Extract the capability parsing logic in {Upload,Receive}Pack

Change-Id: I7ac4e0ae98872a74b01162b5ca936fb15e2f8cff

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

  * Implements the server side of a push connection, receiving objects.
  */
 public class ReceivePack {
+	/** Data in the first line of a request, the line itself plus capabilities. */
+	public static class FirstLine {
+		private final String line;
+		private final Set<String> capabilities;
+
+		/**
+		 * Parse the first line of a receive-pack request.
+		 *
+		 * @param line
+		 *            line from the client.
+		 */
+		public FirstLine(String line) {
+			final HashSet<String> caps = new HashSet<String>();
+			final int nul = line.indexOf('\0');
+			if (nul >= 0) {
+				for (String c : line.substring(nul + 1).split(" "))
+					caps.add(c);
+			}
+			this.line = line.substring(0, nul);
+			this.capabilities = Collections.unmodifiableSet(caps);
+		}
+
+		/** @return non-capabilities part of the line. */
+		public String getLine() {
+			return line;
+		}
+
+		/** @return capabilities parsed from the line. */
+		public Set<String> getCapabilities() {
+			return capabilities;
+		}
+	}
+
 	/** Database we write the stored objects into. */
 	private final Repository db;
 
 			pckOut = new PacketLineOut(rawOut);
 			pckOut.setFlushOnEnd(false);
 
-			enabledCapabilities = new HashSet<String>();
 			commands = new ArrayList<ReceiveCommand>();
 
 			service();
 				break;
 
 			if (commands.isEmpty()) {
-				final int nul = line.indexOf('\0');
-				if (nul >= 0) {
-					for (String c : line.substring(nul + 1).split(" "))
-						enabledCapabilities.add(c);
-					line = line.substring(0, nul);
-				}
+				final FirstLine firstLine = new FirstLine(line);
+				enabledCapabilities = firstLine.getCapabilities();
+				line = firstLine.getLine();
 			}
 
 			if (line.length() < 83) {

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

 		ANY;
 	}
 
+	/** Data in the first line of a request, the line itself plus options. */
+	public static class FirstLine {
+		private final String line;
+		private final Set<String> options;
+
+		/**
+		 * Parse the first line of a receive-pack request.
+		 *
+		 * @param line
+		 *            line from the client.
+		 */
+		public FirstLine(String line) {
+			if (line.length() > 45) {
+				final HashSet<String> opts = new HashSet<String>();
+				String opt = line.substring(45);
+				if (opt.startsWith(" "))
+					opt = opt.substring(1);
+				for (String c : opt.split(" "))
+					opts.add(c);
+				this.line = line.substring(0, 45);
+				this.options = Collections.unmodifiableSet(opts);
+			} else {
+				this.line = line;
+				this.options = Collections.emptySet();
+			}
+		}
+
+		/** @return non-capabilities part of the line. */
+		public String getLine() {
+			return line;
+		}
+
+		/** @return options parsed from the line. */
+		public Set<String> getOptions() {
+			return options;
+		}
+	}
+
 	/** Database we read the objects from. */
 	private final Repository db;
 
 	private PreUploadHook preUploadHook = PreUploadHook.NULL;
 
 	/** Capabilities requested by the client. */
-	private final Set<String> options = new HashSet<String>();
+	private Set<String> options;
 
 	/** Raw ObjectIds the client has asked for, before validating them. */
 	private final Set<ObjectId> wantIds = new HashSet<ObjectId>();
 				throw new PackProtocolException(MessageFormat.format(JGitText.get().expectedGot, "want", line));
 
 			if (isFirst && line.length() > 45) {
-				String opt = line.substring(45);
-				if (opt.startsWith(" "))
-					opt = opt.substring(1);
-				for (String c : opt.split(" "))
-					options.add(c);
-				line = line.substring(0, 45);
+				final FirstLine firstLine = new FirstLine(line);
+				options = firstLine.getOptions();
+				line = firstLine.getLine();
 			}
 
 			wantIds.add(ObjectId.fromString(line.substring(5)));