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Posted to dev@ant.apache.org by pe...@apache.org on 2006/12/03 23:42:49 UTC
svn commit: r481956 - in /ant/core/trunk/src/main/org/apache/tools/ant/util:
ReflectUtil.java ReflectWrapper.java
Author: peterreilly
Date: Sun Dec 3 14:42:48 2006
New Revision: 481956
URL: http://svn.apache.org/viewvc?view=rev&rev=481956
Log:
helper classes for reflection
Added:
ant/core/trunk/src/main/org/apache/tools/ant/util/ReflectUtil.java
ant/core/trunk/src/main/org/apache/tools/ant/util/ReflectWrapper.java
Added: ant/core/trunk/src/main/org/apache/tools/ant/util/ReflectUtil.java
URL: http://svn.apache.org/viewvc/ant/core/trunk/src/main/org/apache/tools/ant/util/ReflectUtil.java?view=auto&rev=481956
==============================================================================
--- ant/core/trunk/src/main/org/apache/tools/ant/util/ReflectUtil.java (added)
+++ ant/core/trunk/src/main/org/apache/tools/ant/util/ReflectUtil.java Sun Dec 3 14:42:48 2006
@@ -0,0 +1,140 @@
+/*
+ * 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.apache.tools.ant.util;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import org.apache.tools.ant.BuildException;
+import java.lang.reflect.Field;
+
+/**
+ * Utility class to handle reflection on java objects.
+ * The class contains static methods to call reflection
+ * methods, catch any exceptions, converting them
+ * to BuildExceptions.
+ */
+
+public class ReflectUtil {
+
+ /** private constructor */
+ private ReflectUtil() {
+ }
+
+ /**
+ * Call a method on the object with no parameters.
+ * @param obj the object to invoke the method on.
+ * @param methodName the name of the method to call
+ * @return the object returned by the method
+ */
+ public static Object invoke(Object obj, String methodName) {
+ try {
+ Method method;
+ method = obj.getClass().getMethod(
+ methodName, (Class[]) null);
+ return method.invoke(obj, (Object[]) null);
+ } catch (Exception t) {
+ throwBuildException(t);
+ return null; // NotReached
+ }
+ }
+
+ /**
+ * Call a method on the object with one argument.
+ * @param obj the object to invoke the method on.
+ * @param methodName the name of the method to call
+ * @param argType the type of argument.
+ * @param arg the value of the argument.
+ * @return the object returned by the method
+ */
+ public static Object invoke(
+ Object obj, String methodName, Class argType, Object arg) {
+ try {
+ Method method;
+ method = obj.getClass().getMethod(
+ methodName, new Class[] {argType});
+ return method.invoke(obj, new Object[] {arg});
+ } catch (Exception t) {
+ throwBuildException(t);
+ return null; // NotReached
+ }
+ }
+
+ /**
+ * Call a method on the object with two argument.
+ * @param obj the object to invoke the method on.
+ * @param methodName the name of the method to call
+ * @param argType1 the type of the first argument.
+ * @param arg1 the value of the first argument.
+ * @param argType2 the type of the second argument.
+ * @param arg2 the value of the second argument.
+ * @return the object returned by the method
+ */
+ public static Object invoke(
+ Object obj, String methodName, Class argType1, Object arg1,
+ Class argType2, Object arg2) {
+ try {
+ Method method;
+ method = obj.getClass().getMethod(
+ methodName, new Class[] {argType1, argType2});
+ return method.invoke(obj, new Object[] {arg1, arg2});
+ } catch (Exception t) {
+ throwBuildException(t);
+ return null; // NotReached
+ }
+ }
+
+ /**
+ * Get the value of a field in an object.
+ * @param obj the object to look at.
+ * @param fieldName the name of the field in the object.
+ * @return the value of the field.
+ * @throws BuildException if there is an error.
