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Ladybug adds message based debugging and message based unit testing and system testing to your Java application. Call
Ladybug at certain checkpoints in you code (either directly or using AOP) to generate tree based reports. Implement a
rerun method to be able to rerun reports and optionally stub certain checkpoints for regression testing.
/*
* Copyright (c) 2008, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package nl.nn.xmldecoder.finder;
import java.util.HashMap;
import java.util.Map;
/**
* This abstract class provides functionality
* to find a public method or constructor
* with specified parameter types.
* It supports a variable number of parameters.
*
* @since 1.7
*
* @author Sergey A. Malenkov
*/
abstract class AbstractFinder {
private final Class[] args;
/**
* Creates finder for array of classes of arguments.
* If a particular element of array equals {@code null},
* than the appropriate pair of classes
* does not take into consideration.
*
* @param args array of classes of arguments
*/
protected AbstractFinder(Class[] args) {
this.args = args;
}
/**
* Returns an array of {@code Class} objects
* that represent the formal parameter types of the method
* Returns an empty array if the method takes no parameters.
*
* @param method the object that represents method
* @return the parameter types of the method
*/
protected abstract Class[] getParameters(T method);
/**
* Returns {@code true} if and only if the method
* was declared to take a variable number of arguments.
*
* @param method the object that represents method
* @return {@code true} if the method was declared
* to take a variable number of arguments;
* {@code false} otherwise
*/
protected abstract boolean isVarArgs(T method);
/**
* Checks validness of the method.
* At least the valid method should be public.
*
* @param method the object that represents method
* @return {@code true} if the method is valid,
* {@code false} otherwise
*/
protected abstract boolean isValid(T method);
/**
* Performs a search in the {@code methods} array.
* The one method is selected from the array of the valid methods.
* The list of parameters of the selected method shows
* the best correlation with the list of arguments
* specified at class initialization.
* If more than one method is both accessible and applicable
* to a method invocation, it is necessary to choose one
* to provide the descriptor for the run-time method dispatch.
* The most specific method should be chosen.
*
* @param methods the array of methods to search within
* @return the object that represents found method
* @throws NoSuchMethodException if no method was found or several
* methods meet the search criteria
* @see #isAssignable
*/
final T find(T[] methods) throws NoSuchMethodException {
Map[]> map = new HashMap[]>();
T oldMethod = null;
Class[] oldParams = null;
boolean ambiguous = false;
for (T newMethod : methods) {
if (isValid(newMethod)) {
Class[] newParams = getParameters(newMethod);
if (newParams.length == this.args.length) {
PrimitiveWrapperMap.replacePrimitivesWithWrappers(newParams);
if (isAssignable(newParams, this.args)) {
if (oldMethod == null) {
oldMethod = newMethod;
oldParams = newParams;
} else {
boolean useNew = isAssignable(oldParams, newParams);
boolean useOld = isAssignable(newParams, oldParams);
if (useOld == useNew) {
ambiguous = true;
} else if (useNew) {
oldMethod = newMethod;
oldParams = newParams;
ambiguous = false;
}
}
}
}
if (isVarArgs(newMethod)) {
int length = newParams.length - 1;
if (length <= this.args.length) {
Class[] array = new Class[this.args.length];
System.arraycopy(newParams, 0, array, 0, length);
if (length < this.args.length) {
Class type = newParams[length].getComponentType();
if (type.isPrimitive()) {
type = PrimitiveWrapperMap.getType(type.getName());
}
for (int i = length; i < this.args.length; i++) {
array[i] = type;
}
}
map.put(newMethod, array);
}
}
}
}
for (T newMethod : methods) {
Class[] newParams = map.get(newMethod);
if (newParams != null) {
if (isAssignable(newParams, this.args)) {
if (oldMethod == null) {
oldMethod = newMethod;
oldParams = newParams;
} else {
boolean useNew = isAssignable(oldParams, newParams);
boolean useOld = isAssignable(newParams, oldParams);
if (useOld == useNew) {
if (oldParams == map.get(oldMethod)) {
ambiguous = true;
}
} else if (useNew) {
oldMethod = newMethod;
oldParams = newParams;
ambiguous = false;
}
}
}
}
}
if (ambiguous) {
throw new NoSuchMethodException("Ambiguous methods are found");
}
if (oldMethod == null) {
throw new NoSuchMethodException("Method is not found");
}
return oldMethod;
}
/**
* Determines if every class in {@code min} array is either the same as,
* or is a superclass of, the corresponding class in {@code max} array.
* The length of every array must equal the number of arguments.
* This comparison is performed in the {@link #find} method
* before the first call of the isAssignable method.
* If an argument equals {@code null}
* the appropriate pair of classes does not take into consideration.
*
* @param min the array of classes to be checked
* @param max the array of classes that is used to check
* @return {@code true} if all classes in {@code min} array
* are assignable from corresponding classes in {@code max} array,
* {@code false} otherwise
*
* @see Class#isAssignableFrom
*/
private boolean isAssignable(Class[] min, Class[] max) {
for (int i = 0; i < this.args.length; i++) {
if (null != this.args[i]) {
if (!min[i].isAssignableFrom(max[i])) {
return false;
}
}
}
return true;
}
}