Merge pull request #7 from byteground/master

don't use a default port, find a free one

src/main/java/jmockmongo/MockMongo.java

@@ -19,8 +19,10 @@
 package jmockmongo;
 
 import java.net.InetSocketAddress;
+import java.net.ServerSocket;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.concurrent.Executors;
+import java.io.IOException;
 
 import jmockmongo.commands.Count;
 import jmockmongo.commands.DbStats;
@@ -48,25 +50,46 @@
 public class MockMongo {
 
 	/**
-	 * the port JMockMongo listens to by default. This is different from the
-	 * real MongoDB default port to reduce the risk of accidentally connecting
-	 * test code to real databases.
-	 * 
+	 * Utility method to find a free port
 	 */
-	public static final int DEFAULT_PORT = 2307;
+	public static int anyPort() {
+		try {
+			ServerSocket socket = new ServerSocket(0);
+			int port = socket.getLocalPort();
+			socket.close();
+			return port;
+		} catch (IOException e) {
+			return 2307;
+		}
+	}
 
-	/**
-	 * The MongoURI to connect to the default JMockMongo port (on localhost)
-	 */
-	public static final MongoURI DEFAULT_URI = new MongoURI(
-			"mongodb://0.0.0.0:" + DEFAULT_PORT);
+	private int port;
+
+	private MongoURI uri;
 
 	private ChannelGroup channels;
 
 	private ServerBootstrap bootstrap;
 
 	private ConcurrentHashMap<String, MockDB> data;
 
+	MockMongo() {
+		this(MockMongo.anyPort());
+	}
+
+	MockMongo(int port) {
+	  this.port = port;
+	  this.uri = new MongoURI("mongodb://0.0.0.0:" + port);
+	}
+
+	int getPort() {
+		return port;
+	}
+
+	MongoURI getMongoURI() {
+		return uri;
+	}
+
 	MockDB getDB(String database) {
 		return data.get(database);
 	}
@@ -99,6 +122,8 @@ MockDBCollection getCollection(String database, String collectionName) {
 		return db.getCollection(collectionName);
 	}
 
+
+
 	public void start() {
 		data = new ConcurrentHashMap<String, MockDB>();
 		final ChannelFactory factory = new NioServerSocketChannelFactory(
@@ -144,7 +169,7 @@ public void channelOpen(ChannelHandlerContext ctx,
 			}
 		});
 
-		channels.add(bootstrap.bind(new InetSocketAddress(DEFAULT_PORT)));
+		channels.add(bootstrap.bind(new InetSocketAddress(port)));
 	}
 
 	public void stop() {

src/main/java/jmockmongo/MockMongoTestCaseSupport.java

@@ -39,16 +39,18 @@ public abstract class MockMongoTestCaseSupport extends TestCase {
 	protected void setUp() throws Exception {
 		// make sure we cannot connect before this
 		// (this could mean a real server is running on our port)
+
+		mockMongo = new MockMongo();
+
 		try {
-			new DBPort(new ServerAddress("0.0.0.0", MockMongo.DEFAULT_PORT))
+			new DBPort(new ServerAddress("0.0.0.0", mockMongo.getPort()))
 					.ensureOpen();
 			fail("something is already listening at the Mongo port! Is a real mongo process running?");
 		} catch (IOException e) {
 		}
-
-		mockMongo = new MockMongo();
 		mockMongo.start();
-		mongo = new Mongo(MockMongo.DEFAULT_URI);
+
+		mongo = new Mongo(mockMongo.getMongoURI());
 	}
 
 	@Override

src/test/java/jmockmongo/MockMongoTest.java

@@ -36,10 +36,10 @@ public void testStartStop() throws UnknownHostException, MongoException,
 
 		MockMongo mongo = new MockMongo();
 		mongo.start();
-		new Mongo(MockMongo.DEFAULT_URI).getDatabaseNames();
+		new Mongo(mongo.getMongoURI()).getDatabaseNames();
 		mongo.stop();
 		try {
-			new Mongo(MockMongo.DEFAULT_URI).getDatabaseNames();
+			new Mongo(mongo.getMongoURI()).getDatabaseNames();
 			fail("should have stopped");
 		} catch (MongoException e) {
 		}
@@ -48,10 +48,11 @@ public void testStartStop() throws UnknownHostException, MongoException,
 	public void testCannotBind() throws MongoException, InterruptedException,
 			IOException {
 
-		ServerSocket socket = new ServerSocket(MockMongo.DEFAULT_PORT);
+		int port = MockMongo.anyPort();
+		ServerSocket socket = new ServerSocket(port);
 		try {
 
-			MockMongo mongo = new MockMongo();
+			MockMongo mongo = new MockMongo(port);
 			mongo.start();
 			fail("should have failed to start, because the server port is not available");
 		} catch (ChannelException e) {