Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright (C) 2002-2015 FlyMine
 *
 * This code may be freely distributed and modified under the
 * terms of the GNU Lesser General Public Licence.  This should
 * be distributed with the code.  See the LICENSE file for more
 * information or http://www.gnu.org/copyleft/lesser.html.
 *
 */

import java.util.ArrayList;
import java.util.Collection;

import java.util.HashMap;
import java.util.HashSet;

import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.Stack;

public class Main {
    /**
     * Sorts objects in the given collection into different types by Class.
     * @param <E> the element type
     * @param objects a Collection of objects
     * @param inherit if true, objects are put into all their class's superclasses as well, except
     * Object - the original Collection can be used in that case
     * @return a Map from Class to List of objects in that class
     */
    public static <E> Map<Class<?>, List<E>> groupByClass(Collection<E> objects, boolean inherit) {
        Map<Class<?>, List<E>> retval = new HashMap<Class<?>, List<E>>();
        for (E o : objects) {
            Class<?> c = o.getClass();
            if (inherit) {
                Set<Class<?>> done = new HashSet<Class<?>>();
                done.add(Object.class);
                Stack<Class<?>> todo = new Stack<Class<?>>();
                todo.push(c);
                while (!todo.empty()) {
                    c = todo.pop();
                    if ((c != null) && !done.contains(c)) {
                        done.add(c);
                        List<E> l = retval.get(c);
                        if (l == null) {
                            l = new ArrayList<E>();
                            retval.put(c, l);
                        }
                        l.add(o);
                        todo.push(c.getSuperclass());
                        Class<?>[] classes = c.getInterfaces();
                        for (int i = 0; i < classes.length; i++) {
                            todo.push(classes[i]);
                        }
                    }
                }
            } else {
                List<E> l = retval.get(c);
                if (l == null) {
                    l = new ArrayList<E>();
                    retval.put(c, l);
                }
                l.add(o);
            }
        }
        return retval;
    }
}