to call repeatedly
|
||||
* @param predicate the predicate to use as an end of loop test
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if either argument is null
|
||||
*/
|
||||
public static Executor doWhileExecutor(Executor command, Predicate predicate) {
|
||||
if (command == null) {
|
||||
throw new IllegalArgumentException("DoWhileExecutor: The command must not be null");
|
||||
}
|
||||
if (predicate == null) {
|
||||
throw new IllegalArgumentException("DoWhileExecutor: The predicate must not be null");
|
||||
}
|
||||
return new WhileExecutor(predicate, command, true);
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a Executor that will invoke a specific method on the command's
|
||||
* input object by reflection.
|
||||
*
|
||||
* @param methodName the name of the method
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if the method name is null
|
||||
*/
|
||||
public static Executor invokerExecutor(String methodName) {
|
||||
return asExecutor(TransformerUtils.invokerTransformer(methodName, null, null));
|
||||
}
|
||||
|
||||
/**
|
||||
* Creates a Executor that will invoke a specific method on the command's
|
||||
* input object by reflection.
|
||||
*
|
||||
* @param methodName the name of the method
|
||||
* @param paramTypes the parameter types
|
||||
* @param args the arguments
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if the method name is null
|
||||
* @throws IllegalArgumentException if the paramTypes and args don't match
|
||||
*/
|
||||
public static Executor invokerExecutor(String methodName, Class[] paramTypes, Object[] args) {
|
||||
return asExecutor(TransformerUtils.invokerTransformer(methodName, paramTypes, args));
|
||||
}
|
||||
|
||||
/**
|
||||
* Create a new Executor that calls two Executors, passing the result of
|
||||
* the first into the second.
|
||||
*
|
||||
* @param command1 the first command
|
||||
* @param command2 the second command
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if either command is null
|
||||
*/
|
||||
public static Executor chainedExecutor(Executor command1, Executor command2) {
|
||||
Executor[] commands = new Executor[] { command1, command2 };
|
||||
validate(commands);
|
||||
return new ChainedExecutor(commands);
|
||||
}
|
||||
|
||||
/**
|
||||
* Create a new Executor that calls each command in turn, passing the
|
||||
* result into the next command.
|
||||
*
|
||||
* @param commands an array of commands to chain
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if the commands array is null
|
||||
* @throws IllegalArgumentException if the commands array has 0 elements
|
||||
* @throws IllegalArgumentException if any command in the array is null
|
||||
*/
|
||||
public static Executor chainedExecutor(Executor[] commands) {
|
||||
commands = copy(commands);
|
||||
validate(commands);
|
||||
return new ChainedExecutor(commands);
|
||||
}
|
||||
|
||||
/**
|
||||
* Create a new Executor that calls each command in turn, passing the
|
||||
* result into the next command. The ordering is that of the iterator()
|
||||
* method on the collection.
|
||||
*
|
||||
* @param commands a collection of commands to chain
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if the commands collection is null
|
||||
* @throws IllegalArgumentException if the commands collection is empty
|
||||
* @throws IllegalArgumentException if any command in the collection is null
|
||||
*/
|
||||
public static Executor chainedExecutor(Collection commands) {
|
||||
if (commands == null) {
|
||||
throw new IllegalArgumentException("ChainedExecutor: The command collection must not be null");
|
||||
}
|
||||
// convert to array like this to guarantee iterator() ordering
|
||||
Executor[] cmds = new Executor[commands.size()];
|
||||
int i = 0;
|
||||
for (Iterator it = commands.iterator(); it.hasNext();) {
|
||||
cmds[i++] = (Executor) it.next();
|
||||
}
|
||||
validate(cmds);
|
||||
return new ChainedExecutor(cmds);
|
||||
}
|
||||
|
||||
/**
|
||||
* Create a new Executor that calls one of two commands depending
|
||||
* on the specified predicate.
|
||||
*
|
||||
* @param predicate the predicate to switch on
|
||||
* @param trueExecutor the command called if the predicate is true
|
||||
* @param falseExecutor the command called if the predicate is false
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if the predicate is null
|
||||
* @throws IllegalArgumentException if either command is null
|
||||
*/
|
||||
public static Executor switchExecutor(Predicate predicate, Executor trueExecutor, Executor falseExecutor) {
|
||||
return switchExecutorInternal(new Predicate[] { predicate }, new Executor[] { trueExecutor }, falseExecutor);
|
||||
}
|
||||
|
||||
/**
|
||||
* Create a new Executor that calls one of the commands depending
|
||||
* on the predicates. The command at array location 0 is called if the
|
||||
* predicate at array location 0 returned true. Each predicate is evaluated
|
||||
* until one returns true.
