--- /dev/null
+/*
+ * Copyright 2004-2012 Sebastian Dietrich (Sebastian.Dietrich@e-movimento.com)
+ *
+ * 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 or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package junit.extensions;
+
+import java.util.Collection;
+
+/**
+ * This class is used to access a method or field of an object no matter what the access modifier of the method or field. The syntax
+ * for accessing fields and methods is out of the ordinary because this class uses reflection to peel away protection.
+ * <p>
+ * a.k.a. The "ObjectMolester"
+ * <p>
+ * Here is an example of using this to access a private member: <br>
+ * Given the following class <code>MyClass</code>: <br>
+ *
+ * <pre>
+ * public class MyClass {
+ * private String name; // private attribute
+ *
+ * // private constructor
+ * private MyClass() {
+ * super();
+ * }
+ *
+ * // private method
+ * private void setName(String newName) {
+ * this.name = newName;
+ * }
+ * }
+ * </pre>
+ *
+ * We now want to access the class: <br>
+ *
+ * <pre>
+ * MyClass myObj = PA.instantiate(MyClass.class);
+ * PA.invokeMethod(myObj, "setName(java.lang.String)", "myNewName");
+ * String name = PA.getValue(myObj, "name");
+ * </pre>
+ *
+ * This class extends {@link PrivilegedAccessor} by re-throwing checked {@link Exception}s as {@link RuntimeException}s.
+ *
+ *
+ * @see PrivilegedAccessor
+ *
+ * @author Sebastian Dietrich (sebastian.dietrich@e-movimento.com)
+ * @author Lubos Bistak (lubos@bistak.sk)
+ */
+public class PA {
+ private final Object instanceOrClass;
+
+ /**
+ * Private constructor to make it impossible to instantiate this class from outside of PA.
+ *
+ * @param instanceOrClass
+ */
+ private PA(Object instanceOrClass) {
+ this.instanceOrClass = instanceOrClass;
+ }
+
+ /**
+ * Returns a string representation of the given object. The string has the following format: "<classname> {<attributes and values>}"
+ * whereas <attributes and values> is a comma separated list with <attributeName>=<attributeValue> <atributes and values> includes
+ * all attributes of the objects class followed by the attributes of its superclass (if any) and so on.
+ *
+ * @param instanceOrClass the object or class to get a string representation of
+ * @return a string representation of the given object
+ *
+ * @see PrivilegedAccessor#toString(Object)
+ */
+ public static String toString(final Object instanceOrClass) {
+ return PrivilegedAccessor.toString(instanceOrClass);
+ }
+
+ /**
+ * Gets the name of all fields (public, private, protected, default) of the given instance or class. This includes as well all
+ * fields (public, private, protected, default) of all its super classes.
+ *
+ * @param instanceOrClass the instance or class to get the fields of
+ * @return the collection of field names of the given instance or class
+ *
+ * @see PrivilegedAccessor#getFieldNames(Object)
+ */
+ public static Collection<String> getFieldNames(final Object instanceOrClass) {
+ return PrivilegedAccessor.getFieldNames(instanceOrClass);
+ }
+
+ /**
+ * Gets the signatures of all methods (public, private, protected, default) of the given instance or class. This includes as well
+ * all methods (public, private, protected, default) of all its super classes. This does not include constructors.
+ *
+ * @param instanceOrClass the instance or class to get the method signatures of
+ * @return the collection of method signatures of the given instance or class
+ *
+ * @see PrivilegedAccessor#getMethodSignatures(Object)
+ */
+ public static Collection<String> getMethodSignatures(final Object instanceOrClass) {
+ return PrivilegedAccessor.getMethodSignatures(instanceOrClass);
+ }
+
+ /**
+ * Gets the value of the named field and returns it as an object. If instanceOrClass is a class then a static field is returned.
+ *
+ * @param instanceOrClass the instance or class to get the field from
+ * @param fieldName the name of the field
+ * @return an object representing the value of the field
+ * @throws IllegalArgumentException if the field does not exist
+ *
+ * @see PrivilegedAccessor#getValue(Object,String)
+ */
+ public static Object getValue(final Object instanceOrClass, final String fieldName) {
+ try {
+ return PrivilegedAccessor.getValue(instanceOrClass, fieldName);
+ } catch (Exception e) {
+ throw new IllegalArgumentException("Can't get value of " + fieldName + " from " + instanceOrClass, e);
+ }
+ }
+
+ /**
+ * Gets the value of the named field and returns it as an object.