+ */
+ public static Object getField(Object obj, String fieldName)
+ throws BuildException {
+ try {
+ Field field = obj.getClass().getDeclaredField(fieldName);
+ field.setAccessible(true);
+ return field.get(obj);
+ } catch (Exception t) {
+ throwBuildException(t);
+ return null; // NotReached
+ }
+ }
+
+ /**
+ * A method to convert an invocationTargetException to
+ * a buildexception and throw it.
+ * @param t the invocation target exception.
+ * @throws BuildException the converted exception.
+ */
+ public static void throwBuildException(Exception t)
+ throws BuildException {
+ if (t instanceof InvocationTargetException) {
+ Throwable t2 = ((InvocationTargetException) t)
+ .getTargetException();
+ if (t2 instanceof BuildException) {
+ throw (BuildException) t2;
+ }
+ throw new BuildException(t2);
+ } else {
+ throw new BuildException(t);
+ }
+ }
+}
Added: ant/core/trunk/src/main/org/apache/tools/ant/util/ReflectWrapper.java
URL: http://svn.apache.org/viewvc/ant/core/trunk/src/main/org/apache/tools/ant/util/ReflectWrapper.java?view=auto&rev=481956
==============================================================================
--- ant/core/trunk/src/main/org/apache/tools/ant/util/ReflectWrapper.java (added)
+++ ant/core/trunk/src/main/org/apache/tools/ant/util/ReflectWrapper.java Sun Dec 3 14:42:48 2006
@@ -0,0 +1,103 @@
+/*
+ * 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.apache.tools.ant.util;
+
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import org.apache.tools.ant.BuildException;
+import java.lang.reflect.Field;
+
+/**
+ * Utility class to handle reflection on java objects.
+ * The class is a holder class for an object and
+ * uses java reflection to call methods on the objects.
+ * If things go wrong, BuildExceptions are thrown.
+ */
+
+public class ReflectWrapper {
+ private Object obj;
+ /**
+ * Construct a wrapped object using the no arg constructor.
+ * @param loader the classloader to use to construct the class.
+ * @param name the classname of the object to construct.
+ */
+ public ReflectWrapper(ClassLoader loader, String name) {
+ try {
+ Class clazz;
+ clazz = Class.forName(name, true, loader);
+ Constructor constructor;
+ constructor = clazz.getConstructor((Class[]) null);
+ obj = constructor.newInstance((Object[]) null);
+ } catch (Exception t) {
+ ReflectUtil.throwBuildException(t);
+ }
+ }
+
+ /**
+ * Constructor using a passed in object.
+ * @param obj the object to wrap.
+ */
+ public ReflectWrapper(Object obj) {
+ this.obj = obj;
+ }
+
+ /**
+ * @return the wrapped object.
+ */
+ public Object getObject() {
+ return obj;
+ }
+
+ /**
+ * Call a method on the object with no parameters.
+ * @param methodName the name of the method to call
+ * @return the object returned by the method
+ */
+ public Object invoke(String methodName) {
+ return ReflectUtil.invoke(obj, methodName);
+ }
+
+ /**
+ * Call a method on the object with one argument.
+ * @param methodName the name of the method to call
+ * @param argType the type of argument.
+ * @param arg the value of the argument.
+ * @return the object returned by the method
+ */
+ public Object invoke(
+ String methodName, Class argType, Object arg) {
+ return ReflectUtil.invoke(obj, methodName, argType, arg);
+ }
+
+ /**
+ * Call a method on the object with one argument.
+ * @param methodName the name of the method to call
+ * @param argType1 the type of the first argument.
+ * @param arg1 the value of the first argument.
+ * @param argType2 the type of the second argument.
+ * @param arg2 the value of the second argument.
+ * @return the object returned by the method
+ */
+ public Object invoke(
+ String methodName, Class argType1, Object arg1,
+ Class argType2, Object arg2) {
+ return ReflectUtil.invoke(
+ obj, methodName, argType1, arg1, argType2, arg2);
+ }
+}
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