|
||||
*
|
||||
* @param predicates an array of predicates to check
|
||||
* @param commands an array of commands to call
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if the either array is null
|
||||
* @throws IllegalArgumentException if the either array has 0 elements
|
||||
* @throws IllegalArgumentException if any element in the arrays is null
|
||||
* @throws IllegalArgumentException if the arrays are different sizes
|
||||
*/
|
||||
public static Executor switchExecutor(Predicate[] predicates, Executor[] commands) {
|
||||
return switchExecutorInternal(copy(predicates), copy(commands), null);
|
||||
}
|
||||
|
||||
/**
|
||||
* Create a new Executor that calls one of the commands depending
|
||||
* on the predicates. The command at array location 0 is called if the
|
||||
* predicate at array location 0 returned true. Each predicate is evaluated
|
||||
* until one returns true. If no predicates evaluate to true, the default
|
||||
* command is called.
|
||||
*
|
||||
* @param predicates an array of predicates to check
|
||||
* @param commands an array of commands to call
|
||||
* @param defaultExecutor the default to call if no predicate matches
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if the either array is null
|
||||
* @throws IllegalArgumentException if the either array has 0 elements
|
||||
* @throws IllegalArgumentException if any element in the arrays is null
|
||||
* @throws IllegalArgumentException if the arrays are different sizes
|
||||
*/
|
||||
public static Executor switchExecutor(Predicate[] predicates, Executor[] commands, Executor defaultExecutor) {
|
||||
return switchExecutorInternal(copy(predicates), copy(commands), defaultExecutor);
|
||||
}
|
||||
|
||||
/**
|
||||
* Create a new Executor that calls one of the commands depending
|
||||
* on the predicates.
|
||||
* <p>
|
||||
* The Map consists of Predicate keys and Executor values. A command
|
||||
* is called if its matching predicate returns true. Each predicate is evaluated
|
||||
* until one returns true. If no predicates evaluate to true, the default
|
||||
* command is called. The default command is set in the map with a
|
||||
* null key. The ordering is that of the iterator() method on the entryset
|
||||
* collection of the map.
|
||||
*
|
||||
* @param predicatesAndExecutors a map of predicates to commands
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if the map is null
|
||||
* @throws IllegalArgumentException if the map is empty
|
||||
* @throws IllegalArgumentException if any command in the map is null
|
||||
* @throws ClassCastException if the map elements are of the wrong type
|
||||
*/
|
||||
public static Executor switchExecutor(Map predicatesAndExecutors) {
|
||||
Executor[] trs = null;
|
||||
Predicate[] preds = null;
|
||||
if (predicatesAndExecutors == null) {
|
||||
throw new IllegalArgumentException("SwitchExecutor: The predicate and command map must not be null");
|
||||
}
|
||||
// convert to array like this to guarantee iterator() ordering
|
||||
Executor def = (Executor) predicatesAndExecutors.remove(null);
|
||||
int size = predicatesAndExecutors.size();
|
||||
trs = new Executor[size];
|
||||
preds = new Predicate[size];
|
||||
int i = 0;
|
||||
for (Iterator it = predicatesAndExecutors.entrySet().iterator(); it.hasNext();) {
|
||||
Map.Entry entry = (Map.Entry) it.next();
|
||||
preds[i] = (Predicate) entry.getKey();
|
||||
trs[i] = (Executor) entry.getValue();
|
||||
i++;
|
||||
}
|
||||
return switchExecutorInternal(preds, trs, def);
|
||||
}
|
||||
|
||||
/**
|
||||
* Validate input and create command
|
||||
*/
|
||||
private static Executor switchExecutorInternal(Predicate[] predicates, Executor[] commands, Executor defaultExecutor) {
|
||||
validate(predicates);
|
||||
validate(commands);
|
||||
if (predicates.length != commands.length) {
|
||||
throw new IllegalArgumentException("SwitchExecutor: The predicate and command arrays must be the same size");
|
||||
}
|
||||
if (defaultExecutor == null) {
|
||||
defaultExecutor = nopExecutor();
|
||||
}
|
||||
return new SwitchExecutor(predicates, commands, defaultExecutor);
|
||||
}
|
||||
|
||||
/**
|
||||
* Create a new Executor that uses the input object as a key to find the
|
||||
* command to call.
|
||||
* <p>
|
||||
* The Map consists of object keys and Executor values. A command
|
||||
* is called if the input object equals the key. If there is no match, the
|
||||
* default command is called. The default command is set in the map
|
||||
* using a null key.
