openjpa-kernel/src/main/java/org/apache/openjpa/enhance/Reflection.java - openjpa - Git at Google

 /*
  * 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.openjpa.enhance;

 import java.lang.reflect.AccessibleObject;
 import java.lang.reflect.Field;
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
 import java.security.AccessController;

 import org.apache.commons.lang.StringUtils;
 import org.apache.openjpa.lib.util.J2DoPrivHelper;
 import org.apache.openjpa.lib.util.Localizer;
 import org.apache.openjpa.util.GeneralException;
 import org.apache.openjpa.util.UserException;

 /**
  * Reflection utilities used to support and augment enhancement.  Used both
  * at enhancement time and at runtime.
  *
  * @author Abe White
  */
 public class Reflection {

     private static final Localizer _loc = Localizer.forPackage
         (Reflection.class);

     /**
      * Return the getter method matching the given property name, optionally
      * throwing an exception if none.
      */
     public static Method findGetter(Class cls, String prop, boolean mustExist) {
         prop = StringUtils.capitalize(prop);
         String name = "get" + prop;
         Method m;
         try {
             // this algorithm searches for a get<prop> or is<prop> method in
             // a breadth-first manner.
             for (Class c = cls; c != null && c != Object.class;
                 c = c.getSuperclass()) {
                 m = getDeclaredMethod(c, name, null);
                 if (m != null) {
                     return m;
                 } else {
                     m = getDeclaredMethod(c, "is" + prop, null);
                     if (m != null && (m.getReturnType() == boolean.class
                         || m.getReturnType() == Boolean.class))
                         return m;
                 }
             }
         } catch (Exception e) {
             throw new GeneralException(e);
         }

         if (mustExist)
             throw new UserException(_loc.get("bad-getter", cls, prop));
         return null;
     }

     /**
      * Return the setter method matching the given property name, optionally
      * throwing an exception if none.  The property must also have a getter.
      */
     public static Method findSetter(Class cls, String prop, boolean mustExist) {
         Method getter = findGetter(cls, prop, mustExist);
         return (getter == null) ? null
             : findSetter(cls, prop, getter.getReturnType(), mustExist);
     }

     /**
      * Return the setter method matching the given property name, optionally
      * throwing an exception if none.
      */
     public static Method findSetter(Class cls, String prop, Class param,
         boolean mustExist) {
         String name = "set" + StringUtils.capitalize(prop);
         Method m;
         try {
             for (Class c = cls; c != null && c != Object.class;
                 c = c.getSuperclass()) {
                 m = getDeclaredMethod(c, name, param);
                 if (m != null)
                     return m;
             }
         } catch (Exception e) {
             throw new GeneralException(e);
         }

         if (mustExist)
             throw new UserException(_loc.get("bad-setter", cls, prop));
         return null;
     }

     /**
      * Invokes <code>cls.getDeclaredMethods()</code>, and returns the method
      * that matches the <code>name</code> and <code>param</code> arguments.
      * Avoids the exception thrown by <code>Class.getDeclaredMethod()</code>
      * for performance reasons. <code>param</code> may be null. Additionally,
      * if there are multiple methods with different return types, this will
      * return the method defined in the least-derived class.
      *
      * @since 0.9.8
      */
     static Method getDeclaredMethod(Class cls, String name,
         Class param) {
         Method[] methods = (Method[]) AccessController.doPrivileged(
             J2DoPrivHelper.getDeclaredMethodsAction(cls));
         Method candidate = null;
         for (int i = 0 ; i < methods.length; i++) {
     	    if (name.equals(methods[i].getName())) {
                 Class[] methodParams = methods[i].getParameterTypes();
                 if (param == null && methodParams.length == 0)
                     candidate = mostDerived(methods[i], candidate);
                 else if (param != null && methodParams.length == 1
                     && param.equals(methodParams[0]))
                     candidate = mostDerived(methods[i], candidate);
             }
         }
         return candidate;
     }

     static Method mostDerived(Method meth1, Method meth2) {
         if (meth1 == null)
             return meth2;
         if (meth2 == null)
             return meth1;

