Here you can find the source of getFreeMemoryMB()
public static long getFreeMemoryMB()
//package com.java2s; /**/*from w w w . j a v a 2 s .c o m*/ * Copyright 2011 Pablo Mendes, Max Jakob * * 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. */ public class Main { public static long getFreeMemoryMB() { long freeMemBytes = Runtime.getRuntime().freeMemory(); return freeMemBytes / (1024 * 1024); } }