org.codehaus.groovy.reflection.ReflectionUtils Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.codehaus.groovy.reflection;
import java.util.Collection;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
/**
* This class contains utility methods to determine which class called the
* current class to multiple levels of depth. Calls used to handle the
* groovy MOP are excluded from the level counting.
*/
public class ReflectionUtils {
// these are packages in the call stack that are only part of the groovy MOP
private static final Set IGNORED_PACKAGES = new HashSet();
static {
//IGNORED_PACKAGES.add("java.lang.reflect");
IGNORED_PACKAGES.add("groovy.lang");
IGNORED_PACKAGES.add("org.codehaus.groovy.reflection");
IGNORED_PACKAGES.add("org.codehaus.groovy.runtime.callsite");
IGNORED_PACKAGES.add("org.codehaus.groovy.runtime.metaclass");
IGNORED_PACKAGES.add("org.codehaus.groovy.runtime");
IGNORED_PACKAGES.add("sun.reflect");
IGNORED_PACKAGES.add("java.lang.invoke");
IGNORED_PACKAGES.add("org.codehaus.groovy.vmplugin.v7");
}
private static final ClassContextHelper HELPER = new ClassContextHelper();
/**
* Determine whether or not the getCallingClass methods will return
* any sensible results. On JVMs that are not Sun derived i.e.
* (gcj, Harmony) this will likely return false. When not available
* all getCallingClass methods will return null.
*
* @return true if getCallingClass can return anything but null, false if
* it will only return null.
*/
public static boolean isCallingClassReflectionAvailable() {
return true;
}
/**
* Get the immediate calling class, ignoring MOP frames.
*
* @return The Class of the caller
*/
public static Class getCallingClass() {
return getCallingClass(1);
}
/**
* Get the called that is matchLevel stack frames before the call,
* ignoring MOP frames.
*
* @param matchLevel how may call stacks down to look.
* If it is less than 1 it is treated as though it was 1.
* @return The Class of the matched caller, or null if there aren't
* enough stackframes to satisfy matchLevel
*/
public static Class getCallingClass(int matchLevel) {
return getCallingClass(matchLevel, Collections.EMPTY_SET);
}
/**
* Get the called that is matchLevel stack frames before the call,
* ignoring MOP frames and desired exclude packages.
*
* @param matchLevel how may call stacks down to look.
* If it is less than 1 it is treated as though it was 1.
* @param extraIgnoredPackages A collection of string names of packages to exclude
* in addition to the MOP packages when counting stack frames.
* @return The Class of the matched caller, or null if there aren't
* enough stackframes to satisfy matchLevel
*/
public static Class getCallingClass(int matchLevel, Collection extraIgnoredPackages) {
Class[] classContext = HELPER.getClassContext();
int depth = 0;
try {
Class c;
// this super class stuff is for Java 1.4 support only
// it isn't needed on a 5.0 VM
Class sc;
do {
do {
c = classContext[depth++];
if (c != null) {
sc = c.getSuperclass();
} else {
sc = null;
}
} while (classShouldBeIgnored(c, extraIgnoredPackages)
|| superClassShouldBeIgnored(sc));
} while (c != null && matchLevel-- > 0 && depth extraIgnoredPackages) {
return ((c != null)
&& (c.isSynthetic()
|| (c.getPackage() != null
&& (IGNORED_PACKAGES.contains(c.getPackage().getName())
|| extraIgnoredPackages.contains(c.getPackage().getName())))));
}
private static class ClassContextHelper extends SecurityManager {
@Override
public Class[] getClassContext() {
return super.getClassContext();
}
}
}