         Class cls2 = meth2.getDeclaringClass();
         Class cls1 = meth1.getDeclaringClass();

         if (cls1.equals(cls2)) {
             Class ret1 = meth1.getReturnType();
             Class ret2 = meth2.getReturnType();
             if (ret1.isAssignableFrom(ret2))
                 return meth2;
             else if (ret2.isAssignableFrom(ret1))
                 return meth1;
             else
                 throw new IllegalArgumentException(
                     _loc.get("most-derived-unrelated-same-type", meth1, meth2)
                         .getMessage());
         } else {
             if (cls1.isAssignableFrom(cls2))
                 return meth2;
             else if (cls2.isAssignableFrom(cls1))
                 return meth1;
             else
                 throw new IllegalArgumentException(
                     _loc.get("most-derived-unrelated", meth1, meth2)
                         .getMessage());
         }
     }

     /**
      * Return the field with the given name, optionally throwing an exception
      * if none.
      */
     public static Field findField(Class cls, String name, boolean mustExist) {
         try {
             Field f;
             for (Class c = cls; c != null && c != Object.class;
                 c = c.getSuperclass()) {
                 f = getDeclaredField(c, name);
                 if (f != null)
                     return f;
             }
         } catch (Exception e) {
             throw new GeneralException(e);
         }

         if (mustExist)
             throw new UserException(_loc.get("bad-field", cls, name));
         return null;
     }

     /**
      * Invokes <code>cls.getDeclaredFields()</code>, and returns the field
      * that matches the <code>name</code> argument.  Avoids the exception
      * thrown by <code>Class.getDeclaredField()</code> for performance reasons.
      *
      * @since 0.9.8
      */
     private static Field getDeclaredField(Class cls, String name) {
         Field[] fields = (Field[]) AccessController.doPrivileged(
             J2DoPrivHelper.getDeclaredFieldsAction(cls));
         for (int i = 0 ; i < fields.length; i++) {
     	    if (name.equals(fields[i].getName()))
 		        return fields[i];
         }
         return null;
     }

     /**
      * Return the value of the given field in the given object.
      */
     public static Object get(Object target, Field field) {
         if (target == null || field == null)
             return null;
         makeAccessible(field, field.getModifiers());
         try {
             return field.get(target);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Get the value of the given named field or a corresponding getter method.
      *
      * @return null if the field does not exist and mustExist is set to false or
      * the given target is null.
      *
      * @exception UserException if mustExist is true and the field or getter
      * method is non-existent
      */
     public static Object getValue(Object obj, String prop, boolean mustExist) {
     	if (obj == null)
     		return null;
     	Class cls = obj.getClass();
     	Field field = findField(cls, prop, false);
     	if (field != null)
     		return get(obj, field);
     	Method getter = findGetter(cls, prop, false);
     	if (getter != null)
     		return get(obj, getter);
         if (mustExist)
             throw new UserException(_loc.get("bad-field", cls, prop));
         return null; // should not reach
     }

     /**
      * Make the given member accessible if it isn't already.
      */
     private static void makeAccessible(AccessibleObject ao, int mods) {
         try {
             if (!Modifier.isPublic(mods) && !ao.isAccessible())
                 AccessController.doPrivileged(J2DoPrivHelper
                     .setAccessibleAction(ao, true));
         } catch (SecurityException se) {
             throw new UserException(_loc.get("reflect-security", ao)).
                 setFatal(true);
         }
     }

     /**
      * Wrap the given reflection exception as a runtime exception.
      */
     private static RuntimeException wrapReflectionException(Throwable t) {
         if (t instanceof InvocationTargetException)
             t = ((InvocationTargetException) t).getTargetException();
         if (t instanceof RuntimeException)
             return (RuntimeException) t;
         return new GeneralException(t);
     }

