Merge branch 'ui-split'

This branch migrates the UI subsystem from ImageJ core.

This system has nothing specifically to do with images, and requires no
additional dependencies.

See:
https://github.com/imagej/imagej/tree/imagej-2.0.0-beta-7.9/core/ui

Author: ctrueden

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

@@ -31,7 +31,10 @@
 
 package org.scijava.app;
 
+import java.io.File;
+
 import org.scijava.plugin.AbstractRichPlugin;
+import org.scijava.util.AppUtils;
 import org.scijava.util.Manifest;
 import org.scijava.util.POM;
 
@@ -48,6 +51,11 @@ public abstract class AbstractApp extends AbstractRichPlugin implements App {
 	/** JAR manifest with metadata about the application. */
 	private Manifest manifest;
 
+	@Override
+	public String getTitle() {
+		return getInfo().getName();
+	}
+
 	@Override
 	public String getVersion() {
 		return getPOM() == null ? "Unknown" : getPOM().getVersion();
@@ -90,4 +98,14 @@ public String getInfo(boolean mem) {
 		return sb.toString();
 	}
 
+	@Override
+	public String getSystemProperty() {
+		return getInfo().getName().toLowerCase() + ".dir";
+	}
+
+	@Override
+	public File getBaseDirectory() {
+		return AppUtils.getBaseDirectory(getSystemProperty(), getClass(), null);
+	}
+
 }

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

@@ -31,8 +31,11 @@
 
 package org.scijava.app;
 
+import java.io.File;
+
 import org.scijava.plugin.Plugin;
 import org.scijava.plugin.RichPlugin;
+import org.scijava.plugin.SingletonPlugin;
 import org.scijava.util.Manifest;
 import org.scijava.util.POM;
 
@@ -50,7 +53,7 @@
  * @see Plugin
  * @see AppService
  */
-public interface App extends RichPlugin {
+public interface App extends RichPlugin, SingletonPlugin {
 
 	/** Gets the title of the application. */
 	String getTitle();
@@ -90,4 +93,17 @@ public interface App extends RichPlugin {
 	 */
 	String getInfo(boolean mem);
 
+	/**
+	 * A system property which, if set, overrides the base directory of the
+	 * application.
+	 */
+	String getSystemProperty();
+
+	/**
+	 * Gets the application's root directory. If the application's system property
+	 * is set, it is used. Otherwise, we scan up the tree from this class for a
+	 * suitable directory.
+	 */
+	File getBaseDirectory();
+
 }

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

@@ -33,14 +33,17 @@
 
 import java.util.Map;
 
-import org.scijava.service.SciJavaService;
+import org.scijava.plugin.SingletonService;
 
 /**
  * Interface for application-level functionality.
  * 
  * @author Curtis Rueden
  */
-public interface AppService extends SciJavaService {
+public interface AppService extends SingletonService<App> {
+
+	/** Gets the foremost application (the one with the highest priority). */
+	App getApp();
 
 	/** Gets an application by name. */
 	App getApp(final String name);

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

@@ -37,11 +37,10 @@
 import java.util.Map;
 
 import org.scijava.log.LogService;
+import org.scijava.plugin.AbstractSingletonService;
 import org.scijava.plugin.Parameter;
 import org.scijava.plugin.Plugin;
-import org.scijava.plugin.PluginInfo;
 import org.scijava.plugin.PluginService;
-import org.scijava.service.AbstractService;
 import org.scijava.service.Service;
 
 /**
@@ -50,7 +49,7 @@
  * @author Curtis Rueden
  */
 @Plugin(type = Service.class)
-public class DefaultAppService extends AbstractService implements AppService {
+public class DefaultAppService extends AbstractSingletonService<App> implements AppService {
 
 	@Parameter
 	private LogService log;
@@ -63,43 +62,51 @@ public class DefaultAppService extends AbstractService implements AppService {
 
 	// -- 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);
+		return apps().get(name);
 	}
 
 	@Override
 	public Map<String, App> getApps() {
-		return apps;
+		return apps();
 	}
 
