Add a stub for a GroupInvitationManager

briar-api/src/org/briarproject/api/sharing/InvitationItem.java

@@ -1,32 +1,36 @@
 package org.briarproject.api.sharing;
 
-import org.briarproject.api.contact.Contact;
+import org.briarproject.api.nullsafety.NotNullByDefault;
+import org.briarproject.api.sync.GroupId;
 
-import java.util.Collection;
+import javax.annotation.concurrent.ThreadSafe;
 
-public class InvitationItem {
+@ThreadSafe
+@NotNullByDefault
+public abstract class InvitationItem {
 
 	private final Shareable shareable;
 	private final boolean subscribed;
-	private final Collection<Contact> newSharers;
-
-	public InvitationItem(Shareable shareable, boolean subscribed,
-			Collection<Contact> newSharers) {
 
+	public InvitationItem(Shareable shareable, boolean subscribed) {
 		this.shareable = shareable;
 		this.subscribed = subscribed;
-		this.newSharers = newSharers;
 	}
 
 	public Shareable getShareable() {
 		return shareable;
 	}
 
+	public GroupId getId() {
+		return shareable.getId();
+	}
+
+	public String getName() {
+		return shareable.getName();
+	}
+
 	public boolean isSubscribed() {
 		return subscribed;
 	}
 
-	public Collection<Contact> getNewSharers() {
-		return newSharers;
-	}
 }

briar-api/src/org/briarproject/api/sharing/Shareable.java

@@ -8,4 +8,7 @@ public interface Shareable {
 	GroupId getId();
 
 	Group getGroup();
+
+	String getName();
+
 }

briar-api/src/org/briarproject/api/sharing/SharingInvitationItem.java

@@ -0,0 +1,22 @@
+package org.briarproject.api.sharing;
+
+import org.briarproject.api.contact.Contact;
+
+import java.util.Collection;
+
+public class SharingInvitationItem extends InvitationItem {
+
+	private final Collection<Contact> newSharers;
+
+	public SharingInvitationItem(Shareable shareable, boolean subscribed,
+			Collection<Contact> newSharers) {
+		super(shareable, subscribed);
+
+		this.newSharers = newSharers;
+	}
+
+	public Collection<Contact> getNewSharers() {
+		return newSharers;
+	}
+
+}

briar-api/src/org/briarproject/api/sharing/SharingManager.java

@@ -38,7 +38,7 @@ public interface SharingManager<S extends Shareable> extends MessageTracker {
 	/**
 	 * Returns all invitations to groups.
 	 */
-	Collection<InvitationItem> getInvitations() throws DbException;
+	Collection<SharingInvitationItem> getInvitations() throws DbException;
 
 	/**
 	 * Returns all contacts who are sharing the given group with us.