NoteMap implements Iterable<Note>

We will need to iterate over all notes of a NoteMap, at least this will be
needed for testing purposes. This change also implied making the Note class
public.

Change-Id: I9b0639f9843f457ee9de43504b2499a673cd0e77
Signed-off-by: Sasa Zivkov <sasa.zivkov@sap.com>

org.eclipse.jgit.test/tst/org/eclipse/jgit/notes/NoteMapTest.java

@@ -52,6 +52,7 @@
 import static org.junit.Assert.assertTrue;
 
 import java.io.IOException;
+import java.util.Iterator;
 
 import org.eclipse.jgit.junit.TestRepository;
 import org.eclipse.jgit.lib.CommitBuilder;
@@ -444,6 +445,83 @@ public void testRemoveDeletesTreeFanout2_38() throws Exception {
 		assertEquals("empty tree", empty, n.getTree());
 	}
 
+	public void testIteratorEmptyMap() {
+		Iterator<Note> it = NoteMap.newEmptyMap().iterator();
+		assertFalse(it.hasNext());
+	}
+
+	public void testIteratorFlatTree() throws Exception {
+		RevBlob a = tr.blob("a");
+		RevBlob b = tr.blob("b");
+		RevBlob data1 = tr.blob("data1");
+		RevBlob data2 = tr.blob("data2");
+		RevBlob nonNote = tr.blob("non note");
+
+		RevCommit r = tr.commit() //
+				.add(a.name(), data1) //
+				.add(b.name(), data2) //
+				.add("nonNote", nonNote) //
+				.create();
+		tr.parseBody(r);
+
+		Iterator it = NoteMap.read(reader, r).iterator();
+		assertEquals(2, count(it));
+	}
+
+	public void testIteratorFanoutTree2_38() throws Exception {
+		RevBlob a = tr.blob("a");
+		RevBlob b = tr.blob("b");
+		RevBlob data1 = tr.blob("data1");
+		RevBlob data2 = tr.blob("data2");
+		RevBlob nonNote = tr.blob("non note");
+
+		RevCommit r = tr.commit() //
+				.add(fanout(2, a.name()), data1) //
+				.add(fanout(2, b.name()), data2) //
+				.add("nonNote", nonNote) //
+				.create();
+		tr.parseBody(r);
+
+		Iterator it = NoteMap.read(reader, r).iterator();
+		assertEquals(2, count(it));
+	}
+
+	public void testIteratorFanoutTree2_2_36() throws Exception {
+		RevBlob a = tr.blob("a");
+		RevBlob b = tr.blob("b");
+		RevBlob data1 = tr.blob("data1");
+		RevBlob data2 = tr.blob("data2");
+		RevBlob nonNote = tr.blob("non note");
+
+		RevCommit r = tr.commit() //
+				.add(fanout(4, a.name()), data1) //
+				.add(fanout(4, b.name()), data2) //
+				.add("nonNote", nonNote) //
+				.create();
+		tr.parseBody(r);
+
+		Iterator it = NoteMap.read(reader, r).iterator();
+		assertEquals(2, count(it));
+	}
+
+	public void testIteratorFullyFannedOut() throws Exception {
+		RevBlob a = tr.blob("a");
+		RevBlob b = tr.blob("b");
+		RevBlob data1 = tr.blob("data1");
+		RevBlob data2 = tr.blob("data2");
+		RevBlob nonNote = tr.blob("non note");
+
+		RevCommit r = tr.commit() //
+				.add(fanout(38, a.name()), data1) //
+				.add(fanout(38, b.name()), data2) //
+				.add("nonNote", nonNote) //
+				.create();
+		tr.parseBody(r);
+
+		Iterator it = NoteMap.read(reader, r).iterator();
+		assertEquals(2, count(it));
+	}
+
 	private RevCommit commitNoteMap(NoteMap map) throws IOException {
 		tr.tick(600);
 
@@ -469,4 +547,13 @@ private static String fanout(int prefix, String name) {
 		}
 		return r.toString();
 	}
+
+	private static int count(Iterator it) {
+		int c = 0;
+		while (it.hasNext()) {
+			c++;
+			it.next();
+		}
+		return c;
+	}
 }

org.eclipse.jgit/src/org/eclipse/jgit/notes/Note.java

@@ -47,7 +47,7 @@
 import org.eclipse.jgit.lib.ObjectId;
 
 /** In-memory representation of a single note attached to one object. */
-class Note extends ObjectId {
+public class Note extends ObjectId {
 	private ObjectId data;
 
 	/**
@@ -63,7 +63,8 @@ class Note extends ObjectId {
 		data = noteData;
 	}
 
-	ObjectId getData() {
+	/** @return the note content */
+	public ObjectId getData() {
 		return data;
 	}
 

org.eclipse.jgit/src/org/eclipse/jgit/notes/NoteMap.java

@@ -44,6 +44,7 @@
 package org.eclipse.jgit.notes;
 
 import java.io.IOException;
+import java.util.Iterator;
 
 import org.eclipse.jgit.errors.CorruptObjectException;
 import org.eclipse.jgit.errors.IncorrectObjectTypeException;
@@ -52,6 +53,7 @@
 import org.eclipse.jgit.lib.AbbreviatedObjectId;
 import org.eclipse.jgit.lib.AnyObjectId;
 import org.eclipse.jgit.lib.Constants;
+import org.eclipse.jgit.lib.MutableObjectId;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.ObjectReader;
@@ -66,7 +68,7 @@
  * is not released by this class. The caller should arrange for releasing the
  * shared {@code ObjectReader} at the proper times.
  */
-public class NoteMap {
+public class NoteMap implements Iterable<Note> {
 	/**
 	 * Construct a new empty note map.
 	 *
@@ -165,6 +167,18 @@ private NoteMap(ObjectReader reader) {
 		this.reader = reader;
 	}
 
+	/**
+	 * @return an iterator that iterates over notes of this NoteMap. Non note
+	 *         entries are ignored by this iterator.
+	 */
+	public Iterator<Note> iterator() {
+		try {
+			return root.iterator(new MutableObjectId(), reader);
+		} catch (IOException e) {
+			throw new RuntimeException(e);
+		}
+	}
+
 	/**
 	 * Lookup a note for a specific ObjectId.
 	 *