Merge pull request #374 from scijava/named-objects

Add named object index and improve ObjectService

Author: ctrueden

src/main/java/org/scijava/object/DefaultObjectService.java

@@ -32,14 +32,10 @@
 
 package org.scijava.object;
 
-import java.util.List;
-
 import org.scijava.event.EventHandler;
 import org.scijava.event.EventService;
 import org.scijava.object.event.ObjectCreatedEvent;
 import org.scijava.object.event.ObjectDeletedEvent;
-import org.scijava.object.event.ObjectsAddedEvent;
-import org.scijava.object.event.ObjectsRemovedEvent;
 import org.scijava.plugin.Parameter;
 import org.scijava.plugin.Plugin;
 import org.scijava.service.AbstractService;
@@ -68,7 +64,7 @@ public final class DefaultObjectService extends AbstractService implements
 	private EventService eventService;
 
 	/** Index of registered objects. */
-	private ObjectIndex<Object> objectIndex;
+	private NamedObjectIndex<Object> objectIndex;
 
 	// -- ObjectService methods --
 
@@ -78,35 +74,15 @@ public EventService eventService() {
 	}
 
 	@Override
-	public ObjectIndex<Object> getIndex() {
+	public NamedObjectIndex<Object> getIndex() {
 		return objectIndex;
 	}
 
-	@Override
-	public <T> List<T> getObjects(final Class<T> type) {
-		final List<Object> list = objectIndex.get(type);
-		@SuppressWarnings("unchecked")
-		final List<T> result = (List<T>) list;
-		return result;
-	}
-
-	@Override
-	public void addObject(final Object obj) {
-		objectIndex.add(obj);
-		eventService.publish(new ObjectsAddedEvent(obj));
-	}
-
-	@Override
-	public void removeObject(final Object obj) {
-		objectIndex.remove(obj);
-		eventService.publish(new ObjectsRemovedEvent(obj));
-	}
-
 	// -- Service methods --
 
 	@Override
 	public void initialize() {
-		objectIndex = new ObjectIndex<>(Object.class);
+		objectIndex = new NamedObjectIndex<>(Object.class);
 	}
 
 	// -- Event handlers --
@@ -120,5 +96,4 @@ protected void onEvent(final ObjectCreatedEvent event) {
 	protected void onEvent(final ObjectDeletedEvent event) {
 		removeObject(event.getObject());
 	}
-
 }

src/main/java/org/scijava/object/NamedObjectIndex.java

@@ -0,0 +1,34 @@
+package org.scijava.object;
+
+import java.util.WeakHashMap;
+
+/**
+ * An {@link ObjectIndex} where each object can have an associated name.
+ *
+ * @author Jan Eglinger
+ */
+public class NamedObjectIndex<E> extends ObjectIndex<E> {
+	
+	private WeakHashMap<Object, String> nameMap;
+
+	public NamedObjectIndex(final Class<E> baseClass) {
+		super(baseClass);
+		nameMap = new WeakHashMap<>();
+	}
+
+	public boolean add(E object, String name) {
+		if (name != null)
+			nameMap.put(object, name);
+		return add(object);
+	}
+
+	public boolean add(E object, Class<?> type, String name, boolean batch) {
+		if (name != null)
+			nameMap.put(object, name);
+		return add(object, type, batch);
+	}
+
+	public String getName(E object) {
+		return nameMap.get(object);
+	}
+}

src/main/java/org/scijava/object/ObjectService.java

@@ -34,7 +34,10 @@
 
 import java.util.List;
 
+import org.scijava.Named;
 import org.scijava.event.EventService;
+import org.scijava.object.event.ObjectsAddedEvent;
+import org.scijava.object.event.ObjectsRemovedEvent;
 import org.scijava.service.SciJavaService;
 
 /**
@@ -49,16 +52,54 @@ default EventService eventService() {
 	}
 
 	/** Gets the index of available objects. */
-	ObjectIndex<Object> getIndex();
+	NamedObjectIndex<Object> getIndex();
 
 	/** Gets a list of all registered objects compatible with the given type. */
-	<T> List<T> getObjects(Class<T> type);
+	default <T> List<T> getObjects(final Class<T> type) {
+		final List<Object> list = getIndex().get(type);
+		@SuppressWarnings("unchecked")
+		final List<T> result = (List<T>) list;
+		return result;
+	}
+
+	/**
+	 * Gets the name belonging to a given object.
+	 * <p>
+	 * If no explicit name was provided at registration time, the name will be
+	 * derived from {@link Named#getName()} if the object implements
+	 * {@link Named}, or from the {@link Object#toString()} otherwise. It is
+	 * guaranteed that this method will not return {@code null}.
+	 * </p>
+	 **/
+	default String getName(final Object obj) {
+		if (obj == null) throw new NullPointerException();
+		final String name = getIndex().getName(obj);
+		if (name != null) return name;
+		if (obj instanceof Named) {
+			final String n = ((Named) obj).getName();
+			if (n != null) return n;
+		}
+		final String s = obj.toString();
+		if (s != null) return s;
+		return obj.getClass().getName() + "@" + Integer.toHexString(obj.hashCode());
+	}
 
 	/** Registers an object with the object service. */
-	void addObject(Object obj);
+	default void addObject(Object obj) {
+		addObject(obj, null);
+	}
+
+	/** Registers a named object with the object service. */
+	default void addObject(final Object obj, final String name) {
+		getIndex().add(obj, name);
+		eventService().publish(new ObjectsAddedEvent(obj));
+	}
 
