1. 程式人生 > >jvm虛擬機器組成部分講解、jvm虛擬機器引數使用講解併發程式設計框架篇

jvm虛擬機器組成部分講解、jvm虛擬機器引數使用講解併發程式設計框架篇

package com.bjsxt.base001;


public class Test01 {

	public static void main(String[] args) {

		//-Xms5m -Xmx20m -XX:+PrintGCDetails -XX:+UseSerialGC -XX:+PrintCommandLineFlags
		
		//檢視GC資訊
		System.out.println("max memory:" + Runtime.getRuntime().maxMemory());
		System.out.println("free memory:" + Runtime.getRuntime().freeMemory());
		System.out.println("total memory:" + Runtime.getRuntime().totalMemory());
		
		byte[] b1 = new byte[1*1024*1024];
		System.out.println("分配了1M");
		System.out.println("max memory:" + Runtime.getRuntime().maxMemory());
		System.out.println("free memory:" + Runtime.getRuntime().freeMemory());
		System.out.println("total memory:" + Runtime.getRuntime().totalMemory());
		
		byte[] b2 = new byte[4*1024*1024];
		System.out.println("分配了4M");
		System.out.println("max memory:" + Runtime.getRuntime().maxMemory());
		System.out.println("free memory:" + Runtime.getRuntime().freeMemory());
		System.out.println("total memory:" + Runtime.getRuntime().totalMemory());
		
	}
	
}