     /**
      * Return the value of the given field in the given object.
      */
     public static boolean getBoolean(Object target, Field field) {
         if (target == null || field == null)
             return false;
         makeAccessible(field, field.getModifiers());
         try {
             return field.getBoolean(target);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Return the value of the given field in the given object.
      */
     public static byte getByte(Object target, Field field) {
         if (target == null || field == null)
             return (byte) 0;
         makeAccessible(field, field.getModifiers());
         try {
             return field.getByte(target);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Return the value of the given field in the given object.
      */
     public static char getChar(Object target, Field field) {
         if (target == null || field == null)
             return (char) 0;
         makeAccessible(field, field.getModifiers());
         try {
             return field.getChar(target);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Return the value of the given field in the given object.
      */
     public static double getDouble(Object target, Field field) {
         if (target == null || field == null)
             return 0D;
         makeAccessible(field, field.getModifiers());
         try {
             return field.getDouble(target);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Return the value of the given field in the given object.
      */
     public static float getFloat(Object target, Field field) {
         if (target == null || field == null)
             return 0F;
         makeAccessible(field, field.getModifiers());
         try {
             return field.getFloat(target);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Return the value of the given field in the given object.
      */
     public static int getInt(Object target, Field field) {
         if (target == null || field == null)
             return 0;
         makeAccessible(field, field.getModifiers());
         try {
             return field.getInt(target);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Return the value of the given field in the given object.
      */
     public static long getLong(Object target, Field field) {
         if (target == null || field == null)
             return 0L;
         makeAccessible(field, field.getModifiers());
         try {
             return field.getLong(target);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Return the value of the given field in the given object.
      */
     public static short getShort(Object target, Field field) {
         if (target == null || field == null)
             return (short) 0;
         makeAccessible(field, field.getModifiers());
         try {
             return field.getShort(target);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Return the return value of the given getter in the given object.
      */
     public static Object get(Object target, Method getter) {
         if (target == null || getter == null)
             return null;
         makeAccessible(getter, getter.getModifiers());
         try {
             return getter.invoke(target, (Object[]) null);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Return the return value of the given getter in the given object.
      */
     public static boolean getBoolean(Object target, Method getter) {
         Object o = get(target, getter);
         return (o == null) ? false : ((Boolean) o).booleanValue();
     }

     /**
      * Return the return value of the given getter in the given object.
      */
     public static byte getByte(Object target, Method getter) {
         Object o = get(target, getter);
         return (o == null) ? (byte) 0 : ((Number) o).byteValue();
     }

     /**
      * Return the return value of the given getter in the given object.
      */
     public static char getChar(Object target, Method getter) {
         Object o = get(target, getter);
         return (o == null) ? (char) 0 : ((Character) o).charValue();
     }

     /**
      * Return the return value of the given getter in the given object.
      */
     public static double getDouble(Object target, Method getter) {
         Object o = get(target, getter);
         return (o == null) ? 0D : ((Number) o).doubleValue();
     }

     /**
      * Return the return value of the given getter in the given object.
      */
     public static float getFloat(Object target, Method getter) {
         Object o = get(target, getter);
         return (o == null) ? 0F : ((Number) o).floatValue();
     }

     /**
      * Return the return value of the given getter in the given object.
      */
     public static int getInt(Object target, Method getter) {
         Object o = get(target, getter);
         return (o == null) ? 0 : ((Number) o).intValue();
     }

     /**
      * Return the return value of the given getter in the given object.
      */
     public static long getLong(Object target, Method getter) {
         Object o = get(target, getter);
         return (o == null) ? 0L : ((Number) o).longValue();
     }

     /**
      * Return the return value of the given getter in the given object.
      */
     public static short getShort(Object target, Method getter) {
         Object o = get(target, getter);
         return (o == null) ? (short) 0 : ((Number) o).shortValue();
     }

     /**
      * Set the value of the given field in the given object.
      */
     public static void set(Object target, Field field, Object value) {
         if (target == null || field == null)
             return;
         makeAccessible(field, field.getModifiers());
         try {
             field.set(target, value);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Set the value of the given field in the given object.
      */
     public static void set(Object target, Field field, boolean value) {
         if (target == null || field == null)
             return;
         makeAccessible(field, field.getModifiers());
         try {
             field.setBoolean(target, value);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Set the value of the given field in the given object.
      */
     public static void set(Object target, Field field, byte value) {
         if (target == null || field == null)
             return;
         makeAccessible(field, field.getModifiers());
         try {
             field.setByte(target, value);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Set the value of the given field in the given object.
      */
     public static void set(Object target, Field field, char value) {
         if (target == null || field == null)
             return;
         makeAccessible(field, field.getModifiers());
         try {
             field.setChar(target, value);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Set the value of the given field in the given object.
      */
     public static void set(Object target, Field field, double value) {
         if (target == null || field == null)
             return;
         makeAccessible(field, field.getModifiers());
         try {
             field.setDouble(target, value);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Set the value of the given field in the given object.
      */
     public static void set(Object target, Field field, float value) {
         if (target == null || field == null)
             return;
         makeAccessible(field, field.getModifiers());
         try {
             field.setFloat(target, value);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Set the value of the given field in the given object.
      */
     public static void set(Object target, Field field, int value) {
         if (target == null || field == null)
             return;
         makeAccessible(field, field.getModifiers());
         try {
             field.setInt(target, value);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Set the value of the given field in the given object.
      */
     public static void set(Object target, Field field, long value) {
         if (target == null || field == null)
             return;
         makeAccessible(field, field.getModifiers());
         try {
             field.setLong(target, value);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Set the value of the given field in the given object.
      */
     public static void set(Object target, Field field, short value) {
         if (target == null || field == null)
             return;
         makeAccessible(field, field.getModifiers());
         try {
             field.setShort(target, value);
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Set the value of the given field in the given object.
      * Same behavior as above methods, but parameter ordering is rearranged
      * to simplify usage from generated bytecodes.
      *
      * @since 1.0.0
      */
     public static void set(Object target, Object value, Field field) {
         set(target, field, value);
     }

