Record location of tracked objects, too

We will need this later, because we really want to verify, when
compiling usage statistics, which update site (if any) the relevant file
came from. If we cannot deduce the update site, we don't care about the
object's usage, because it is not part of the "known ecosystem" of
modules etc.

Author: ctrueden

src/main/java/org/scijava/usage/DefaultUsageService.java

@@ -35,6 +35,7 @@
 import java.util.Map;
 
 import org.scijava.Identifiable;
+import org.scijava.Locatable;
 import org.scijava.event.EventHandler;
 import org.scijava.module.ModuleInfo;
 import org.scijava.module.event.ModuleExecutedEvent;
@@ -71,12 +72,13 @@ public void clearStats() {
 
 	@Override
 	public UsageStats getUsage(final Object o) {
-		if (!(o instanceof Identifiable)) {
-			// only track objects with an identifier
+		if (!(o instanceof Identifiable) || !(o instanceof Locatable)) {
+			// only track objects with an identifier and a location
 			return null;
 		}
 		final String id = ((Identifiable) o).getIdentifier();
-		if (!stats.containsKey(id)) stats.put(id, new UsageStats(id));
+		final String url = ((Locatable) o).getLocation();
+		if (!stats.containsKey(id)) stats.put(id, new UsageStats(id, url));
 		return stats.get(id);
 	}
 

src/main/java/org/scijava/usage/UsageStats.java

@@ -32,22 +32,27 @@
 package org.scijava.usage;
 
 import org.scijava.Identifiable;
+import org.scijava.Locatable;
 
 /**
  * Data structure storing usage statistics for a particular identifier.
  * 
  * @author Curtis Rueden
  */
-public class UsageStats implements Identifiable {
+public class UsageStats implements Identifiable, Locatable {
 
 	/** The object's unique identifier. */
 	private String id;
 
+	/** This object's location URL. */
+	private String url;
+
 	/** Number of times the object was used. */
 	private long count;
 
-	public UsageStats(final String id) {
+	public UsageStats(final String id, final String url) {
 		this.id = id;
+		this.url = url;
 	}
 
 	/** Gets the number of times the object has been used. */
@@ -67,4 +72,11 @@ public String getIdentifier() {
 		return id;
 	}
 
+	// -- Locatable methods --
+
+	@Override
+	public String getLocation() {
+		return url;
+	}
+
 }