You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@commons.apache.org by ba...@apache.org on 2002/11/06 20:15:40 UTC
cvs commit: jakarta-commons/lang/src/java/org/apache/commons/lang/functor Executor.java ExecutorException.java ExecutorUtils.java
bayard 2002/11/06 11:15:40
Added: lang/src/java/org/apache/commons/lang/functor Executor.java
ExecutorException.java ExecutorUtils.java
Log:
And a new name. Until it gets changed.
Revision Changes Path
1.1 jakarta-commons/lang/src/java/org/apache/commons/lang/functor/Executor.java
Index: Executor.java
===================================================================
/* ====================================================================
* 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;
/**
* <code>Executor</code> defines an interface implemented by classes that
* 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 $
*/
public interface Executor {
/**
* Does what it has to.
*
* @param description the extra information needed to execute the
* command
*
* @throws ExecutorException (runtime) if the execution fails
*/
public void execute(Object description);
}
1.1 jakarta-commons/lang/src/java/org/apache/commons/lang/functor/ExecutorException.java
Index: ExecutorException.java
===================================================================
/* ====================================================================
* 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);
}
}
1.1 jakarta-commons/lang/src/java/org/apache/commons/lang/functor/ExecutorUtils.java
Index: ExecutorUtils.java
===================================================================
/* ====================================================================
* 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);
}
}
}
}
--
To unsubscribe, e-mail: <ma...@jakarta.apache.org>
For additional commands, e-mail: <ma...@jakarta.apache.org>