-	// -- Service methods --
+	// -- SingletonService methods --
 
 	@Override
-	public void initialize() {
-		apps = Collections.unmodifiableMap(discoverApps());
-		log.info("Found " + apps.size() + " applications.");
-		super.initialize();
+	public Class<App> getPluginType() {
+		return App.class;
 	}
 
-	// -- Helper methods --
+	// -- Helper methods - lazy initialization --
+
+	/** Gets {@link #apps}, initializing if necessary. */
+	private Map<String, App> apps() {
+		if (apps == null) initApps();
+		return apps;
+	}
 
-	/** Discovers applications. */
-	private HashMap<String, App> discoverApps() {
+	/** Initializes {@link #apps}. */
+	private synchronized void initApps() {
+		if (apps != null) return; // already initialized
 		final HashMap<String, App> map = new HashMap<String, App>();
 
-		final List<PluginInfo<App>> infos =
-			pluginService.getPluginsOfType(App.class);
-		for (final PluginInfo<App> info : infos) {
-			final App app = pluginService.createInstance(info);
-			if (app == null) continue;
-			final String name = info.getName();
+		for (final App app : getInstances()) {
+			final String name = app.getInfo().getName();
 			if (!map.containsKey(name)) {
 				// no (higher-priority) app with the same name exists
 				map.put(name, app);
 			}
 		}
-		return map;
+		apps = Collections.unmodifiableMap(map);
 	}
 
 }

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

@@ -31,6 +31,7 @@
 
 package org.scijava.app;
 
+import org.scijava.Priority;
 import org.scijava.plugin.Plugin;
 
 /**
@@ -39,16 +40,12 @@
  * @author Curtis Rueden
  * @see AppService
  */
-@Plugin(type = App.class, name = SciJavaApp.NAME)
+@Plugin(type = App.class, name = SciJavaApp.NAME,
+	priority = Priority.LOW_PRIORITY)
 public class SciJavaApp extends AbstractApp {
 
 	public static final String NAME = "SciJava";
 
-	@Override
-	public String getTitle() {
-		return NAME;
-	}
-
 	@Override
 	public String getGroupId() {
 		return "org.scijava";

src/main/java/org/scijava/io/console/OpenArgument.java

@@ -0,0 +1,87 @@
+/*
+ * #%L
+ * SciJava Common shared library for SciJava software.
+ * %%
+ * Copyright (C) 2009 - 2014 Board of Regents of the University of
+ * Wisconsin-Madison, Broad Institute of MIT and Harvard, and Max Planck
+ * Institute of Molecular Cell Biology and Genetics.
+ * %%
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * 
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ * #L%
+ */
+
+package org.scijava.io.console;
+
+import java.io.IOException;
+import java.util.LinkedList;
+
+import org.scijava.console.AbstractConsoleArgument;
+import org.scijava.console.ConsoleArgument;
+import org.scijava.display.DisplayService;
+import org.scijava.io.IOService;
+import org.scijava.log.LogService;
+import org.scijava.plugin.Parameter;
+import org.scijava.plugin.Plugin;
+
+/**
+ * Handles the {@code --open} command line argument.
+ * 
+ * @author Curtis Rueden
+ */
+@Plugin(type = ConsoleArgument.class)
+public class OpenArgument extends AbstractConsoleArgument {
+
+	@Parameter
+	private IOService ioService;
+
+	@Parameter
+	private DisplayService displayService;
+
+	@Parameter
+	private LogService log;
+
+	// -- ConsoleArgument methods --
+
+	@Override
+	public void handle(final LinkedList<String> args) {
+		if (!supports(args)) return;
+
+		args.removeFirst(); // --open
+		final String source = args.removeFirst();
+
+		try {
+			final Object o = ioService.open(source);
+			displayService.createDisplay(o);
+		}
+		catch (IOException exc) {
+			log.error(exc);
+		}
+	}
+
+	// -- Typed methods --
+
+	@Override
+	public boolean supports(final LinkedList<String> args) {
+		return args != null && args.size() >= 2 && args.getFirst().equals("--open");
+	}
+
+}