Use FQDN if possible.

pom.xml

@@ -76,6 +76,24 @@
       <version>14.0</version>
       <scope>test</scope>
     </dependency>
+    <dependency>
+        <groupId>org.powermock</groupId>
+        <artifactId>powermock-module-junit4</artifactId>
+        <version>1.5.4</version>
+        <scope>test</scope>
+    </dependency>
+    <dependency>
+        <groupId>org.powermock</groupId>
+        <artifactId>powermock-api-mockito</artifactId>
+        <version>1.5.4</version>
+        <scope>test</scope>
+    </dependency>
+    <dependency>
+        <groupId>org.mockito</groupId>
+        <artifactId>mockito-core</artifactId>
+        <version>1.8.5</version>
+        <scope>test</scope>
+    </dependency>
   </dependencies>
 
   <build>

src/main/java/me/moocar/logbackgelf/util/InternetUtils.java

@@ -15,6 +15,8 @@
 import java.net.UnknownHostException;
 
 public class InternetUtils {
+    private static final String REGEX_IP_ADDRESS = "\\d+(\\.\\d+){3}";
+
     private InternetUtils() {
     }
 
@@ -23,6 +25,10 @@ private InternetUtils() {
      */
     public static String getLocalHostName() throws SocketException, UnknownHostException {
         try {
+            final String canonicalHostName = InetAddress.getLocalHost().getCanonicalHostName();
+            if (canonicalHostName.contains(".") && !canonicalHostName.matches(REGEX_IP_ADDRESS)) {
+                return canonicalHostName;
+            }
             return InetAddress.getLocalHost().getHostName();
         } catch (UnknownHostException e) {
             NetworkInterface networkInterface = NetworkInterface.getNetworkInterfaces().nextElement();

src/test/java/me/moocar/logbackgelf/util/InternetUtilsTest.java

@@ -0,0 +1,59 @@
+package me.moocar.logbackgelf.util;
+
+import java.net.InetAddress;
+import java.net.SocketException;
+import java.net.UnknownHostException;
+
+import org.junit.Assert;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.Mock;
+import org.powermock.api.mockito.PowerMockito;
+import org.powermock.core.classloader.annotations.PrepareForTest;
+import org.powermock.modules.junit4.PowerMockRunner;
+
+@RunWith(PowerMockRunner.class)
+@PrepareForTest(InternetUtils.class)
+public class InternetUtilsTest {
+	private static final String RESULT_HOSTNAME = "hostname";
+	private static final String RESULT_FQDN = "hostname.with.do-main";
+	private static final String RESULT_IP = "1.2.3.4";
+
+	@Mock
+	private InetAddress myAddress;
+
+	@Before
+	public void setUp() throws UnknownHostException {
+		PowerMockito.mockStatic(InetAddress.class);
+		PowerMockito.when(InetAddress.getLocalHost()).thenReturn(myAddress);
+	}
+
+	@Test
+	public void testHostFQDN() throws UnknownHostException, SocketException {
+		PowerMockito.when(myAddress.getHostName()).thenReturn(RESULT_HOSTNAME);
+		PowerMockito.when(myAddress.getCanonicalHostName()).thenReturn(RESULT_FQDN);
+		Assert.assertEquals(RESULT_FQDN, InternetUtils.getLocalHostName());
+	}
+
+	@Test
+	public void testHostIP() throws UnknownHostException, SocketException {
+		PowerMockito.when(myAddress.getHostName()).thenReturn(RESULT_HOSTNAME);
+		PowerMockito.when(myAddress.getCanonicalHostName()).thenReturn(RESULT_IP);
+		Assert.assertEquals(RESULT_HOSTNAME, InternetUtils.getLocalHostName());
+	}
+
+	@Test
+	public void testFQDNIP() throws UnknownHostException, SocketException {
+		PowerMockito.when(myAddress.getHostName()).thenReturn(RESULT_FQDN);
+		PowerMockito.when(myAddress.getCanonicalHostName()).thenReturn(RESULT_IP);
+		Assert.assertEquals(RESULT_FQDN, InternetUtils.getLocalHostName());
+	}
+
+	@Test
+	public void testIPFQDN() throws UnknownHostException, SocketException {
+		PowerMockito.when(myAddress.getHostName()).thenReturn(RESULT_IP);
+		PowerMockito.when(myAddress.getCanonicalHostName()).thenReturn(RESULT_FQDN);
+		Assert.assertEquals(RESULT_FQDN, InternetUtils.getLocalHostName());
+	}
+}