     /**
      * Set the value of the given field in the given object.
      * Same behavior as above methods, but parameter ordering is rearranged
      * to simplify usage from generated bytecodes.
      *
      * @since 1.0.0
      */
     public static void set(Object target, boolean value, Field field) {
         set(target, field, value);
     }

     /**
      * Set the value of the given field in the given object.
      * Same behavior as above methods, but parameter ordering is rearranged
      * to simplify usage from generated bytecodes.
      *
      * @since 1.0.0
      */
     public static void set(Object target, byte value, Field field) {
         set(target, field, value);
     }

     /**
      * Set the value of the given field in the given object.
      * Same behavior as above methods, but parameter ordering is rearranged
      * to simplify usage from generated bytecodes.
      *
      * @since 1.0.0
      */
     public static void set(Object target, char value, Field field) {
         set(target, field, value);
     }

     /**
      * Set the value of the given field in the given object.
      * Same behavior as above methods, but parameter ordering is rearranged
      * to simplify usage from generated bytecodes.
      *
      * @since 1.0.0
      */
     public static void set(Object target, double value, Field field) {
         set(target, field, value);
     }

     /**
      * Set the value of the given field in the given object.
      * Same behavior as above methods, but parameter ordering is rearranged
      * to simplify usage from generated bytecodes.
      *
      * @since 1.0.0
      */
     public static void set(Object target, float value, Field field) {
         set(target, field, value);
     }

     /**
      * Set the value of the given field in the given object.
      * Same behavior as above methods, but parameter ordering is rearranged
      * to simplify usage from generated bytecodes.
      *
      * @since 1.0.0
      */
     public static void set(Object target, int value, Field field) {
         set(target, field, value);
     }

     /**
      * Set the value of the given field in the given object.
      * Same behavior as above methods, but parameter ordering is rearranged
      * to simplify usage from generated bytecodes.
      *
      * @since 1.0.0
      */
     public static void set(Object target, long value, Field field) {
         set(target, field, value);
     }

     /**
      * Set the value of the given field in the given object.
      * Same behavior as above methods, but parameter ordering is rearranged
      * to simplify usage from generated bytecodes.
      *
      * @since 1.0.0
      */
     public static void set(Object target, short value, Field field) {
         set(target, field, value);
     }

     /**
      * Invoke the given setter on the given object.
      */
     public static void set(Object target, Method setter, Object value) {
         if (target == null || setter == null)
             return;
         makeAccessible(setter, setter.getModifiers());
         try {
             setter.invoke(target, new Object[] { value });
         } catch (Throwable t) {
             throw wrapReflectionException(t);
         }
     }

     /**
      * Invoke the given setter on the given object.
      */
     public static void set(Object target, Method setter, boolean value) {
         set(target, setter, (value) ? Boolean.TRUE : Boolean.FALSE);
     }

     /**
      * Invoke the given setter on the given object.
      */
     public static void set(Object target, Method setter, byte value) {
         set(target, setter, new Byte(value));
     }

     /**
      * Invoke the given setter on the given object.
      */
     public static void set(Object target, Method setter, char value) {
         set(target, setter, new Character(value));
     }

     /**
      * Invoke the given setter on the given object.
      */
     public static void set(Object target, Method setter, double value) {
         set(target, setter, new Double(value));
     }

     /**
      * Invoke the given setter on the given object.
      */
     public static void set(Object target, Method setter, float value) {
         set(target, setter, new Float(value));
     }

     /**
      * Invoke the given setter on the given object.
      */
     public static void set(Object target, Method setter, int value) {
         set(target, setter, new Integer(value));
     }

     /**
      * Invoke the given setter on the given object.
      */
     public static void set(Object target, Method setter, long value) {
         set(target, setter, new Long(value));
     }

