feat: java home set

Author: wenytang-ms

bundled/scripts/noConfigScripts/README.md

@@ -62,11 +62,15 @@ debugjava -jar myapp.jar --spring.profiles.active=dev
 ## How It Works Internally
 
 1. When you run `debugjava`, the wrapper script temporarily sets `JAVA_TOOL_OPTIONS=-agentlib:jdwp=transport=dt_socket,server=y,suspend=y,address=0`
-2. The wrapper launches the Java process with JDWP enabled
-3. JVM starts and outputs: "Listening for transport dt_socket at address: 12345"
-4. The wrapper captures the JDWP port from this output
-5. The port is written to a communication file
-6. VS Code's file watcher detects the file and automatically starts an attach debug session
+2. The wrapper determines which Java executable to use (priority order):
+   - First: `JAVA_HOME/bin/java` if JAVA_HOME environment variable is set (user's explicit choice)
+   - Second: `VSCODE_JAVA_EXEC` environment variable (Java path from VS Code's Java Language Server)
+   - Third: `java` command from system PATH
+3. The wrapper launches the Java process with JDWP enabled
+4. JVM starts and outputs: "Listening for transport dt_socket at address: 12345"
+5. The wrapper captures the JDWP port from this output
+6. The port is written to a communication file
+7. VS Code's file watcher detects the file and automatically starts an attach debug session
 
 ## Troubleshooting
 

bundled/scripts/noConfigScripts/jdwp-wrapper.js

@@ -23,9 +23,8 @@ const isDebugEnabled = javaToolOptions.includes('jdwp') && endpointFile;
 
 // Helper function to find java command
 function getJavaCommand() {
+    // Priority 1: Try JAVA_HOME environment variable first (user's explicit choice)
     const javaHome = process.env.JAVA_HOME;
-    
-    // Try JAVA_HOME first
     if (javaHome) {
         const javaPath = path.join(javaHome, 'bin', 'java');
         const javaPathExe = process.platform === 'win32' ? `${javaPath}.exe` : javaPath;
@@ -38,10 +37,16 @@ function getJavaCommand() {
             return javaPath;
         }
 
-        console.warn(`[Java Debug] JAVA_HOME is set to '${javaHome}', but java command not found there. Falling back to PATH.`);
+        console.warn(`[Java Debug] JAVA_HOME is set to '${javaHome}', but java command not found there. Falling back to VS Code's Java.`);
+    }
+    
+    // Priority 2: Use VSCODE_JAVA_EXEC if provided by VS Code (from Java Language Server)
+    const vscodeJavaExec = process.env.VSCODE_JAVA_EXEC;
+    if (vscodeJavaExec && fs.existsSync(vscodeJavaExec)) {
+        return vscodeJavaExec;
     }
 
-    // Fall back to 'java' in PATH
+    // Priority 3: Fall back to 'java' in PATH
     return 'java';
 }
 

src/noConfigDebugInit.ts

@@ -7,6 +7,7 @@ import * as crypto from 'crypto';
 import * as vscode from 'vscode';
 
 import { sendInfo, sendError } from "vscode-extension-telemetry-wrapper";
+import { getJavaHome } from "./utility";
 
 /**
  * Registers the configuration-less debugging setup for the extension.
@@ -76,6 +77,19 @@ export async function registerNoConfigDebug(
     // only in the debugjava wrapper scripts (debugjava.ps1, debugjava.bat, debugjava)
     collection.replace('VSCODE_JDWP_ADAPTER_ENDPOINTS', tempFilePath);
 
+    // Try to get Java executable from Java Language Server
+    // This ensures we use the same Java version as the project is compiled with
+    try {
+        const javaHome = await getJavaHome();
+        if (javaHome) {
+            const javaExec = path.join(javaHome, 'bin', 'java');
+            collection.replace('VSCODE_JAVA_EXEC', javaExec);
+        }
+    } catch (error) {
+        // If we can't get Java from Language Server, that's okay
+        // The wrapper script will fall back to JAVA_HOME or PATH
+    }
+
     const noConfigScriptsDir = path.join(extPath, 'bundled', 'scripts', 'noConfigScripts');
     const pathSeparator = process.platform === 'win32' ? ';' : ':';