Java Reflection Field Set setField(Object owner, String targetClass, String fieldName, Object value)

Description

Set object's field with custom value even it's private.

License

Apache License

Parameter

Parameter	Description
owner	: target object
classLevel	: 0 means itself, 1 means it's father, and so on...
fieldName	: name of the target field
value	: new value of the target field

Exception

Parameter	Description
NoSuchFieldException	an exception
SecurityException	an exception
IllegalAccessException	an exception
IllegalArgumentException	an exception

Declaration

public static void setField(Object owner, String targetClass, String fieldName, Object value)
        throws SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException 

Method Source Code

//package com.java2s;
/*/*from   ww  w . j a  v  a 2 s  . c  om*/
 * Copyright (C) 2011 Baidu.com Inc
 *
 * 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.
 */

import java.lang.reflect.Field;

public class Main {
    /**
     * Set object's field with custom value even it's private.
     * 
     * @param owner
     *            : target object
     * @param classLevel
     *            : 0 means itself, 1 means it's father, and so on...
     * @param fieldName
     *            : name of the target field
     * @param value
     *            : new value of the target field
     * @throws NoSuchFieldException
     * @throws SecurityException
     * @throws IllegalAccessException
     * @throws IllegalArgumentException
     */
    public static void setField(Object owner, String targetClass, String fieldName, Object value)
            throws SecurityException, NoSuchFieldException, IllegalArgumentException, IllegalAccessException {
        Class<?> ownerclass = getTargetclass(owner, targetClass);
        Field field = ownerclass.getDeclaredField(fieldName);
        if (!field.isAccessible()) {
            field.setAccessible(true);
        }
        field.set(owner, value);
    }

    private static Class<?> getTargetclass(Object owner, String targetClass) {
        try {
            return null == targetClass ? owner.getClass() : Class.forName(targetClass);
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
        return null;
    }
}

Related

1. setField(Object object, String fieldName, Object value)
2. setField(Object object, String name, boolean value)
3. setField(Object object, String name, Object value)
4. setField(Object object, String name, Object value)
5. setField(Object owner, String name, Object newValue, Class definedIn)
6. setField(Object service, String name, Object obj)
7. setField(Object source, String fieldName, Object value)
8. setField(Object sourceObj, Object targetObj, Field valueField, List targetFields)
9. setField(Object target, Field field, Object value)