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PatternTesting Runtime (patterntesting-rt) is the runtime component for
the PatternTesting framework. It provides the annotations and base classes
for the PatternTesting testing framework (e.g. patterntesting-check,
patterntesting-concurrent or patterntesting-exception) but can be also
used standalone for classpath monitoring or profiling.
It uses AOP and AspectJ to perform this feat.
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/*
* $Id: ReflectionHelper.java,v 1.7 2009/12/19 22:34:09 oboehm Exp $
*
* Copyright (c) 2009 by Oliver Boehm
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express orimplied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* (c)reated 09.03.2009 by oliver ([email protected])
*/
package patterntesting.runtime.util;
import java.lang.reflect.*;
import java.util.*;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.impl.LogFactoryImpl;
/**
* This class is a helper class to access some fields via reflection. Normally
* you should avoid reflection. Handle with care if you use it.
*
* @author oliver
* @since 09.03.2009
* @version $Revision: 1.7 $
*/
public class ReflectionHelper {
private static final Log log = LogFactoryImpl.getLog(ReflectionHelper.class);
/**
* Tries to get the wanted field. Before it is returned the acc
*
* @param cl the cl
* @param name the name
*
* @return the wanted field
*
* @throws NoSuchFieldException the no such field exception
*/
public static Field getField(Class cl, String name)
throws NoSuchFieldException {
try {
Field field = cl.getDeclaredField(name);
field.setAccessible(true);
return field;
} catch (NoSuchFieldException e) {
Class superclass = cl.getSuperclass();
if (superclass == null) {
throw e;
} else {
if (log.isTraceEnabled()) {
log.trace("using " + superclass + " to get " + cl.getName()
+ "." + name + "...");
}
return ReflectionHelper.getField(superclass, name);
}
}
}
/**
* If it can it returns the value of the given field. If not it throws an
* exception.
*
* @param obj the obj
* @param name the name
*
* @return the field value
*
* @throws NoSuchFieldException the no such field exception
* @throws IllegalAccessException the illegal access exception
* @throws IllegalArgumentException the illegal argument exception
*/
public static Object getFieldValue(Object obj, String name)
throws NoSuchFieldException, IllegalArgumentException,
IllegalAccessException {
Field field = ReflectionHelper.getField(obj.getClass(), name);
return field.get(obj);
}
/**
* To get all uninitialized field you can call this method.
*
* @param obj the object where to get the fields from
*
* @return a collecion of unitialized fields (can be empty)
*/
public static Collection getUninitializedNonStaticFields(Object obj) {
Collection unitializedFields = new ArrayList();
Field[] fields = obj.getClass().getDeclaredFields();
for (int i = 0; i < fields.length; i++) {
try {
fields[i].setAccessible(true);
if ((fields[i].get(obj) == null) && !isStatic(fields[i])) {
unitializedFields.add(fields[i]);
}
} catch (IllegalArgumentException e) {
log.info(e + " => " + fields[i] + " ignored");
} catch (IllegalAccessException e) {
log.debug("can't access " + fields[i] + " => ignored");
}
}
return unitializedFields;
}
private static boolean isStatic(Field field) {
int m = field.getModifiers();
return Modifier.isStatic(m);
}
/**
* To short string.
*
* @param field the field
*
* @return the string
*/
public static String toShortString(Field field) {
return field.getType().getSimpleName() + " " + field.getName();
}
/**
* To short string.
*
* @param fields the fields
*
* @return the string
*/
public static String toShortString(Collection fields) {
StringBuffer sbuf = new StringBuffer();
for (Iterator iterator = fields.iterator(); iterator.hasNext();) {
Field field = iterator.next();
sbuf.append(", ");
sbuf.append(toShortString(field));
}
return sbuf.substring(2);
}
/**
* Gets the method.
*
* @param cl e.g. class java.lang.ClassLoader
* @param name e.g. "getPackages"
*
* @return a Method object
*
* @throws NoSuchMethodException the no such method exception
*/
public static Method getMethod(Class cl, String name) throws NoSuchMethodException {
try {
return cl.getDeclaredMethod(name);
} catch (NoSuchMethodException e) {
Class superclass = cl.getSuperclass();
if (superclass == null) {
throw e;
} else {
return getMethod(superclass, name);
}
}
}
}
/**
* $Log: ReflectionHelper.java,v $
* Revision 1.7 2009/12/19 22:34:09 oboehm
* trailing spaces removed
*
* Revision 1.6 2009/09/25 14:49:43 oboehm
* javadocs completed with the help of JAutodoc
*
* Revision 1.5 2009/09/18 13:54:52 oboehm
* javadoc warnings fixed
*
* Revision 1.4 2009/08/03 06:12:37 oboehm
* partially support of WLS classload (via getClasspathFromPackages)
*
* $Source: /cvsroot/patterntesting/PatternTesting08/patterntesting-rt/src/main/java/patterntesting/runtime/util/ReflectionHelper.java,v $
*/