Here you can find the source of findField(String fieldName, Class> type)
private static Field findField(String fieldName, Class<?> type)
//package com.java2s; /*//from w ww.j av a2s . co m * Copyright 2010-2019 the original author or authors. * * 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 * * https://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 { private static Field findField(String fieldName, Object target) { return findField(fieldName, target.getClass()); } private static Field findField(String fieldName, Class<?> type) { Field field = null; while (field == null && !type.equals(Object.class)) { try { field = type.getDeclaredField(fieldName); } catch (Throwable ignore) { } finally { type = type.getSuperclass(); } } return field; } }