 	/** Deregisters an object with the object service. */
-	void removeObject(Object obj);
+	default void removeObject(final Object obj) {
+		getIndex().remove(obj);
+		eventService().publish(new ObjectsRemovedEvent(obj));
+	}
 
 	// -- Deprecated methods --
 

src/main/java/org/scijava/widget/DefaultWidgetModel.java

@@ -47,6 +47,7 @@
 import org.scijava.module.Module;
 import org.scijava.module.ModuleItem;
 import org.scijava.module.ModuleService;
+import org.scijava.object.ObjectService;
 import org.scijava.plugin.Parameter;
 import org.scijava.thread.ThreadService;
 import org.scijava.util.NumberUtils;
@@ -74,6 +75,9 @@ public class DefaultWidgetModel extends AbstractContextual implements WidgetMode
 	@Parameter
 	private ModuleService moduleService;
 
+	@Parameter
+	private ObjectService objectService;
+
 	@Parameter(required = false)
 	private LogService log;
 
@@ -227,7 +231,7 @@ public String[] getChoices() {
 		final List<?> choicesList = item.getChoices();
 		final String[] choices = new String[choicesList.size()];
 		for (int i = 0; i < choices.length; i++) {
-			choices[i] = choicesList.get(i).toString();
+			choices[i] = objectService.getName(choicesList.get(i));
 		}
 		return choices;
 	}

src/test/java/org/scijava/object/NamedObjectIndexTest.java

@@ -0,0 +1,43 @@
+package org.scijava.object;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+import org.junit.Test;
+
+public class NamedObjectIndexTest {
+
+	@Test
+	public void testNamedObjects() {
+		NamedObjectIndex<String> index = new NamedObjectIndex<>(String.class);
+		String obj1 = "obj1";
+		String name1 = "name1";
+		String obj2 = "obj1";
+		String name2 = "name1";
+		assertTrue(index.add(obj1, name1));
+		assertTrue(index.add(obj2, String.class, name2, false));
+		assertTrue(index.contains(obj1));
+		assertTrue(index.contains(obj2));
+		assertEquals(name1, index.getName(obj1));
+		assertEquals(name2, index.getName(obj2));
+		assertTrue(index.remove(obj1));
+		assertTrue(index.remove(obj2));
+		assertFalse(index.contains(obj1));
+		assertFalse(index.contains(obj2));
+	}
+
+	@Test
+	public void testNullNames() {
+		NamedObjectIndex<String> index = new NamedObjectIndex<>(String.class);
+		String obj1 = "object1";
+		String name1 = null;
+		String obj2 = "object2";
+		String name2 = "";
+		assertTrue(index.add(obj1, name1));
+		assertTrue(index.add(obj2, name2));
+		assertEquals(name1, index.getName(obj1));
+		assertEquals(name2, index.getName(obj2));
+	}
+}

src/test/java/org/scijava/object/ObjectServiceTest.java

@@ -0,0 +1,75 @@
+package org.scijava.object;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.scijava.Context;
+import org.scijava.plugin.PluginInfo;
+import org.scijava.plugin.SciJavaPlugin;
+
+public class ObjectServiceTest {
+
+	private Context context;
+	private ObjectService objectService;
+
+	@Before
+	public void setUp() {
+		context = new Context(ObjectService.class);
+		objectService = context.getService(ObjectService.class);
+	}
+
+	@After
+	public void tearDown() {
+		context.dispose();
+	}
+
+	@Test
+	public void testAddRemoveObjects() {
+		Object obj1 = new Object();
+		String name1 = "Object 1";
+		Object obj2 = "";
+		Object obj3 = new Double(0.3);
+		PluginInfo<SciJavaPlugin> obj4 = PluginInfo.create(TestPlugin.class, SciJavaPlugin.class);
+		obj4.setName("TestPlugin name");
+
+		objectService.addObject(obj1, name1);
+		assertEquals("Name of object 1", name1, objectService.getName(obj1));
+		objectService.addObject(obj2);
+		assertEquals("Name of object 2", obj2.toString(), objectService.getName(obj2));
+		objectService.addObject(obj3, null);
+		assertEquals("Name of object 3", obj3.toString(), objectService.getName(obj3));
+		objectService.addObject(obj4);
+		assertNotNull(objectService.getName(obj4));
+		assertEquals("Name of object 4", obj4.getName(), objectService.getName(obj4));
+
+		assertTrue("Object 1 registered", objectService.getObjects(Object.class).contains(obj1));
+		assertTrue("Object 2 registered", objectService.getObjects(Object.class).contains(obj2));
+		assertTrue("Object 3 registered", objectService.getObjects(Object.class).contains(obj3));
+		assertTrue("Object 4 registered", objectService.getObjects(Object.class).contains(obj4));
+
+		objectService.removeObject(obj1);
+		objectService.removeObject(obj2);
+		objectService.removeObject(obj3);
+		objectService.removeObject(obj4);
+
+		assertFalse("Object 1 removed", objectService.getObjects(Object.class).contains(obj1));
+		assertFalse("Object 2 removed", objectService.getObjects(Object.class).contains(obj2));
+		assertFalse("Object 3 removed", objectService.getObjects(Object.class).contains(obj3));
+		assertFalse("Object 4 removed", objectService.getObjects(Object.class).contains(obj4));
+	}
+
+	@Test
+	public void testNamedObjectIndex() {
+		ObjectIndex<Object> index = objectService.getIndex();
+		assertTrue(index instanceof NamedObjectIndex);
+	}
+
+	private class TestPlugin implements SciJavaPlugin {
+
+	}
+}