Add SocketUtils

spring-cloud-function-context/src/main/java/org/springframework/cloud/function/utils/SocketUtils.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright 2022-2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.cloud.function.utils;
+
+import java.net.ServerSocket;
+
+public final class SocketUtils {
+
+	private SocketUtils() {
+	}
+
+	public static int findAvailableTcpPort() {
+		try {
+			ServerSocket s = new ServerSocket(0);
+			int port = s.getLocalPort();
+			s.close();
+			return port;
+		}
+		catch (Exception e) {
+			// ignore
+		}
+		return 0;
+	}
+}