arthas使用方法

arthas是阿里开发的一个java诊断工具，官网

https://arthas.aliyun.com/zh-cn/

下载地址

https://github.com/alibaba/arthas/releases

首先启动arthas-boot.jar，并选择java程序的pid

java -jar ./arthas-boot.jar
[INFO] arthas-boot version: 3.6.0
[INFO] Found existing java process, please choose one and input the serial number of the process, eg : 1. Then hit ENTER.
* [1]: 23235
  [2]: 66309 math-game.jar
  [3]: 78485
  [4]: 85979
  [5]: 16061 org.jd.gui.OsxApp
  [6]: 90607 org.jetbrains.jps.cmdline.Launcher
  [7]: 88623
2
[INFO] arthas home: /Users/lintong/Downloads/arthas-bin
[INFO] Try to attach process 66309
[INFO] Attach process 66309 success.
[INFO] arthas-client connect 127.0.0.1 3658
  ,---.  ,------. ,--------.,--.  ,--.  ,---.   ,---.
 /  O  \ |  .--. ''--.  .--'|  '--'  | /  O  \ '   .-'
|  .-.  ||  '--'.'   |  |   |  .--.  ||  .-.  |`.  `-.
|  | |  ||  |\  \    |  |   |  |  |  ||  | |  |.-'    |
`--' `--'`--' '--'   `--'   `--'  `--'`--' `--'`-----'

wiki       https://arthas.aliyun.com/doc
tutorials  https://arthas.aliyun.com/doc/arthas-tutorials.html
version    3.6.0
main_class demo.MathGame
pid        66309
time       2022-04-10 17:08:50

[arthas@66309]$

1.查看仪表盘

输入dashboard，退出control+C

2.查看主线程

[arthas@66309]$ thread 1
"main" Id=1 TIMED_WAITING
    at java.lang.Thread.sleep(Native Method)
    at java.lang.Thread.sleep(Thread.java:340)
    at java.util.concurrent.TimeUnit.sleep(TimeUnit.java:386)
    at demo.MathGame.main(MathGame.java:17)

3.watch命令监控方法

监控返回值

watch demo.MathGame primeFactors returnObj
Press Q or Ctrl+C to abort.
Affect(class count: 1 , method count: 1) cost in 119 ms, listenerId: 1
method=demo.MathGame.primeFactors location=AtExit
ts=2022-04-10 17:16:30; [cost=1.662911ms] result=@ArrayList[
    @Integer[2],
    @Integer[2],
    @Integer[2],
    @Integer[2],
    @Integer[2],
    @Integer[2],
    @Integer[2],
    @Integer[3],
    @Integer[419],
]

监控参数值

watch demo.MathGame primeFactors params
Press Q or Ctrl+C to abort.
Affect(class count: 1 , method count: 1) cost in 23 ms, listenerId: 2
method=demo.MathGame.primeFactors location=AtExceptionExit
ts=2022-04-10 17:16:44; [cost=0.266471ms] result=@Object[][
    @Integer[-150713],
]

4.反编译

jad demo.MathGame

其他参考：https://arthas.aliyun.com/doc/advanced-use.html

arthas使用方法

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