Here you can find the source of setFieldValue(final Object obj, final String fieldName, final Object value)
public static void setFieldValue(final Object obj, final String fieldName, final Object value)
//package com.java2s; /*//w w w . j a va2s. c o m * 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. */ import java.lang.reflect.Field; public class Main { public static void setFieldValue(final Object obj, final String fieldName, final Object value) { getSetField(obj, fieldName, false, value); } private static Object getSetField(final Object obj, final String fieldName, final boolean isGet, final Object value) { Class<?> clazz = obj.getClass(); while (clazz != null) { try { final Field field = clazz.getDeclaredField(fieldName); field.setAccessible(true); if (isGet) { return field.get(obj); } else { field.set(obj, value); return null; } } catch (final Exception ignore) { // ignore } clazz = clazz.getSuperclass(); } throw new RuntimeException("Field " + fieldName + " not found on object " + obj); } }