Add code coverage

Author: Theosakamg

rcljava_utils/build.gradle

@@ -1,8 +1,11 @@
 plugins {
     id "org.ros2.rcljava" version "0.4.6"
+    id 'jacoco'
+    id 'com.github.kt3k.coveralls' version '2.8.1'
 }
 
 apply plugin: 'org.ros2.rcljava'
+apply plugin: 'jacoco'
 
 sourceCompatibility = 1.7
 targetCompatibility = 1.7
@@ -35,3 +38,14 @@ ament {
         }
     }
 }
+
+
+test { finalizedBy jacocoTestReport }
+
+jacocoTestReport {
+    reports {
+        xml.enabled = true // coveralls plugin depends on xml format report
+        html.enabled = true
+    }
+    finalizedBy 'coveralls'
+}

rcljava_utils/src/test/java/com/ros2/rcljava/tool/TestRos2Topics.java

@@ -0,0 +1,47 @@
+package com.ros2.rcljava.tool;
+
+import static org.junit.Assert.*;
+
+import java.util.ArrayList;
+
+import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.Before;
+import org.junit.BeforeClass;
+import org.junit.Ignore;
+import org.junit.Test;
+import org.ros2.rcljava.RCLJava;
+import org.ros2.rcljava.tool.Ros2Topics;
+
+public class TestRos2Topics {
+
+    @BeforeClass
+    public static void setUpBeforeClass() throws Exception {
+    }
+
+    @AfterClass
+    public static void tearDownAfterClass() throws Exception {
+    }
+
+    @Before
+    public void setUp() throws Exception {
+    }
+
+    @After
+    public void tearDown() throws Exception {
+    }
+
+    @Test
+    @Ignore
+    public final void testFullUsage() throws InterruptedException {
+        Ros2Topics.main(new String[]{});
+        assertEquals(true, true);
+    }
+
+    @Test
+    public final void testList() throws InterruptedException {
+        Ros2Topics.main(new String[]{"list"});
+        assertEquals(true, true);
+    }
+
+}

rcljava_utils/src/test/java/com/ros2/rcljava/tool/package-info.java

@@ -0,0 +1,4 @@
+/**
+ *
+ */
+package com.ros2.rcljava.tool;