+ *
+ * @param fieldName the name of the field
+ * @return an object representing the value of the field
+ * @throws IllegalArgumentException if the field does not exist
+ *
+ * @see PA#getValue(Object,String)
+ */
+ public Object getValue(final String fieldName) {
+ return PA.getValue(instanceOrClass, fieldName);
+ }
+
+ /**
+ * Instantiates an object of the given class with the given arguments and the given argument types. If you want to instantiate a
+ * member class, you must provide the object it is a member of as first argument.
+ *
+ * @param fromClass the class to instantiate an object from
+ * @param arguments the arguments to pass to the constructor
+ * @param argumentTypes the fully qualified types of the arguments of the constructor
+ * @return an object of the given type
+ * @throws IllegalArgumentException if the class can't be instantiated. This could be the case if the number of actual and formal
+ * parameters differ; if an unwrapping conversion for primitive arguments fails; if, after possible unwrapping, a
+ * parameter value cannot be converted to the corresponding formal parameter type by a method invocation conversion; if
+ * this Constructor object enforces Java language access control and the underlying constructor is inaccessible; if the
+ * underlying constructor throws an exception; if the constructor could not be found; or if the class that declares the
+ * underlying constructor represents an abstract class.
+ *
+ * @see PrivilegedAccessor#instantiate(Class,Class[],Object[])
+ */
+ public static <T> T instantiate(final Class<? extends T> fromClass, final Class<?>[] argumentTypes, final Object... arguments) {
+ try {
+ return PrivilegedAccessor.instantiate(fromClass, argumentTypes, correctVarargs(arguments));
+ } catch (Exception e) {
+ throw new IllegalArgumentException("Can't instantiate class " + fromClass + " with arguments " + arguments, e);
+ }
+ }
+
+ /**
+ * Instantiates an object of the given class with the given arguments. If you want to instantiate a member class, you must provide
+ * the object it is a member of as first argument.
+ *
+ * @param fromClass the class to instantiate an object from
+ * @param arguments the arguments to pass to the constructor
+ * @return an object of the given type
+ * @throws IllegalArgumentException if the class can't be instantiated. This could be the case if the number of actual and formal
+ * parameters differ; if an unwrapping conversion for primitive arguments fails; or if, after possible unwrapping, a
+ * parameter value cannot be converted to the corresponding formal parameter type by a method invocation conversion; if
+ * this Constructor object enforces Java language access control and the underlying constructor is inaccessible; if the
+ * underlying constructor throws an exception; if the constructor could not be found; or if the class that declares the
+ * underlying constructor represents an abstract class.
+ *
+ * @see PrivilegedAccessor#instantiate(Class,Object[])
+ */
+ public static <T> T instantiate(final Class<? extends T> fromClass, final Object... arguments) {
+ try {
+ return PrivilegedAccessor.instantiate(fromClass, correctVarargs(arguments));
+ } catch (Exception e) {
+ throw new IllegalArgumentException("Can't instantiate class " + fromClass + " with arguments " + arguments, e);
+ }
+ }
+
+ /**
+ * Calls a method on the given object instance with the given arguments. Arguments can be object types or representations for
+ * primitives.
+ *
+ * @param instanceOrClass the instance or class to invoke the method on
+ * @param methodSignature the name of the method and the parameters <br>
+ * (e.g. "myMethod(java.lang.String, com.company.project.MyObject)")
+ * @param arguments an array of objects to pass as arguments
+ * @return the return value of this method or null if void
+ * @throws IllegalArgumentException if the method could not be invoked. This could be the case if the method is inaccessible; if the
+ * underlying method throws an exception; if no method with the given <code>methodSignature</code> could be found; or if
+ * an argument couldn't be converted to match the expected type
+ *
+ * @see PrivilegedAccessor#invokeMethod(Object,String,Object[])
+ */
+ public static Object invokeMethod(final Object instanceOrClass, final String methodSignature, final Object... arguments) {
+ try {
+ return PrivilegedAccessor.invokeMethod(instanceOrClass, methodSignature, correctVarargs(arguments));
+ } catch (Exception e) {
+ throw new IllegalArgumentException("Can't invoke method " + methodSignature + " on " + instanceOrClass + " with arguments "
+ + arguments, e);
+ }
+ }
+
+ /**
+ * Calls a method with the given arguments. Arguments can be object types or representations for primitives.
+ *
+ * @param methodSignature the name of the method and the parameters <br>
+ * (e.g. "myMethod(java.lang.String, com.company.project.MyObject)")
+ * @param arguments an array of objects to pass as arguments
+ * @return the return value of this method or null if void
+ * @throws IllegalArgumentException if the method could not be invoked. This could be the case if the method is inaccessible; if the
+ * underlying method throws an exception; if no method with the given <code>methodSignature</code> could be found; or if
+ * an argument couldn't be converted to match the expected type
+ * @see PA#invokeMethod(Object, String, Object...)