     /**
      * Invoke the given setter on the given object.
      */
     public static void set(Object target, Method setter, short value) {
         set(target, setter, new Short(value));
     }
 }
	/*
	* 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.openjpa.enhance;

	import java.lang.reflect.AccessibleObject;
	import java.lang.reflect.Field;
	import java.lang.reflect.InvocationTargetException;
	import java.lang.reflect.Method;
	import java.lang.reflect.Modifier;
	import java.security.AccessController;

	import org.apache.commons.lang.StringUtils;
	import org.apache.openjpa.lib.util.J2DoPrivHelper;
	import org.apache.openjpa.lib.util.Localizer;
	import org.apache.openjpa.util.GeneralException;
	import org.apache.openjpa.util.UserException;

	/**
	* Reflection utilities used to support and augment enhancement. Used both
	* at enhancement time and at runtime.
	*
	* @author Abe White
	*/
	public class Reflection {

	private static final Localizer _loc = Localizer.forPackage
	(Reflection.class);

	/**
	* Return the getter method matching the given property name, optionally
	* throwing an exception if none.
	*/
	public static Method findGetter(Class cls, String prop, boolean mustExist) {
	prop = StringUtils.capitalize(prop);
	String name = "get" + prop;
	Method m;
	try {
	// this algorithm searches for a get<prop> or is<prop> method in
	// a breadth-first manner.
	for (Class c = cls; c != null && c != Object.class;
	c = c.getSuperclass()) {
	m = getDeclaredMethod(c, name, null);
	if (m != null) {
	return m;
	} else {
	m = getDeclaredMethod(c, "is" + prop, null);
	if (m != null && (m.getReturnType() == boolean.class
	\|\| m.getReturnType() == Boolean.class))
	return m;
	}
	}
	} catch (Exception e) {
	throw new GeneralException(e);
	}

	if (mustExist)
	throw new UserException(_loc.get("bad-getter", cls, prop));
	return null;
	}

	/**
	* Return the setter method matching the given property name, optionally
	* throwing an exception if none. The property must also have a getter.
	*/
	public static Method findSetter(Class cls, String prop, boolean mustExist) {
	Method getter = findGetter(cls, prop, mustExist);
	return (getter == null) ? null
	: findSetter(cls, prop, getter.getReturnType(), mustExist);
	}

	/**
	* Return the setter method matching the given property name, optionally
	* throwing an exception if none.
	*/
	public static Method findSetter(Class cls, String prop, Class param,
	boolean mustExist) {
	String name = "set" + StringUtils.capitalize(prop);
	Method m;
	try {
	for (Class c = cls; c != null && c != Object.class;
	c = c.getSuperclass()) {
	m = getDeclaredMethod(c, name, param);
	if (m != null)
	return m;
	}
	} catch (Exception e) {
	throw new GeneralException(e);
	}

	if (mustExist)
	throw new UserException(_loc.get("bad-setter", cls, prop));
	return null;
	}

	/**
	* Invokes <code>cls.getDeclaredMethods()</code>, and returns the method
	* that matches the <code>name</code> and <code>param</code> arguments.
	* Avoids the exception thrown by <code>Class.getDeclaredMethod()</code>
	* for performance reasons. <code>param</code> may be null. Additionally,
	* if there are multiple methods with different return types, this will
	* return the method defined in the least-derived class.
	*
	* @since 0.9.8
	*/
	static Method getDeclaredMethod(Class cls, String name,
	Class param) {
	Method[] methods = (Method[]) AccessController.doPrivileged(
	J2DoPrivHelper.getDeclaredMethodsAction(cls));
	Method candidate = null;
	for (int i = 0 ; i < methods.length; i++) {
	if (name.equals(methods[i].getName())) {
	Class[] methodParams = methods[i].getParameterTypes();
	if (param == null && methodParams.length == 0)
	candidate = mostDerived(methods[i], candidate);
	else if (param != null && methodParams.length == 1
	&& param.equals(methodParams[0]))
	candidate = mostDerived(methods[i], candidate);
	}
	}
	return candidate;
	}

	static Method mostDerived(Method meth1, Method meth2) {
	if (meth1 == null)
	return meth2;
	if (meth2 == null)
	return meth1;

	Class cls2 = meth2.getDeclaringClass();
	Class cls1 = meth1.getDeclaringClass();

	if (cls1.equals(cls2)) {
	Class ret1 = meth1.getReturnType();
	Class ret2 = meth2.getReturnType();
	if (ret1.isAssignableFrom(ret2))
	return meth2;
	else if (ret2.isAssignableFrom(ret1))
	return meth1;
	else
	throw new IllegalArgumentException(
	_loc.get("most-derived-unrelated-same-type", meth1, meth2)
	.getMessage());
	} else {
	if (cls1.isAssignableFrom(cls2))
	return meth2;
	else if (cls2.isAssignableFrom(cls1))
	return meth1;
	else
	throw new IllegalArgumentException(
	_loc.get("most-derived-unrelated", meth1, meth2)
	.getMessage());
	}
	}

