Here you can find the source of compareTo(List
static public <T extends Comparable<T>> int compareTo(List<T> list, int i, int j)
//package com.java2s; /**//w w w . j a va2 s . com * Copyright 2014, Emory University * * 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.util.List; public class Main { static public <T extends Comparable<T>> int compareTo(List<T> list, int i, int j) { return list.get(i).compareTo(list.get(j)); } }