+ */
+ public Object invokeMethod(final String methodSignature, final Object... arguments) {
+ return PA.invokeMethod(instanceOrClass, methodSignature, arguments);
+ }
+
+ /**
+ * Corrects varargs to their initial form. If you call a method with an object-array as last argument the Java varargs mechanism
+ * converts this array in single arguments. This method returns an object array if the arguments are all of the same type.
+ *
+ * @param arguments the possibly converted arguments of a vararg method
+ * @return arguments possibly converted
+ */
+ private static Object[] correctVarargs(final Object... arguments) {
+ if ((arguments == null) || changedByVararg(arguments)) return new Object[] {arguments};
+ return arguments;
+ }
+
+ /**
+ * Tests if the arguments were changed by vararg. Arguments are changed by vararg if they are of a non primitive array type. E.g.
+ * arguments[] = Object[String[]] is converted to String[] while e.g. arguments[] = Object[int[]] is not converted and stays
+ * Object[int[]]
+ *
+ * Unfortunately we can't detect the difference for arg = Object[primitive] since arguments[] = Object[Object[primitive]] which is
+ * converted to Object[primitive] and arguments[] = Object[primitive] which stays Object[primitive]
+ *
+ * and we can't detect the difference for arg = Object[non primitive] since arguments[] = Object[Object[non primitive]] is converted
+ * to Object[non primitive] and arguments[] = Object[non primitive] stays Object[non primitive]
+ *
+ * @param parameters the parameters
+ * @return true if parameters were changes by varargs, false otherwise
+ */
+ private static boolean changedByVararg(final Object[] parameters) {
+ if ((parameters.length == 0) || (parameters[0] == null)) return false;
+
+ if (parameters.getClass() == Object[].class) return false;
+
+ return true;
+ }
+
+ /**
+ * Sets the value of the named field. If fieldName denotes a static field, provide a class, otherwise provide an instance. If the
+ * fieldName denotes a final field, this method could fail with an IllegalAccessException, since setting the value of final fields
+ * at other times than instantiation can have unpredictable effects.<br/>
+ * <br/>
+ * Example:<br/>
+ * <br/>
+ * <code>
+ * String myString = "Test"; <br/>
+ * <br/>
+ * //setting the private field value<br/>
+ * PrivilegedAccessor.setValue(myString, "value", new char[] {'T', 'e', 's', 't'});<br/>
+ * <br/>
+ * //setting the static final field serialVersionUID - MIGHT FAIL<br/>
+ * PrivilegedAccessor.setValue(myString.getClass(), "serialVersionUID", 1);<br/>
+ * <br/>
+ * </code>
+ *
+ * @param instanceOrClass the instance or class to set the field
+ * @param fieldName the name of the field
+ * @param value the new value of the field
+ * @throws IllegalArgumentException if the value could not be set. This could be the case if no field with the given
+ * <code>fieldName</code> can be found; or if the field was final
+ *
+ * @see PrivilegedAccessor.setValue(Object,String,Object)
+ */
+ public static PA setValue(final Object instanceOrClass, final String fieldName, final Object value) {
+ try {
+ PrivilegedAccessor.setValue(instanceOrClass, fieldName, value);
+ } catch (Exception e) {
+ throw new IllegalArgumentException("Can't set value " + value + " at " + fieldName + " in " + instanceOrClass, e);
+ }
+ return new PA(instanceOrClass);
+ }
+
+ /**
+ * Sets the value of the named field. If fieldName denotes a static field, provide a class, otherwise provide an instance. If the
+ * fieldName denotes a final field, this method could fail with an IllegalAccessException, since setting the value of final fields
+ * at other times than instantiation can have unpredictable effects.<br/>
+ * <br/>
+ * Example:<br/>
+ * <br/>
+ * <code>
+ * String myString = "Test"; <br/>
+ * <br/>
+ * //setting the private field value<br/>
+ * PrivilegedAccessor.setValue(myString, "value", new char[] {'T', 'e', 's', 't'});<br/>
+ * <br/>
+ * //setting the static final field serialVersionUID - MIGHT FAIL<br/>
+ * PrivilegedAccessor.setValue(myString.getClass(), "serialVersionUID", 1);<br/>
+ * <br/>
+ * </code>
+ *
+ * @param fieldName the name of the field
+ * @param value the new value of the field
+ * @throws IllegalArgumentException if the value could not be set. This could be the case if no field with the given
+ * <code>fieldName</code> can be found; or if the field was final
+ *
+ * @see PA.setValue(Object,String,Object)
+ */
+ public PA setValue(final String fieldName, final Object value) {
+ PA.setValue(instanceOrClass, fieldName, value);
+ return this;
+ }
+}
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