fix: Sometimes failed to attach the debugee (#1272)

extension/src/terminal/GradleRunnerTerminal.ts

@@ -57,9 +57,8 @@ export class GradleRunnerTerminal implements vscode.Pseudoterminal {
                 reject(new Error("The task completed without the debugger being attached"));
             });
         });
-        const logError = (err: Error): void => logger.error("Unable to start Java debugging:", err.message);
-        Promise.race([waitOnTcp("localhost", javaDebugPort), closePromise])
-            .then(async () => {
+        Promise.race([waitOnTcp("localhost", javaDebugPort), closePromise]).then(
+            async () => {
                 const definition = this.task?.definition as GradleTaskDefinition;
                 const projectName = definition ? definition.project : undefined;
                 const debugConfig = {
@@ -77,11 +76,14 @@ export class GradleRunnerTerminal implements vscode.Pseudoterminal {
                 if (!startedDebugging) {
                     throw new Error("The debugger was not started");
                 }
-            }, logError)
-            .catch((err) => {
-                logError(err);
-                return this.close();
-            });
+            },
+            (err) => {
+                const errorMessage = "Unable to start Java debugging:" + err.message;
+                logger.error(errorMessage);
+                vscode.window.showErrorMessage(errorMessage);
+                this.close();
+            }
+        );
     }
 
     private async runBuild(): Promise<void> {

extension/src/util/index.ts

@@ -8,7 +8,8 @@ export const isTest = (): boolean => process.env.VSCODE_TEST?.toLowerCase() ===
 
 export const isDebuggingServer = (): boolean => process.env.VSCODE_DEBUG_SERVER?.toLowerCase() === "true";
 
-const maximumTimeout = 10000; // ms
+// some run application tasks require a lot of time to start. So we should set a loose timeout.
+const maximumTimeout = 60000; // ms
 const tcpTimeout = 300; // ms
 
 function tcpExists(host: string, port: number): Promise<boolean> {
@@ -32,10 +33,19 @@ function tcpExists(host: string, port: number): Promise<boolean> {
     });
 }
 
+function sleep(time: number) {
+    return new Promise((resolve) => setTimeout(resolve, time));
+}
+
 async function tryConnect(host: string, port: number, startTime: number): Promise<void> {
     const connected = await tcpExists(host, port);
     if (connected) {
-        return;
+        // workaround: experimental re-checking after waiting for 1s
+        await sleep(1000);
+        const connectedRetry = await tcpExists(host, port);
+        if (connectedRetry) {
+            return;
+        }
     }
     if (Date.now() - startTime >= maximumTimeout) {
         throw new Error("Unable to wait on tcp due to maxmium timeout reached");