Apply Gemini review: close HC5 HttpClient on shutdown

Both ToolRegistry and McpStdioServer now implement Closeable with
close() calling httpClient.close(). McpBridgeMain uses try-with-
resources to ensure connection pools are released when stdin closes
(Claude Desktop terminates the MCP subprocess).

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: robertlazarski

modules/mcp-bridge/src/main/java/org/apache/axis2/mcp/bridge/McpBridgeMain.java

@@ -88,11 +88,13 @@ public static void main(String[] args) {
                     keystorePath, keystorePass.toCharArray(),
                     truststorePath, truststorePass.toCharArray());
 
-            ToolRegistry registry = new ToolRegistry(baseUrl, mapper, sslContext);
-            registry.load();
+            try (ToolRegistry registry = new ToolRegistry(baseUrl, mapper, sslContext)) {
+                registry.load();
 
-            McpStdioServer server = new McpStdioServer(baseUrl, registry, mapper, sslContext);
-            server.run();
+                try (McpStdioServer server = new McpStdioServer(baseUrl, registry, mapper, sslContext)) {
+                    server.run();
+                }
+            }
 
         } catch (Exception e) {
             System.err.println("[axis2-mcp-bridge] Fatal: " + e.getMessage());

modules/mcp-bridge/src/main/java/org/apache/axis2/mcp/bridge/McpStdioServer.java

@@ -57,7 +57,7 @@
  * <p>Notifications (messages without an {@code id} field) are silently consumed
  * with no response, as required by JSON-RPC 2.0.
  */
-public class McpStdioServer {
+public class McpStdioServer implements java.io.Closeable {
 
     private static final String PROTOCOL_VERSION = "2024-11-05";
     private static final String SERVER_NAME = "axis2-mcp-bridge";
@@ -281,4 +281,9 @@ private void writeLine(String json) {
         out.println(json);
         out.flush();
     }
+
+    @Override
+    public void close() throws IOException {
+        httpClient.close();
+    }
 }

modules/mcp-bridge/src/main/java/org/apache/axis2/mcp/bridge/ToolRegistry.java

@@ -47,7 +47,7 @@
  * It is fetched once at startup; restart the bridge to pick up newly deployed
  * services.
  */
-public class ToolRegistry {
+public class ToolRegistry implements java.io.Closeable {
 
     private final String baseUrl;
     private final ObjectMapper mapper;
@@ -140,4 +140,9 @@ public void load() throws IOException {
     public List<McpTool> getTools() { return tools; }
 
     public McpTool getTool(String name) { return toolMap.get(name); }
+
+    @Override
+    public void close() throws IOException {
+        httpClient.close();
+    }
 }