Java-debug-tool is a dynamic debugging tool. it provides some debugging commands to debug your code in runtime.
new features / bug fix / code clean / etc.
- java 8 + , java 7 support is on the way ...
- Unix like OS
- libc
wget https://github.com/pandening/storm-ml/releases/download/8.0/javadebug-tool-install.sh
sh javadebug-tool-install.sh./javadebug-agent-launch.sh pid@ip:port
./javadebug-agent-launch.sh pid@ip
./javadebug-agent-launch.sh pidthe default port is 11234.
./javadebug-client-launch.sh
./javadebug-client-launch.sh ip:portJava-debug-tool including 2-part ability, debugging and profiling.
debug your code in runtime, the main command list :
- mt (method trace)
- fc (find class)
the simplest usage of 'mt' command like this :
mt -c [class name with package] -m [method name]
there are many other options for mt command:
- timeout : set command execute timeout (seconds unit)
- t : the debug event type
- return : stop debug when method exit
- throw : stop debug when method throw exception
-
e ： the target exception class name [with package] -
tl : set the target invoked line, ref [line] -
te : set the target line's expression ref [line]
-
- watch : stop debug when the params match
-
i : the spring expression -
tl : set the target invoked line, ref [line] -
te : set the target line's expression ref [line]
-
- custom : call method & debug itself
-
i : the params -
tl : set the target invoked line, ref [line] -
te : set the target line's expression ref [line]
-
- line : stop debug when special line is invoked(and the spring expression is true).
-
tl : set the target invoked line -
te : set the target line's expression
-
- record : record some method calls
-
u : show the record method call with index [from 0 inc] -
n : the record count limit -
time : timeout for recording
-
- l : just show the target line's debug info
for 'fc' command, it's very easy to use:
[case 1] you know the class name and want to find the class
fc -class [class name]
[case 2] you just want to find some classes by the regex
fc -r [regex to match class]
the 'l' option can set the output class limit. like this:
fc -r regex -l 10
java-debug-tool can profiling your code, there are some command can get the performance data in run time;
- thread
- monitor
- cputime
the thread command can get the cpu usage of each thread, and the call stack, and you can get the topN busy thread by this command:
thread command options:
- top : [topN] get the topN busy thread info
- status : [R(runnable)|W(waiting)|TW(timed waiting)|B(blocking)] get the target status' thread info
- tid : [thread id] get the thread info by thread id
monitor (aka collect) command options :
- t : the monitor event type, multi type can split with ',' like thread,mem
- thread : the thread statistic info
- mem : the mem info
- class : the class info
- gc : the gc info
- i : the interval (secs)
the default event is thread, the default interval is 5 seconds
the cputime command can get the cpu usage of the target jvm, the interval is 30 seconds, the base usage of this command is :
ct -o csv
the 'o' option set the output format, you can set one from [csv,json]; the csv format is recommend, you need to wait 30 seconds before the command execute successfully. the output like this:
---------------------------------------------------------------------------------------------
Command ：ct
Round ：1
ClientId ：10000
ClientType ：console:1
Version ：version:1
CommandCost ：32125 (ms)
STW_Cost ：0 (ms)
Time: : Mon Feb 03 17:33:10 CST 2020
---------------------------------------------------------------------------------------------
Start Time : Mon Feb 03 17:32:38 CST 2020
Stop Time : Mon Feb 03 17:33:10 CST 2020
Total cpu usage : 35.425249999999984 ms
time;usr_ms;sys_ms;avg_usr_ms;avg_sys_ms;nivc_switch_per_sec;nvc_switch_per_sec
0;22.729;13.790;20.770;14.655;514;11
1;18.769;11.816;20.770;14.655;499;18
2;19.048;12.215;20.770;14.655;483;13
3;22.882;14.352;20.770;14.655;483;9
4;49.963;17.214;20.770;14.655;479;18
5;23.305;15.979;20.770;14.655;456;16
6;22.382;13.520;20.770;14.655;491;8
7;25.801;11.920;20.770;14.655;543;7
8;18.927;12.211;20.770;14.655;509;14
9;22.440;9.026;20.770;14.655;541;6
10;20.290;13.212;20.770;14.655;472;13
11;19.866;15.524;20.770;14.655;456;5
12;24.528;16.648;20.770;14.655;447;19
13;19.002;16.981;20.770;14.655;457;11
14;20.882;16.202;20.770;14.655;452;15
15;20.041;15.652;20.770;14.655;484;16
16;17.661;10.187;20.770;14.655;507;4
17;15.381;10.135;20.770;14.655;498;12
18;18.671;16.080;20.770;14.655;446;13
19;27.149;17.041;20.770;14.655;481;14
20;18.231;13.681;20.770;14.655;502;14
21;17.777;13.696;20.770;14.655;480;12
22;18.266;16.266;20.770;14.655;450;17
23;20.510;16.447;20.770;14.655;480;13
24;19.699;16.250;20.770;14.655;474;14
25;19.966;15.105;20.770;14.655;455;24
26;25.839;15.825;20.770;14.655;447;15
27;19.736;16.556;20.770;14.655;455;17
28;18.673;16.246;20.770;14.655;440;18
29;18.499;16.801;20.770;14.655;447;16
---------------------------------------------------------------------------------------------
- time : the time line
- usr_ms : user time mills
- sys_ms : system time mills
- avg_usr_ms : the avg user time mills
- avg_sys_ms : the avg system time mills
- nivc_switch_per_sec : the nivc switch per sec
- nvc_switch_per_sec ：the nvc switch per sec
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val |
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|_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _
time line [0 - 29]
for profiling, you can choose async-profiler which already including in bin path of java-debug-tool.