	/**
	* Return the field with the given name, optionally throwing an exception
	* if none.
	*/
	public static Field findField(Class cls, String name, boolean mustExist) {
	try {
	Field f;
	for (Class c = cls; c != null && c != Object.class;
	c = c.getSuperclass()) {
	f = getDeclaredField(c, name);
	if (f != null)
	return f;
	}
	} catch (Exception e) {
	throw new GeneralException(e);
	}

	if (mustExist)
	throw new UserException(_loc.get("bad-field", cls, name));
	return null;
	}

	/**
	* Invokes <code>cls.getDeclaredFields()</code>, and returns the field
	* that matches the <code>name</code> argument. Avoids the exception
	* thrown by <code>Class.getDeclaredField()</code> for performance reasons.
	*
	* @since 0.9.8
	*/
	private static Field getDeclaredField(Class cls, String name) {
	Field[] fields = (Field[]) AccessController.doPrivileged(
	J2DoPrivHelper.getDeclaredFieldsAction(cls));
	for (int i = 0 ; i < fields.length; i++) {
	if (name.equals(fields[i].getName()))
	return fields[i];
	}
	return null;
	}

	/**
	* Return the value of the given field in the given object.
	*/
	public static Object get(Object target, Field field) {
	if (target == null \|\| field == null)
	return null;
	makeAccessible(field, field.getModifiers());
	try {
	return field.get(target);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Get the value of the given named field or a corresponding getter method.
	*
	* @return null if the field does not exist and mustExist is set to false or
	* the given target is null.
	*
	* @exception UserException if mustExist is true and the field or getter
	* method is non-existent
	*/
	public static Object getValue(Object obj, String prop, boolean mustExist) {
	if (obj == null)
	return null;
	Class cls = obj.getClass();
	Field field = findField(cls, prop, false);
	if (field != null)
	return get(obj, field);
	Method getter = findGetter(cls, prop, false);
	if (getter != null)
	return get(obj, getter);
	if (mustExist)
	throw new UserException(_loc.get("bad-field", cls, prop));
	return null; // should not reach
	}

	/**
	* Make the given member accessible if it isn't already.
	*/
	private static void makeAccessible(AccessibleObject ao, int mods) {
	try {
	if (!Modifier.isPublic(mods) && !ao.isAccessible())
	AccessController.doPrivileged(J2DoPrivHelper
	.setAccessibleAction(ao, true));
	} catch (SecurityException se) {
	throw new UserException(_loc.get("reflect-security", ao)).
	setFatal(true);
	}
	}

	/**
	* Wrap the given reflection exception as a runtime exception.
	*/
	private static RuntimeException wrapReflectionException(Throwable t) {
	if (t instanceof InvocationTargetException)
	t = ((InvocationTargetException) t).getTargetException();
	if (t instanceof RuntimeException)
	return (RuntimeException) t;
	return new GeneralException(t);
	}

	/**
	* Return the value of the given field in the given object.
	*/
	public static boolean getBoolean(Object target, Field field) {
	if (target == null \|\| field == null)
	return false;
	makeAccessible(field, field.getModifiers());
	try {
	return field.getBoolean(target);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Return the value of the given field in the given object.
	*/
	public static byte getByte(Object target, Field field) {
	if (target == null \|\| field == null)
	return (byte) 0;
	makeAccessible(field, field.getModifiers());
	try {
	return field.getByte(target);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Return the value of the given field in the given object.
	*/
	public static char getChar(Object target, Field field) {
	if (target == null \|\| field == null)
	return (char) 0;
	makeAccessible(field, field.getModifiers());
	try {
	return field.getChar(target);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Return the value of the given field in the given object.
	*/
	public static double getDouble(Object target, Field field) {
	if (target == null \|\| field == null)
	return 0D;
	makeAccessible(field, field.getModifiers());
	try {
	return field.getDouble(target);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Return the value of the given field in the given object.
	*/
	public static float getFloat(Object target, Field field) {
	if (target == null \|\| field == null)
	return 0F;
	makeAccessible(field, field.getModifiers());
	try {
	return field.getFloat(target);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Return the value of the given field in the given object.
	*/
	public static int getInt(Object target, Field field) {
	if (target == null \|\| field == null)
	return 0;
	makeAccessible(field, field.getModifiers());
	try {
	return field.getInt(target);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Return the value of the given field in the given object.
	*/
	public static long getLong(Object target, Field field) {
	if (target == null \|\| field == null)
	return 0L;
	makeAccessible(field, field.getModifiers());
	try {
	return field.getLong(target);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Return the value of the given field in the given object.
	*/
	public static short getShort(Object target, Field field) {
	if (target == null \|\| field == null)
	return (short) 0;
	makeAccessible(field, field.getModifiers());
	try {
	return field.getShort(target);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Return the return value of the given getter in the given object.
	*/
	public static Object get(Object target, Method getter) {
	if (target == null \|\| getter == null)
	return null;
	makeAccessible(getter, getter.getModifiers());
	try {
	return getter.invoke(target, (Object[]) null);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Return the return value of the given getter in the given object.
	*/
	public static boolean getBoolean(Object target, Method getter) {
	Object o = get(target, getter);
	return (o == null) ? false : ((Boolean) o).booleanValue();
	}

