Adding tests for ParameterLoaderNode.

rosjava_helpers/build.gradle

-apply plugin: 'java'
-
 dependencies {
     compile project(':rosjava')
     compile 'org.yaml:snakeyaml:[1.17, 1.18)'
+    testCompile 'junit:junit:4.8.2'
+    testCompile project(':rosjava').sourceSets.test.output
 }

rosjava_helpers/src/test/java/org/ros/helpers/ParameterLoaderNodeTest.java

+/*
+ * Copyright (C) 2018 Ekumen, Inc.
+ *
+ * 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.
+ */
+package org.ros.helpers;
+
+
+import org.apache.commons.logging.Log;
+import org.junit.Before;
+import org.junit.Test;
+import org.ros.RosTest;
+import org.ros.exception.ParameterNotFoundException;
+import org.ros.namespace.GraphName;
+import org.ros.node.AbstractNodeMain;
+import org.ros.node.ConnectedNode;
+import org.ros.node.DefaultNodeListener;
+import org.ros.node.Node;
+import org.ros.node.NodeListener;
+import org.ros.node.parameter.ParameterTree;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.concurrent.CountDownLatch;
+import java.util.concurrent.TimeUnit;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+
+/**
+ * @author jubeira@ekumenlabs.com (Juan I. Ubeira)
+ */
+public class ParameterLoaderNodeTest extends RosTest {
+
+    private ParameterTree parameters;
+    private Log log;
+
+    @Before
+    public void setup() throws InterruptedException {
+        final CountDownLatch latch = new CountDownLatch(1);
+        nodeMainExecutor.execute(new AbstractNodeMain() {
+            @Override
+            public GraphName getDefaultNodeName() {
+                return GraphName.of("node_name");
+            }
+
+            @Override
+            public void onStart(ConnectedNode connectedNode) {
+                parameters = connectedNode.getParameterTree();
+                log = connectedNode.getLog();
+                latch.countDown();
+            }
+        }, nodeConfiguration);
+        assertTrue(latch.await(1, TimeUnit.SECONDS));
+    }
+
+    @Test
+    public void testParameterLoad() throws InterruptedException {
+        final String namespace = "foo";
+        List<ParameterLoaderNode.Resource> resourceList = new ArrayList<ParameterLoaderNode.Resource>() {{
+           add(new ParameterLoaderNode.Resource(getClass().getResourceAsStream("/parameters.yaml"), ""));
+           add(new ParameterLoaderNode.Resource(getClass().getResourceAsStream("/parameters.yaml"), namespace));
+        }};
+        ParameterLoaderNode parameterLoaderNode = new ParameterLoaderNode(resourceList);
+
+        final CountDownLatch parameterNodeLatch = new CountDownLatch(1);
+        nodeMainExecutor.execute(parameterLoaderNode, nodeConfiguration, new ArrayList<NodeListener>() {{
+            add(new DefaultNodeListener() {
+                @Override
+                public void onShutdown(Node node) {
+                    parameterNodeLatch.countDown();
+                }
+            });
+        }});
+
+        assertTrue(parameterNodeLatch.await(1, TimeUnit.SECONDS));
+
+        try {
+            // Without namespace.
+            assertEquals("bar", parameters.getString("/string_param"));
+            assertEquals(1823, parameters.getInteger("/int_param"));
+            assertEquals(1.74, parameters.getDouble("/double_param"), 0.001);
+            assertEquals(false, parameters.getBoolean("/boolean_param"));
+            List<?> list = parameters.getList("/list_param");
+            assertEquals("Hello", list.get(0));
+            assertEquals(1, list.get(1));
+            assertEquals(2.3, list.get(2));
+            assertEquals(true, list.get(3));
+
+            // With namespace.
+            assertEquals("bar", parameters.getString(namespace + "/string_param"));
+            assertEquals(1823, parameters.getInteger(namespace + "/int_param"));
+            assertEquals(1.74, parameters.getDouble(namespace + "/double_param"), 0.001);
+            assertEquals(false, parameters.getBoolean(namespace + "/boolean_param"));
+            list = parameters.getList(namespace + "/list_param");
+            assertEquals("Hello", list.get(0));
+            assertEquals(1, list.get(1));
+            assertEquals(2.3, list.get(2));
+            assertEquals(true, list.get(3));
+        } catch (ParameterNotFoundException e) {
+            log.error("Error: " + e.getMessage());
+            fail();
+        }
+    }
+
+    @Test
+    public void testEmptyYaml() throws InterruptedException {
+        List<ParameterLoaderNode.Resource> resourceList = new ArrayList<ParameterLoaderNode.Resource>() {{
+            add(new ParameterLoaderNode.Resource(getClass().getResourceAsStream("/empty.yaml"), ""));
+        }};
+        ParameterLoaderNode parameterLoaderNode = new ParameterLoaderNode(resourceList);
+
+        final CountDownLatch parameterNodeLatch = new CountDownLatch(1);
+        nodeMainExecutor.execute(parameterLoaderNode, nodeConfiguration, new ArrayList<NodeListener>() {{
+            add(new DefaultNodeListener() {
+                @Override
+                public void onShutdown(Node node) {
+                    parameterNodeLatch.countDown();
+                }
+            });
+        }});
+
+        // No exceptions shall be thrown on node execution, and it should shut down properly.
+        assertTrue(parameterNodeLatch.await(1, TimeUnit.SECONDS));
+    }
+}

rosjava_helpers/src/test/resources/parameters.yaml

+  string_param: "bar"
+  int_param: 1823
+  double_param: 1.74
+  boolean_param: false
+  list_param:
+    - "Hello"
+    - 1
+    - 2.3
+    - true
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