|
||||
*
|
||||
* @param objectsAndExecutors a map of objects to commands
|
||||
* @return the command
|
||||
* @throws IllegalArgumentException if the map is null
|
||||
* @throws IllegalArgumentException if the map is empty
|
||||
* @throws IllegalArgumentException if any command in the map is null
|
||||
*/
|
||||
public static Executor switchMapExecutor(Map objectsAndExecutors) {
|
||||
Executor[] trs = null;
|
||||
Predicate[] preds = null;
|
||||
if (objectsAndExecutors == null) {
|
||||
throw new IllegalArgumentException("SwitchEqualsExecutor: The obejct and command map must not be null");
|
||||
}
|
||||
Executor def = (Executor) objectsAndExecutors.remove(null);
|
||||
int size = objectsAndExecutors.size();
|
||||
trs = new Executor[size];
|
||||
preds = new Predicate[size];
|
||||
int i = 0;
|
||||
for (Iterator it = objectsAndExecutors.entrySet().iterator(); it.hasNext();) {
|
||||
Map.Entry entry = (Map.Entry) it.next();
|
||||
preds[i] = PredicateUtils.equalPredicate(entry.getKey());
|
||||
trs[i] = (Executor) entry.getValue();
|
||||
i++;
|
||||
}
|
||||
return switchExecutor(preds, trs, def);
|
||||
}
|
||||
|
||||
/**
|
||||
* Copy method
|
||||
*
|
||||
* @param predicates the predicates to copy
|
||||
*/
|
||||
private static Predicate[] copy(Predicate[] predicates) {
|
||||
if (predicates == null) {
|
||||
return null;
|
||||
}
|
||||
return (Predicate[]) predicates.clone();
|
||||
}
|
||||
|
||||
/**
|
||||
* Validate method
|
||||
*
|
||||
* @param predicates the predicates to validate
|
||||
*/
|
||||
private static void validate(Predicate[] predicates) {
|
||||
if (predicates == null) {
|
||||
throw new IllegalArgumentException("ExecutorUtils: The predicate array must not be null");
|
||||
}
|
||||
if (predicates.length < 1) {
|
||||
throw new IllegalArgumentException(
|
||||
"ExecutorUtils: At least 1 predicate must be specified in the predicate array, size was " + predicates.length);
|
||||
}
|
||||
for (int i = 0; i < predicates.length; i++) {
|
||||
if (predicates[i] == null) {
|
||||
throw new IllegalArgumentException("ExecutorUtils: The predicate array must not contain a null predicate, index " + i + " was null");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Copy method
|
||||
*
|
||||
* @param commands the commands to copy
|
||||
*/
|
||||
private static Executor[] copy(Executor[] commands) {
|
||||
if (commands == null) {
|
||||
return null;
|
||||
}
|
||||
return (Executor[]) commands.clone();
|
||||
}
|
||||
|
||||
/**
|
||||
* Validate method
|
||||
*
|
||||
* @param commands the commands to validate
|
||||
*/
|
||||
private static void validate(Executor[] commands) {
|
||||
if (commands == null) {
|
||||
throw new IllegalArgumentException("ExecutorUtils: The command array must not be null");
|
||||
}
|
||||
if (commands.length < 1) {
|
||||
throw new IllegalArgumentException(
|
||||
"ExecutorUtils: At least 1 command must be specified in the command array, size was " + commands.length);
|
||||
}
|
||||
for (int i = 0; i < commands.length; i++) {
|
||||
if (commands[i] == null) {
|
||||
throw new IllegalArgumentException("ExecutorUtils: The command array must not contain a null command, index " + i + " was null");
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// ExceptionExecutor
|
||||
//----------------------------------------------------------------------------------
|
||||
|
||||
/**
|
||||
* ExceptionExecutor always throws an exception
|
||||
*/
|
||||
private static class ExceptionExecutor implements Executor, Serializable {
|
||||
|
||||
/**
|
||||
* Constructor
|
||||
*/
|
||||
private ExceptionExecutor() {
|
||||
super();
|
||||
}
|
||||
|
||||
/**
|
||||
* Always throw an exception
|
||||
*/
|
||||
public void execute(Object input) {
|
||||
throw new ExecutorException("ExceptionExecutor invoked");
|
||||
}
|
||||
}
|
||||
|
||||
// NOPExecutor
|
||||
//----------------------------------------------------------------------------------
|
||||
|
||||
/**
|
||||
* NOPExecutor does nothing
|
||||
*/
|
||||
private static class NOPExecutor implements Executor, Serializable {
|
||||
|
||||
/**
|
||||
* Constructor
|
||||
*/
|
||||
private NOPExecutor() {
|
||||
super();
|
||||
}
|
||||
|
||||
/**
|
||||
* Do nothing
|
||||
*/
|
||||
public void execute(Object input) {
|
||||
// do nothing
|
||||
}
|
||||
}
|
||||
|
||||
// TransformerExecutor
|
||||
//----------------------------------------------------------------------------------
|
||||
|
||||
/**
|
||||
* TransformerExecutor returns the result of calling a Transformer.
