Add extensibility points to DebugAdapter and ProtocolServer (#509)

Co-authored-by: Vladimir Makayev <vmakaev@fb.com>
Co-authored-by: Jinbo Wang <jinbwan@microsoft.com>

Author: 3 people

com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/DebugAdapter.java

@@ -102,7 +102,7 @@ public CompletableFuture<Messages.Response> dispatchRequest(Messages.Request req
         }
     }
 
-    private void initialize() {
+    protected void initialize() {
         // Register request handlers.
         // When there are multiple handlers registered for the same request, follow the rule "first register, first execute".
         registerHandler(new InitializeRequestHandler());
@@ -141,15 +141,15 @@ private void initialize() {
         registerHandlerForNoDebug(new ProcessIdHandler());
     }
 
-    private void registerHandlerForDebug(IDebugRequestHandler handler) {
+    protected void registerHandlerForDebug(IDebugRequestHandler handler) {
         registerHandler(requestHandlersForDebug, handler);
     }
 
-    private void registerHandlerForNoDebug(IDebugRequestHandler handler) {
+    protected void registerHandlerForNoDebug(IDebugRequestHandler handler) {
         registerHandler(requestHandlersForNoDebug, handler);
     }
 
-    private void registerHandler(IDebugRequestHandler handler) {
+    protected void registerHandler(IDebugRequestHandler handler) {
         registerHandler(requestHandlersForDebug, handler);
         registerHandler(requestHandlersForNoDebug, handler);
     }
@@ -165,4 +165,5 @@ private void registerHandler(Map<Command, List<IDebugRequestHandler>> requestHan
             handlerList.add(handler);
         }
     }
+
 }

com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/IDebugAdapterFactory.java

@@ -0,0 +1,19 @@
+/*******************************************************************************
+ * Copyright (c) 2023 Microsoft Corporation and others.
+ * All rights reserved. This program and the accompanying materials
+ * are made available under the terms of the Eclipse Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/epl-v10.html
+ *
+ * Contributors:
+ *     Microsoft Corporation - initial API and implementation
+*******************************************************************************/
+
+package com.microsoft.java.debug.core.adapter;
+
+import com.microsoft.java.debug.core.protocol.IProtocolServer;
+
+@FunctionalInterface
+public interface IDebugAdapterFactory {
+    public IDebugAdapter create(IProtocolServer server);
+}

com.microsoft.java.debug.core/src/main/java/com/microsoft/java/debug/core/adapter/ProtocolServer.java

@@ -52,6 +52,20 @@ public ProtocolServer(InputStream input, OutputStream output, IProviderContext c
         debugAdapter = new DebugAdapter(this, context);
     }
 
+    /**
+     * Constructs a protocol server instance based on the given input stream and output stream.
+     * @param input
+     *              the input stream
+     * @param output
+     *              the output stream
+     * @param debugAdapterFactory
+     *              factory to create debug adapter that implements DAP communication
+     */
+    public ProtocolServer(InputStream input, OutputStream output, IDebugAdapterFactory debugAdapterFactory) {
+        super(input, output);
+        debugAdapter = debugAdapterFactory.create(this);
+    }
+
     /**
      * A while-loop to parse input data and send output data constantly.
      */