	/**
	* Return the return value of the given getter in the given object.
	*/
	public static byte getByte(Object target, Method getter) {
	Object o = get(target, getter);
	return (o == null) ? (byte) 0 : ((Number) o).byteValue();
	}

	/**
	* Return the return value of the given getter in the given object.
	*/
	public static char getChar(Object target, Method getter) {
	Object o = get(target, getter);
	return (o == null) ? (char) 0 : ((Character) o).charValue();
	}

	/**
	* Return the return value of the given getter in the given object.
	*/
	public static double getDouble(Object target, Method getter) {
	Object o = get(target, getter);
	return (o == null) ? 0D : ((Number) o).doubleValue();
	}

	/**
	* Return the return value of the given getter in the given object.
	*/
	public static float getFloat(Object target, Method getter) {
	Object o = get(target, getter);
	return (o == null) ? 0F : ((Number) o).floatValue();
	}

	/**
	* Return the return value of the given getter in the given object.
	*/
	public static int getInt(Object target, Method getter) {
	Object o = get(target, getter);
	return (o == null) ? 0 : ((Number) o).intValue();
	}

	/**
	* Return the return value of the given getter in the given object.
	*/
	public static long getLong(Object target, Method getter) {
	Object o = get(target, getter);
	return (o == null) ? 0L : ((Number) o).longValue();
	}

	/**
	* Return the return value of the given getter in the given object.
	*/
	public static short getShort(Object target, Method getter) {
	Object o = get(target, getter);
	return (o == null) ? (short) 0 : ((Number) o).shortValue();
	}

	/**
	* Set the value of the given field in the given object.
	*/
	public static void set(Object target, Field field, Object value) {
	if (target == null \|\| field == null)
	return;
	makeAccessible(field, field.getModifiers());
	try {
	field.set(target, value);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Set the value of the given field in the given object.
	*/
	public static void set(Object target, Field field, boolean value) {
	if (target == null \|\| field == null)
	return;
	makeAccessible(field, field.getModifiers());
	try {
	field.setBoolean(target, value);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Set the value of the given field in the given object.
	*/
	public static void set(Object target, Field field, byte value) {
	if (target == null \|\| field == null)
	return;
	makeAccessible(field, field.getModifiers());
	try {
	field.setByte(target, value);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Set the value of the given field in the given object.
	*/
	public static void set(Object target, Field field, char value) {
	if (target == null \|\| field == null)
	return;
	makeAccessible(field, field.getModifiers());
	try {
	field.setChar(target, value);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Set the value of the given field in the given object.
	*/
	public static void set(Object target, Field field, double value) {
	if (target == null \|\| field == null)
	return;
	makeAccessible(field, field.getModifiers());
	try {
	field.setDouble(target, value);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Set the value of the given field in the given object.
	*/
	public static void set(Object target, Field field, float value) {
	if (target == null \|\| field == null)
	return;
	makeAccessible(field, field.getModifiers());
	try {
	field.setFloat(target, value);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Set the value of the given field in the given object.
	*/
	public static void set(Object target, Field field, int value) {
	if (target == null \|\| field == null)
	return;
	makeAccessible(field, field.getModifiers());
	try {
	field.setInt(target, value);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Set the value of the given field in the given object.
	*/
	public static void set(Object target, Field field, long value) {
	if (target == null \|\| field == null)
	return;
	makeAccessible(field, field.getModifiers());
	try {
	field.setLong(target, value);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Set the value of the given field in the given object.
	*/
	public static void set(Object target, Field field, short value) {
	if (target == null \|\| field == null)
	return;
	makeAccessible(field, field.getModifiers());
	try {
	field.setShort(target, value);
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Set the value of the given field in the given object.
	* Same behavior as above methods, but parameter ordering is rearranged
	* to simplify usage from generated bytecodes.
	*
	* @since 1.0.0
	*/
	public static void set(Object target, Object value, Field field) {
	set(target, field, value);
	}

