Java使用JVM堆外記憶體
阿新 • • 發佈:2019-01-05
package com.company; import sun.misc.Unsafe; /** * Created by yellowboy on 2017/3/9. */ public class Main3 { public static void main(String[] args) throws Exception { Integer[] a = new Integer[]{1, 2, 3, 4, 5, 7, 9, 888, 8, 102};//給定一個整形陣列 final int length = a.length ; final Unsafe unsafe = UnsafeUtil.getUnsafe();//獲取unsafe物件用於分配記憶體 final long addr[] = new long[length];//定義addr陣列記錄整形陣列每個值儲存的位置 try { for(int i = 0 ;i < length ; i++ ) { addr[i] = unsafe.allocateMemory(Integer.SIZE);//分配一個Integer的大小的記憶體 unsafe.putInt(addr[i],a[i]);//把數字放在地址空間上 } a = null; for(int i = 0 ;i < length ; i++ ) { System.out.println(unsafe.getInt(addr[i]));//輸出每個地址空間的值 } } finally { for(int i = 0 ;i < length ; i++ ) { unsafe.freeMemory(addr[i]);//釋放每個地址空間 } } } }