|
||||
*/
|
||||
private static class TransformerExecutor implements Executor, Serializable {
|
||||
|
||||
private final Transformer iTransformer;
|
||||
|
||||
/**
|
||||
* Constructor to store factory
|
||||
*/
|
||||
private TransformerExecutor(Transformer transformer) {
|
||||
super();
|
||||
iTransformer = transformer;
|
||||
}
|
||||
|
||||
/**
|
||||
* Return the result of calling the factory
|
||||
*/
|
||||
public void execute(Object input) {
|
||||
try {
|
||||
iTransformer.transform(input);
|
||||
|
||||
} catch (TransformerException ex) {
|
||||
throw new ExecutorException("TransformerExecutor: " + ex.getMessage(), ex);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// ChainedExecutor
|
||||
//----------------------------------------------------------------------------------
|
||||
|
||||
/**
|
||||
* ChainedExecutor calls a list of commands.
|
||||
*/
|
||||
private static class ChainedExecutor implements Executor, Serializable {
|
||||
|
||||
private final Executor[] iExecutors;
|
||||
|
||||
/**
|
||||
* Constructor to store params
|
||||
*/
|
||||
private ChainedExecutor(Executor[] commands) {
|
||||
super();
|
||||
iExecutors = commands;
|
||||
}
|
||||
|
||||
/**
|
||||
* Execute a list of commands
|
||||
*/
|
||||
public void execute(Object input) {
|
||||
for (int i = 0; i < iExecutors.length; i++) {
|
||||
iExecutors[i].execute(input);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// SwitchExecutor
|
||||
//----------------------------------------------------------------------------------
|
||||
|
||||
/**
|
||||
* SwitchExecutor calls the command whose predicate returns true.
|
||||
*/
|
||||
private static class SwitchExecutor implements Executor, Serializable {
|
||||
|
||||
private final Predicate[] iPredicates;
|
||||
private final Executor[] iExecutors;
|
||||
private final Executor iDefault;
|
||||
|
||||
/**
|
||||
* Constructor to store params
|
||||
*/
|
||||
private SwitchExecutor(Predicate[] predicates, Executor[] commands, Executor defaultExecutor) {
|
||||
super();
|
||||
iPredicates = predicates;
|
||||
iExecutors = commands;
|
||||
iDefault = defaultExecutor;
|
||||
}
|
||||
|
||||
/**
|
||||
* Execute the command whose predicate returns true
|
||||
*/
|
||||
public void execute(Object input) {
|
||||
for (int i = 0; i < iPredicates.length; i++) {
|
||||
if (iPredicates[i].evaluate(input) == true) {
|
||||
iExecutors[i].execute(input);
|
||||
return;
|
||||
}
|
||||
}
|
||||
iDefault.execute(input);
|
||||
}
|
||||
}
|
||||
|
||||
// ForExecutor
|
||||
//----------------------------------------------------------------------------------
|
||||
|
||||
/**
|
||||
* ForExecutor calls the command a fixed nunmber of times.
|
||||
*/
|
||||
private static class ForExecutor implements Executor, Serializable {
|
||||
|
||||
private final int iCount;
|
||||
private final Executor iExecutor;
|
||||
|
||||
/**
|
||||
* Constructor to store params
|
||||
*/
|
||||
private ForExecutor(int count, Executor command) {
|
||||
super();
|
||||
iCount = count;
|
||||
iExecutor = command;
|
||||
}
|
||||
|
||||
/**
|
||||
* Execute the command count times
|
||||
*/
|
||||
public void execute(Object input) {
|
||||
for (int i = 0; i < iCount; i++) {
|
||||
iExecutor.execute(input);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
// WhileExecutor
|
||||
//----------------------------------------------------------------------------------
|
||||
|
||||
/**
|
||||
* WhileExecutor calls the command until the predicate is false.
|
||||
*/
|
||||
private static class WhileExecutor implements Executor, Serializable {
|
||||
|
||||
private final Predicate iPredicate;
|
||||
private final Executor iExecutor;
|
||||
private final boolean iDoLoop;
|
||||
|
||||
/**
|
||||
* Constructor to store params
|
||||
*/
|
||||
private WhileExecutor(Predicate predicate, Executor command, boolean doLoop) {
|
||||
super();
|
||||
iPredicate = predicate;
|
||||
iExecutor = command;
|
||||
iDoLoop = doLoop;
|
||||
}
|
||||
|
||||
/**
|
||||
* Execute the command until the predicate is false
|
||||
*/
|
||||
public void execute(Object input) {
|
||||
if (iDoLoop) {
|
||||
iExecutor.execute(input);
|
||||
}
|
||||
while (iPredicate.evaluate(input)) {
|
||||
iExecutor.execute(input);
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
}
|
Loading…
Reference in New Issue