we will use a simple case to show the usage of java-debug-tool:
import java.util.Random;
import java.util.concurrent.TimeUnit;
public class Demo {
private void say(String word, boolean tag, int rdm) {
if (word == null) {
word = "test say";
}
int length = word.length();
if (tag) {
length += 1;
} else {
length -= 1;
}
word += "@" + length;
System.out.println(word);
if (rdm > 5) {
throw new IllegalStateException("test exception");
}
}
private static final String[] list = {"a", "ab", "abc", "abcd"};
public static void main(String[] args) {
Demo demo = new Demo();
Random random = new Random(47);
new Thread(new Runnable() {
@Override
public void run() {
for(;;) {
try {
demo.say(list[random.nextInt(4)], random.nextBoolean(), random.nextInt(10));
TimeUnit.MILLISECONDS.sleep(100);
} catch (Exception e) {
e.printStackTrace();
}
}
}
}, "demo-thread").start();
}
}the 'mt' command (aka method trace) is the main command of java-debug-tool, this command can offer many runtime info of target method:
- Action time
- caller thread
- method params
- line cost
- invoked line number
- line variables
- return val
- exception
- call stack
using 'list' command to show all of the commands, then use 'help' command to get the usage of the command;
list
h -cmd list
h -cmd mt
h -cmd monitor
...
127.0.0.1:11234>list
---------------------------------------------------------------------------------------------
Command ：list
Round ：2
ClientId ：10000
ClientType ：console:1
Version ：version:1
CommandCost ：4 (ms)
STW_Cost ：0 (ms)
Time: : Sun Feb 02 17:22:20 CST 2020
---------------------------------------------------------------------------------------------
fc
help
list
exit
alive
redefine
rollback
lock
set
info
trace
mt
ct
thread
monitor
btrace
---------------------------------------------------------------------------------------------
127.0.0.1:11234>h -cmd list
---------------------------------------------------------------------------------------------
Command ：h
Round ：3
ClientId ：10000
ClientType ：console:1
Version ：version:1
CommandCost ：7 (ms)
STW_Cost ：0 (ms)
Time: : Sun Feb 02 17:22:39 CST 2020
---------------------------------------------------------------------------------------------
Command : list | all
Function : list commands
Usage : list | all
Type : COMPUTE
---------------------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Thread Dynamic Statistic
--------------------------------------------------------------------------------
----- ----- ----- -----
tid name s cpu%
----- ----- ----- -----
11 test-test-R-worker TW 95%
20 Java-Debug-Tool-WebSocket-Server-Worker R 5%
Total Thread : 13, New : 0, Runnable : 7, Blocked : 0, Waiting : 4, Timed Waiting : 2, Terminated : 0
--- System Load ---
AvailableProcessors 8
SystemLoadAverage 3.18652343
ProcessCpuLoad 0.01164025
--------------------------------------------------------------------------------
q
127.0.0.1:11234>mt -c R -m call
---------------------------------------------------------------------------------------------
Command ：mt
Round ：6
ClientId ：10000
ClientType ：console:1
Version ：version:1
CommandCost ：411 (ms)
STW_Cost ：68 (ms)
Time: : Sun Feb 02 17:23:52 CST 2020
---------------------------------------------------------------------------------------------
[R.call] invoke by Thread:Thread[test-test-R-worker,5,main]
with params
[
[0] @class:java.lang.Integer -> 6,
[1] @class:java.lang.Integer -> 6,
[2] @class:C -> {"@class":"C","a":0},
[3] @unknown -> NULL,
[4] @unknown -> NULL,
[5] @unknown -> NULL,
[6] @unknown -> NULL,
[7] @class:java.util.ArrayList -> ["java.util.ArrayList",[{"@class":"R$MMM","data":"test"}]]
]
[0 ms] (73) [mmmList1 = ["java.util.ArrayList",[{"@class":"R$MMM","data":"test"}]]]
[0 ms] (74)
[0 ms] (75)
[0 ms] (79)
[0 ms] (83) [el = -1]
[0 ms] (84)
[0 ms] (89)
[0 ms] (93)
[0 ms] (97)
[0 ms] (99) [sa = 1]
[0 ms] (100)
[1 ms] (101) [ii = 0]
[0 ms] (102) [ij = 0]
[0 ms] (103) [jk = 1]
[0 ms] (104) [f = 1.0]
[0 ms] (105) [d = 0.123]
[0 ms] (106) [name = "hello6,6"]
[0 ms] (107) [list = ["java.util.ArrayList",[6,7]]]
[0 ms] (108)
[0 ms] (109)
[0 ms] (110)
[0 ms] (112)
[0 ms] (115)
[0 ms] (118)
[0 ms] (119)
throw exception:[java.lang.IllegalArgumentException: i + j <= 10:66] at line:119 with cost:3 ms
-R.call
-R$1.run at line:152
-java.lang.Thread.run at line:748
---------------------------------------------------------------------------------------------
- agent
the agent code, do attach work.
- core
the java-debug-tool's biz codes, including netty-handler, debug-client / debug-server, command handler, etc;
- test
the test module, test codes write here;
- script
the java-debug-tool's script dir;
- bin
the target bin dir;
cd script
./javadebug-pack.sh
enjoy !
//
// ========================================================================
// Copyright (c) 2018-2019 HuJian/Pandening soft collection.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the #{license} Public License #{version}
// EG:
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
// You should bear the consequences of using the software (named 'java-debug-tool')
// and any modify must be create an new pull request and attach an text to describe
// the change detail.
// ========================================================================
//
- Netty : Transport support.
- JLine : Console support.
- jna : java native access support.
- ASM : java bytecode weaver.
- arthas : java-debut-tool reference arthas.
- async-profiler : profiling support.
Thanks for the excellent work in these projects!
![@dependabot[bot]](https://avatars.githubusercontent.com/in/29110?s=64&v=4){kind=small}