Retrieves all fields from the class, including its super classes. - Java Reflection

Java examples for Reflection:Field

  1. HOME
  2. Java
  3. Reflection
  4. Field

Description

Retrieves all fields from the class, including its super classes.

Demo Code

/**//  w w w .j  a v a2  s  . c  o  m
 * Copyright (C) 2011  JTalks.org Team
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 */
//package com.java2s;

import java.lang.reflect.Field;
import java.lang.reflect.Modifier;
import java.util.ArrayList;

import java.util.List;

public class Main {
    public static void main(String[] argv) throws Exception {
        Class beanClass = String.class;
        System.out.println(getAllFields(beanClass));
    }

    /**
     * Retrieves all fields from the class, including its super classes. <br>
     * 
     * <i>Leaves out all static fields.</i>
     * 
     * @param beanClass class whose fields will be extracted
     * @return list of extracted fields
     */
    public static List<Field> getAllFields(Class<?> beanClass) {
        List<Class<?>> allClasses = getClassHierarchy(beanClass);

        List<Field> fields = new ArrayList<Field>();

        for (Class<?> current : allClasses) {
            for (Field field : current.getDeclaredFields()) {
                if (!Modifier.isStatic(field.getModifiers())) {
                    fields.add(field);
                }
            }
        }

        return fields;
    }

    /**
     * Creates all class hierarchy from the given class to Object,
     * <b>exclusive</b>, i.e. Object won't go to the list). Interfaces won't be
     * listed in the result.
     * 
     * @param beanClass class for building its hierarchy
     * @return list of all classes from the given class up to {@link Object}
     */
    public static List<Class<?>> getClassHierarchy(Class<?> beanClass) {
        List<Class<?>> classes = new ArrayList<Class<?>>();

        Class<?> current = beanClass;
        while (current != Object.class) {
            classes.add(current);
            current = current.getSuperclass();
        }

        return classes;
    }
}

Related Tutorials