AppService: move default method impls to iface

Author: ctrueden

src/main/java/org/scijava/app/AppService.java

@@ -31,6 +31,7 @@
 
 package org.scijava.app;
 
+import java.util.List;
 import java.util.Map;
 
 import org.scijava.plugin.SingletonService;
@@ -44,7 +45,11 @@
 public interface AppService extends SingletonService<App>, SciJavaService {
 
 	/** Gets the foremost application (the one with the highest priority). */
-	App getApp();
+	default App getApp() {
+		final List<App> appList = getInstances();
+		if (appList == null || appList.isEmpty()) return null;
+		return appList.get(0);
+	}
 
 	/** Gets an application by name. */
 	App getApp(final String name);
@@ -56,4 +61,10 @@ public interface AppService extends SingletonService<App>, SciJavaService {
 	 */
 	Map<String, App> getApps();
 
+	// -- SingletonService methods --
+
+	@Override
+	default Class<App> getPluginType() {
+		return App.class;
+	}
 }

src/main/java/org/scijava/app/DefaultAppService.java

@@ -33,7 +33,6 @@
 
 import java.util.Collections;
 import java.util.HashMap;
-import java.util.List;
 import java.util.Map;
 
 import org.scijava.event.EventHandler;
@@ -66,13 +65,6 @@ public class DefaultAppService extends AbstractSingletonService<App> implements
 
 	// -- AppService methods --
 
-	@Override
-	public App getApp() {
-		final List<App> appList = getInstances();
-		if (appList == null || appList.isEmpty()) return null;
-		return appList.get(0);
-	}
-
 	@Override
 	public App getApp(final String name) {
 		return apps().get(name);
@@ -83,13 +75,6 @@ public Map<String, App> getApps() {
 		return apps();
 	}
 
-	// -- SingletonService methods --
-
-	@Override
-	public Class<App> getPluginType() {
-		return App.class;
-	}
-
 	// -- Event handlers --
 
 	@EventHandler(key = "org.scijava.app.AppService#about")