1 files changed, 113 insertions, 0 deletions
diff --git a/utils/src/main/java/org/onap/policy/common/utils/network/NetworkUtil.java b/utils/src/main/java/org/onap/policy/common/utils/network/NetworkUtil.java
new file mode 100644
index 00000000..c9afa19e
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+++ b/utils/src/main/java/org/onap/policy/common/utils/network/NetworkUtil.java
@@ -0,0 +1,113 @@
+/*-
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2017-2018 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * 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
+ *
+ *      http://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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.common.utils.network;
+
+import java.io.IOException;
+import java.net.ConnectException;
+import java.net.InetAddress;
+import java.net.Socket;
+import java.net.UnknownHostException;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Network Utilities
+ */
+public class NetworkUtil {
+
+    public static final Logger logger = LoggerFactory.getLogger(NetworkUtil.class.getName());
+
+    /**
+     * IPv4 Wildcard IP address
+     */
+    public static final String IPv4_WILDCARD_ADDRESS = "0.0.0.0";
+
+    private NetworkUtil() {
+        // Empty constructor
+    }
+
+    /**
+     * try to connect to $host:$port $retries times while we are getting connection failures.
+     *
+     * @param host host
+     * @param port port
+     * @param retries number of attempts
+     * @return true is port is open, false otherwise
+     * @throws InterruptedException if execution has been interrupted
+     */
+    public static boolean isTcpPortOpen(String host, int port, int retries, long interval)
+            throws InterruptedException, IOException {
+        int retry = 0;
+        while (retry < retries) {
+            try (Socket s = new Socket(host, port)) {
+                logger.debug("{}:{} connected - retries={} interval={}", host, port, retries, interval);
+                return true;
+            } catch (final ConnectException e) {
+                retry++;
+                logger.trace("{}:{} connected - retries={} interval={}", host, port, retries, interval, e);
+                Thread.sleep(interval);
+            }
+        }
+
+        logger.warn("{}:{} closed = retries={} interval={}", host, port, retries, interval);
+        return false;
+    }
+
+    /**
+     * gets host name
+     *
+     * @return host name
+     */
+    public static String getHostname() {
+
+        String hostname = System.getenv("HOSTNAME");
+        if (hostname != null && !hostname.isEmpty()) {
+            return hostname;
+        }
+
+        try {
+            return InetAddress.getLocalHost().getHostName();
+        } catch (UnknownHostException e) {
+            logger.warn("cannot resolve local hostname", e);
+            /* continue */
+        }
+
+        return "localhost";
+    }
+
+    /**
+     * gets host's IP
+     *
+     * @return host IP
+     */
+    public static String getHostIp() {
+
+        try {
+            return InetAddress.getLocalHost().getHostAddress();
+        } catch (UnknownHostException e) {
+            logger.warn("cannot resolve local hostname", e);
+            /* continue */
+        }
+
+        return "127.0.0.1";
+    }
+}