只要涉及到精准计算,一定先清理一下垃圾【gc()】
public static void main(String[] args) {Runtime r = Runtime.getRuntime();r.gc();//计算内存前先垃圾回收一次long start = System.currentTimeMillis();//开始Timelong startMem = r.freeMemory(); // 开始Memorynew String("1");//!!!!!被测的程序!!!!!long endMem =r.freeMemory(); // 末尾Memorylong end = System.currentTimeMillis();//末尾Time//输出System.out.println("用时消耗: "+String.valueOf(end - start)+"ms");System.out.println("内存消耗: "+String.valueOf((startMem- endMem)/1024)+"KB");}