Using getRefsByPrefix with multiple prefixes

Change-Id: I9901e733797bd661f2485cc42914ad01699617d3
Signed-off-by: Minh Thai <mthai@google.com>

org.eclipse.jgit/src/org/eclipse/jgit/api/ListBranchCommand.java

  */
 package org.eclipse.jgit.api;
 
+import static org.eclipse.jgit.lib.Constants.HEAD;
+import static org.eclipse.jgit.lib.Constants.R_HEADS;
+import static org.eclipse.jgit.lib.Constants.R_REMOTES;
+
 import java.io.IOException;
 import java.text.MessageFormat;
 import java.util.ArrayList;
 import org.eclipse.jgit.api.errors.JGitInternalException;
 import org.eclipse.jgit.api.errors.RefNotFoundException;
 import org.eclipse.jgit.internal.JGitText;
-import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.Repository;
 			Collection<Ref> refs = new ArrayList<>();
 
 			// Also return HEAD if it's detached
-			Ref head = repo.exactRef(Constants.HEAD);
-			if (head != null && head.getLeaf().getName().equals(Constants.HEAD))
+			Ref head = repo.exactRef(HEAD);
+			if (head != null && head.getLeaf().getName().equals(HEAD)) {
 				refs.add(head);
+			}
 
 			if (listMode == null) {
-				refs.addAll(getRefs(Constants.R_HEADS));
+				refs.addAll(repo.getRefDatabase().getRefsByPrefix(R_HEADS));
 			} else if (listMode == ListMode.REMOTE) {
-				refs.addAll(getRefs(Constants.R_REMOTES));
+				refs.addAll(repo.getRefDatabase().getRefsByPrefix(R_REMOTES));
 			} else {
-				refs.addAll(getRefs(Constants.R_HEADS));
-				refs.addAll(getRefs(Constants.R_REMOTES));
+				refs.addAll(repo.getRefDatabase().getRefsByPrefix(R_HEADS,
+						R_REMOTES));
 			}
 			resultRefs = new ArrayList<>(filterRefs(refs));
 		} catch (IOException e) {
 		this.containsCommitish = containsCommitish;
 		return this;
 	}
-
-	private Collection<Ref> getRefs(String prefix) throws IOException {
-		return repo.getRefDatabase().getRefsByPrefix(prefix);
-	}
 }

org.eclipse.jgit/src/org/eclipse/jgit/transport/UploadPack.java

 			refsToSend = getAdvertisedOrDefaultRefs();
 		} else {
 			refsToSend = new HashMap<>();
-			for (String refPrefix : req.getRefPrefixes()) {
-				for (Ref ref : db.getRefDatabase().getRefsByPrefix(refPrefix)) {
-					refsToSend.put(ref.getName(), ref);
-				}
+			String[] prefixes = req.getRefPrefixes().toArray(new String[0]);
+			for (Ref ref : db.getRefDatabase().getRefsByPrefix(prefixes)) {
+				refsToSend.put(ref.getName(), ref);
 			}
 		}
 		if (req.getSymrefs()) {