Refactor sockets to allow for port=0

If port=0 the OS picks any available port. This is useful in
ServerConnectionTest where there before was an ugly hack to try
different ports.

cardshifter-server/src/main/java/com/cardshifter/server/model/MainServer.java

@@ -69,8 +69,8 @@ public Server start() {
 		try {
 			logger.info("Starting Server...");
 
-			server.addConnections(new ServerSock(server, config.getPortSocket()));
-			server.addConnections(new ServerWeb(server, config.getPortWebsocket()));
+			server.addConnections(new ServerSock(server, config));
+			server.addConnections(new ServerWeb(server, config));
 
 			logger.info("Starting Console...");
 			CommandHandler commandHandler = server.getCommandHandler();

cardshifter-server/src/main/java/com/cardshifter/server/model/ServerSock.java

@@ -8,6 +8,7 @@
 import java.util.concurrent.Future;
 import java.util.concurrent.atomic.AtomicInteger;
 
+import com.cardshifter.server.main.ServerConfiguration;
 import org.apache.log4j.LogManager;
 import org.apache.log4j.Logger;
 
@@ -22,11 +23,22 @@ public class ServerSock implements ConnectionHandler {
 	private final Server server;
 	private final Thread thread;
 	private final ServerSocket serverSocket;
-
-	public ServerSock(Server server, int port) throws IOException {
+
+	/**
+	 * Constructor.
+	 * @param server Server instance
+	 * @param config Uses the value of {@code config.getPortSocket} as port. If {@code port == 0} any available port is
+	 *                  used and the real port number is set in {@code config} before returning.
+	 * @throws IOException
+	 */
+	public ServerSock(Server server, ServerConfiguration config) throws IOException {
 		this.server = server;
 		this.executor = Executors.newCachedThreadPool(r -> new Thread(r, "Conn-" + threadCounter.getAndIncrement()));
-		this.serverSocket = new ServerSocket(port);
+
+		// If port = 0, use any open port. Set the config port to the real port used.
+		this.serverSocket = new ServerSocket(config.getPortSocket());
+		config.setPortSocket(serverSocket.getLocalPort());
+
 		this.thread = new Thread(this::run);
 	}
 

cardshifter-server/src/main/java/com/cardshifter/server/model/ServerWeb.java

@@ -1,17 +1,12 @@
 package com.cardshifter.server.model;
 
-import java.io.ByteArrayInputStream;
-import java.io.IOException;
 import java.net.InetSocketAddress;
-import java.util.Arrays;
 import java.util.Map;
 import java.util.concurrent.ConcurrentHashMap;
 
 import com.cardshifter.api.CardshifterSerializationException;
-import com.cardshifter.api.messages.Message;
 import com.cardshifter.api.serial.ByteTransformer;
-import com.cardshifter.server.clients.Base64Utils;
-import com.fasterxml.jackson.databind.ObjectMapper;
+import com.cardshifter.server.main.ServerConfiguration;
 import net.zomis.cardshifter.ecs.usage.CardshifterIO;
 import org.apache.log4j.LogManager;
 import org.apache.log4j.Logger;
@@ -26,9 +21,16 @@ public class ServerWeb implements ConnectionHandler {
 	private static final Logger logger = LogManager.getLogger(ServerWeb.class);
 
 	private final InnerServer websocketServer;
-
-	public ServerWeb(Server server, int port) {
-		this.websocketServer = new InnerServer(server, port);
+
+	/**
+	 * Constructor.
+	 * @param server Server instance
+	 * @param config Uses the value of {@code config.getPortWebsocket} as port. If {@code port == 0} any available port
+	 *                  is used and the real port number is set in {@code config} before returning.
+	 */
+	public ServerWeb(Server server, ServerConfiguration config) {
+		this.websocketServer = new InnerServer(server, config.getPortWebsocket());
+		config.setPortWebsocket(websocketServer.getPort());
 	}
 
 	private static class InnerServer extends WebSocketServer {

cardshifter-server/src/test/java/com/cardshifter/server/main/ServerConnectionTest.java

@@ -63,26 +63,15 @@ public void setup() throws IOException, InterruptedException {
 		PropertyConfigurator.configure(getClass().getResourceAsStream("log4j.properties"));
 		ServerConfiguration config = ServerConfiguration.defaults();
 
-		int basePortSocket = config.getPortSocket();
-		int basePortWebsocket = config.getPortWebsocket();
-
-		// The ports might be in use by another instance or application
-		// Could use port = 0, but would need access to the ServerSocket to get the real port number
-		for (int i = 0; i < MAX_SERVER_PORT_TRY; i++) {
-			config.setPortSocket(basePortSocket + i * 10);
-			config.setPortWebsocket(basePortWebsocket + i * 10);
-
-			main = new MainServer(config);
-			main.getMods().loadExternal(Paths.get("../extra-resources/groovy"));
-			server = main.start();
-
-			if (server.getClients().size() > 0) {
-				break;
-			}
-		}
+		// Use any available port
+		config.setPortSocket(0);
+		config.setPortWebsocket(0);
+
+		main = new MainServer(config);
+		main.getMods().loadExternal(Paths.get("../extra-resources/groovy"));
+		server = main.start();
 
-		assertTrue("Server did not start correctly after " + MAX_SERVER_PORT_TRY + " retries.",
-				   server.getClients().size() > 0);
+		assertTrue("Server should start correctly.", server.getClients().size() > 0);
 
 		socketPort = config.getPortSocket();
 		client1 = createTestClient();