Initial library commit

src/main/java/mcp/server/ToolRegistrationServlet.java

@@ -0,0 +1,87 @@
+package mcp.server;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import jakarta.servlet.http.HttpServlet;
+import jakarta.servlet.http.HttpServletRequest;
+import jakarta.servlet.http.HttpServletResponse;
+import mcp.registry.DynamicToolLoader;
+import mcp.registry.ToolRegistry;
+import mcp.tools.McpTool;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+import mcp.util.Err;
+import mcp.util.Ok;
+import mcp.util.Result;
+
+import java.io.IOException;
+import java.util.Map;
+
+/**
+ * A Servlet that provides an endpoint for dynamic registration of external tools.
+ * <p>
+ * Expects a POST request with a JSON body:
+ * <pre>
+ * {
+ *   "jarPath": "/path/to/tools.jar",
+ *   "className": "com.example.MyTool"
+ * }
+ * </pre>
+ */
+public class ToolRegistrationServlet extends HttpServlet {
+    private static final Logger logger = LoggerFactory.getLogger(ToolRegistrationServlet.class);
+
+    private final ToolRegistry toolRegistry;
+    private final ObjectMapper objectMapper = new ObjectMapper();
+
+    public ToolRegistrationServlet(ToolRegistry toolRegistry) {
+        this.toolRegistry = toolRegistry;
+    }
+
+    @Override
+    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws IOException {
+        logger.debug("Received tool registration request");
+        try {
+            Map<String, String> body = objectMapper.readValue(req.getInputStream(), Map.class);
+            String jarPath = body.get("jarPath");
+            String className = body.get("className");
+
+            if (jarPath == null || className == null) {
+                logger.warn("Missing jarPath or className in registration request");
+                resp.setStatus(HttpServletResponse.SC_BAD_REQUEST);
+                resp.getWriter().write("Missing jarPath or className");
+                return;
+            }
+
+            logger.info("Attempting to register tool: {} from {}", className, jarPath);
+            final Result<McpTool, Exception> result = registerTool(jarPath, className);
+            switch (result) {
+                case Ok<McpTool, Exception> ok -> {
+                    final McpTool tool = ok.value();
+                    logger.info("Tool registered successfully: {}", tool.name());
+                    resp.setStatus(HttpServletResponse.SC_OK);
+                    resp.getWriter().write("Tool registered successfully: " + tool.name());
+                }
+                case Err<McpTool, Exception> err -> {
+                    logger.error("Error registering tool: {}", err.throwable().getMessage());
+                    resp.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
+                    resp.getWriter().write("Error registering tool: " + err.throwable().getMessage());
+                }
+            }
+
+        } catch (Exception e) {
+            logger.error("Unexpected error during tool registration", e);
+            resp.setStatus(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
+            resp.getWriter().write("Error registering tool: " + e.getMessage());
+        }
+    }
+
+    public Result<McpTool, Exception> registerTool(final String jarPath, final String className) {
+        try {
+            McpTool tool = DynamicToolLoader.loadTool(jarPath, className);
+            toolRegistry.register(tool);
+            return new Ok<>(tool);
+        } catch (Exception e) {
+            return new Err<>(e);
+        }
+    }
+}