jdwp

Java Debug Wire Protocol

Install

$ npm i jdwp --save

Usage

launch the java project and connect to jvm

const { launcher } = require('jdwp')

const vm = await launcher.launch({
  mainClass: 'Test',
  vmArgs: [ '-Dfile.encoding=UTF-8', '-Xdebug', '-Xnoagent', '-Djava.compiler=NONE' ],
  classPaths: [ __dirname ],
});
vm.on('event', async ({ events }) => {
  console.log(events);
});
await vm.ready();
await vm.resume();

run the example demo

$ node example/index.js

Begin debug Test.java
-----------------------
1  public class Test {
2      public int plus(int a, int b) {
3      	int c = a + b;
4      	return c;
5      }
6
7      public static void main(String[] args) {
8      	Test test = new Test();
9      	int c = test.plus(1, 2);
10      	System.out.println(c);
11          System.out.println("Hello world");
12      }
13  }
14
-----------------------

suspend at breakpoint line:10
get local variable c = 3
set local variable c = 4
4
step => Test main() line:11 Test/Test.java
Hello world
step => Test main() line:12 Test/Test.java
step => java.lang.Thread exit() line:757 java/lang/Thread/Thread.java
step => java.lang.Thread exit() line:758 java/lang/Thread/Thread.java
step => java.lang.Thread exit() line:759 java/lang/Thread/Thread.java
step => java.lang.Thread exit() line:762 java/lang/Thread/Thread.java
step => java.lang.Thread exit() line:764 java/lang/Thread/Thread.java
step => java.lang.Thread exit() line:765 java/lang/Thread/Thread.java
step => java.lang.Thread exit() line:766 java/lang/Thread/Thread.java
step => java.lang.Thread exit() line:767 java/lang/Thread/Thread.java
step => java.lang.Thread exit() line:768 java/lang/Thread/Thread.java
step => java.lang.Thread exit() line:769 java/lang/Thread/Thread.java

Protocol

https://docs.oracle.com/javase/7/docs/platform/jpda/jdwp/jdwp-protocol.html

• VirtualMachine Command Set (1)
  • [x] Version (1)
  • [x] ClassesBySignature (2)
  • [x] AllClasses (3)
  • [x] AllThreads (4)
  • [x] TopLevelThreadGroups (5)
  • [x] Dispose (6)
  • [x] IDSizes (7)
  • [x] Suspend (8)
  • [x] Resume (9)
  • [x] Exit (10)
  • [x] CreateString (11)
  • [x] Capabilities (12)
  • [x] ClassPaths (13)
  • [ ] DisposeObjects (14)
  • [x] HoldEvents (15)
  • [x] ReleaseEvents (16)
  • [x] CapabilitiesNew (17)
  • [x] RedefineClasses (18)
  • [x] SetDefaultStratum (19)
  • [x] AllClassesWithGeneric (20)
  • [x] InstanceCounts (21)
• ReferenceType Command Set (2)
  • [x] Signature (1)
  • [x] ClassLoader (2)
  • [x] Modifiers (3)
  • [x] Fields (4)
  • [x] Methods (5)
  • [x] GetValues (6)
  • [x] SourceFile (7)
  • [x] NestedTypes (8)
  • [x] Status (9)
  • [x] Interfaces (10)
  • [x] ClassObject (11)
  • [x] SourceDebugExtension (12)
  • [x] SignatureWithGeneric (13)
  • [x] FieldsWithGeneric (14)
  • [x] MethodsWithGeneric (15)
  • [x] Instances (16)
  • [x] ClassFileVersion (17)
  • [x] ConstantPool (18)
• ClassType Command Set (3)
  • [x] Superclass (1)
  • [x] SetValues (2)
  • [x] InvokeMethod (3)
  • [x] NewInstance (4)
• ArrayType Command Set (4)
  • [x] NewInstance (1)
• InterfaceType Command Set (5)
• Method Command Set (6)
  • [x] LineTable (1)
  • [x] VariableTable (2)
  • [x] Bytecodes (3)
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• Field Command Set (8)
• ObjectReference Command Set (9)
  • [x] ReferenceType (1)
  • [x] GetValues (2)
  • [x] SetValues (3)
  • [x] MonitorInfo (5)
  • [x] InvokeMethod (6)
  • [x] DisableCollection (7)
  • [x] EnableCollection (8)
  • [x] IsCollected (9)
  • [x] ReferringObjects (10)
• StringReference Command Set (10)
  • [x] Value (1)
• ThreadReference Command Set (11)
  • [x] Name (1)
  • [x] Suspend (2)
  • [x] Resume (3)
  • [x] Status (4)
  • [x] ThreadGroup (5)
  • [x] Frames (6)
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  • [ ] OwnedMonitorsStackDepthInfo (13)
  • [x] ForceEarlyReturn (14)
• ThreadGroupReference Command Set (12)
  • [x] Name (1)
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  • [x] Children (3)
• ArrayReference Command Set (13)
  • [x] Length (1)
  • [x] GetValues (2)
  • [x] SetValues (3)
• ClassLoaderReference Command Set (14)
  • [x] VisibleClasses (1)
• EventRequest Command Set (15)
  • [x] Set (1)
  • [x] Clear (2)
  • [x] ClearAllBreakpoints (3)
• StackFrame Command Set (16)
  • [x] GetValues (1)
  • [x] SetValues (2)
  • [x] ThisObject (3)
  • [x] PopFrames (4)
• ClassObjectReference Command Set (17)
  • [x] ReflectedType (1)
• Event Command Set (64)
  • [x] Composite (100)