	/**
	* Set the value of the given field in the given object.
	* Same behavior as above methods, but parameter ordering is rearranged
	* to simplify usage from generated bytecodes.
	*
	* @since 1.0.0
	*/
	public static void set(Object target, boolean value, Field field) {
	set(target, field, value);
	}

	/**
	* Set the value of the given field in the given object.
	* Same behavior as above methods, but parameter ordering is rearranged
	* to simplify usage from generated bytecodes.
	*
	* @since 1.0.0
	*/
	public static void set(Object target, byte value, Field field) {
	set(target, field, value);
	}

	/**
	* Set the value of the given field in the given object.
	* Same behavior as above methods, but parameter ordering is rearranged
	* to simplify usage from generated bytecodes.
	*
	* @since 1.0.0
	*/
	public static void set(Object target, char value, Field field) {
	set(target, field, value);
	}

	/**
	* Set the value of the given field in the given object.
	* Same behavior as above methods, but parameter ordering is rearranged
	* to simplify usage from generated bytecodes.
	*
	* @since 1.0.0
	*/
	public static void set(Object target, double value, Field field) {
	set(target, field, value);
	}

	/**
	* Set the value of the given field in the given object.
	* Same behavior as above methods, but parameter ordering is rearranged
	* to simplify usage from generated bytecodes.
	*
	* @since 1.0.0
	*/
	public static void set(Object target, float value, Field field) {
	set(target, field, value);
	}

	/**
	* Set the value of the given field in the given object.
	* Same behavior as above methods, but parameter ordering is rearranged
	* to simplify usage from generated bytecodes.
	*
	* @since 1.0.0
	*/
	public static void set(Object target, int value, Field field) {
	set(target, field, value);
	}

	/**
	* Set the value of the given field in the given object.
	* Same behavior as above methods, but parameter ordering is rearranged
	* to simplify usage from generated bytecodes.
	*
	* @since 1.0.0
	*/
	public static void set(Object target, long value, Field field) {
	set(target, field, value);
	}

	/**
	* Set the value of the given field in the given object.
	* Same behavior as above methods, but parameter ordering is rearranged
	* to simplify usage from generated bytecodes.
	*
	* @since 1.0.0
	*/
	public static void set(Object target, short value, Field field) {
	set(target, field, value);
	}

	/**
	* Invoke the given setter on the given object.
	*/
	public static void set(Object target, Method setter, Object value) {
	if (target == null \|\| setter == null)
	return;
	makeAccessible(setter, setter.getModifiers());
	try {
	setter.invoke(target, new Object[] { value });
	} catch (Throwable t) {
	throw wrapReflectionException(t);
	}
	}

	/**
	* Invoke the given setter on the given object.
	*/
	public static void set(Object target, Method setter, boolean value) {
	set(target, setter, (value) ? Boolean.TRUE : Boolean.FALSE);
	}

	/**
	* Invoke the given setter on the given object.
	*/
	public static void set(Object target, Method setter, byte value) {
	set(target, setter, new Byte(value));
	}

	/**
	* Invoke the given setter on the given object.
	*/
	public static void set(Object target, Method setter, char value) {
	set(target, setter, new Character(value));
	}

	/**
	* Invoke the given setter on the given object.
	*/
	public static void set(Object target, Method setter, double value) {
	set(target, setter, new Double(value));
	}

	/**
	* Invoke the given setter on the given object.
	*/
	public static void set(Object target, Method setter, float value) {
	set(target, setter, new Float(value));
	}

	/**
	* Invoke the given setter on the given object.
	*/
	public static void set(Object target, Method setter, int value) {
	set(target, setter, new Integer(value));
	}

	/**
	* Invoke the given setter on the given object.
	*/
	public static void set(Object target, Method setter, long value) {
	set(target, setter, new Long(value));
	}

	/**
	* Invoke the given setter on the given object.
	*/
	public static void set(Object target, Method setter, short value) {
	set(target, setter, new Short(value));
	}
	}