Memory Analyzer分析記憶體洩漏

模拟一次記憶體溢出

1. 程式不斷地向ArrayList添加對象，直至溢出

public class User {
    String userName;
    String passWord;

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPassWord() {
        return passWord;
    }

    public void setPassWord(String passWord) {
        this.passWord = passWord;
    }
}
           

import java.util.ArrayList;
import java.util.List;

public class jvmMemoryOut {

    public static void main(String[] args) {
        List<Object> listObject = new ArrayList<>();
        for (int i = 0; i < 100000; i++) {
            System.out.println("i:" + i);
            User user = new User();
            user.setUserName("小明");
            user.setPassWord("123456");
            listObject.add(user);
        }
        System.out.println("添加成功...");
    }
}
           

1. VM設定

-Xms1m -Xmx2m -XX:+PrintGCDetails -XX:+HeapDumpOnOutOfMemoryError -XX:HeapDumpPath=C:\Users\0096001939\Desktop\dump
           

3. 運作後獲得dump檔案

Memory Analyzer打開dump檔案

1. 檢視到概覽，然後我們打開details

   

2. 通過details我們看到多個user在一個list中，撐爆了記憶體

   

3. 檢視user所線上程的詳情.