test github

build.gradle

@@ -5,7 +5,7 @@ plugins {
 }
 
 group 'me.bvn13'
-version '1.2.1'
+version '1.2.8'
 
 repositories {
     mavenCentral()
@@ -16,9 +16,6 @@ dependencies {
     // https://mvnrepository.com/artifact/org.slf4j/slf4j-api
     implementation group: 'org.slf4j', name: 'slf4j-api', version: '1.7.35'
 
-    // https://mvnrepository.com/artifact/commons-io/commons-io
-    implementation group: 'commons-io', name: 'commons-io', version: '2.11.0'
-
     // https://mvnrepository.com/artifact/org.apache.commons/commons-lang3
     implementation group: 'org.apache.commons', name: 'commons-lang3', version: '3.12.0'
 
@@ -37,14 +34,18 @@ tasks.withType(Test).configureEach {
     maxParallelForks = 1
 }
 
+task sourceJar(type: Jar) {
+    from sourceSets.main.allJava
+}
+
 publishing {
     repositories {
         maven {
             name = "GitHubPackages"
             url = uri("https://maven.pkg.github.com/bvn13/sewy")
             credentials {
-                username = project.findProperty("gpr.user") ?: System.getenv("USERNAME")
-                password = project.findProperty("gpr.key") ?: System.getenv("TOKEN")
+                username = project.findProperty("gpr.user") ?: System.getenv("GITHUB_USER")
+                password = project.findProperty("gpr.key") ?: System.getenv("GITHUB_TOKEN")
             }
         }
     }
@@ -52,5 +53,12 @@ publishing {
         gpr(MavenPublication) {
             from(components.java)
         }
+//        mavenJava(MavenPublication) {
+//            from components.java
+//
+//            artifact sourceJar {
+//                classifier "sources"
+//            }
+//        }
     }
 }

src/main/java/me/bvn13/sewy/AbstractClientListener.java

@@ -47,7 +47,7 @@ public abstract class AbstractClientListener implements Runnable {
             this.in = socket.getInputStream();
             log.debug("BufferedReader successfully created");
             log.debug("PrintWriter successfully created");
-            out = socket.getOutputStream();
+            this.out = socket.getOutputStream();
             log.debug("OutputStream successfully created");
         } catch (IOException e) {
             throw new RuntimeException(e);
@@ -63,9 +63,10 @@ public abstract class AbstractClientListener implements Runnable {
 
     /**
      * Reads line (separated with '\n') from socket
+     *
      * @return the line read from socket
      */
-    public String readLine() {
+    public String readLine() throws IOException {
         final byte[] bytes = readBytes(getSeparator());
         final StringBuilder sb = new StringBuilder();
         for (byte aByte : bytes) {
@@ -78,56 +79,69 @@ public abstract class AbstractClientListener implements Runnable {
 
     /**
      * Reads data from socket until {@code separator} is encountered
+     *
      * @param separator byte to separate data portions
      * @return array of bytes read from socket
      */
-    public byte[] readBytes(byte separator) {
-        final List<Byte> data = new ArrayList<>(256);
-        try {
-            while (socket.isConnected()) {
-                byte[] portion = in.readNBytes(1);
-                if (portion == null || portion.length == 0 || portion[0] == separator) {
+    public byte[] readBytes(byte[] separator) throws IOException {
+        final List<Byte> data = new ArrayList<>(2048 * 2048);
+        List<Byte> buffer = new ArrayList<>(separator.length);
+        int separatorPosition = 0;
+        while (socket.isConnected() && !socket.isClosed()) {
+            byte[] portion = in.readNBytes(1);
+            if (portion == null || portion.length == 0) {
+                break;
+            }
+            if (portion[0] == separator[separatorPosition]) {
+                if (separatorPosition == separator.length - 1) {
                     break;
                 }
-                data.add(portion[0]);
+                separatorPosition++;
+                buffer.add(portion[0]);
+                continue;
+            } else {
+                separatorPosition = 0;
+                data.addAll(buffer);
+                buffer.clear();
             }
-            final byte[] bytes = new byte[data.size()];
-            int i = 0;
-            for (Byte aByte : data) {
-                bytes[i++] = aByte;
-            }
-            if (log.isTraceEnabled()) log.trace("Received: " + new String(bytes));
-            return bytes;
-        } catch (IOException e) {
-            throw new RuntimeException(e);
+            data.add(portion[0]);
         }
+        final byte[] bytes = new byte[data.size()];
+        int i = 0;
+        for (Byte aByte : data) {
+            bytes[i++] = aByte;
+        }
+        if (log.isTraceEnabled()) log.trace("Received {} bytes: {}", bytes.length, bytes);
+        return bytes;
     }
 
     /**
      * Writes line into socket ending with default separator '\n'.
      * Flushes after writing.
-     * @param bytes bytes to be sent into socket
+     *
+     * @param bytes     bytes to be sent into socket
      * @param separator byte to separate data portions
      */
-    public void writeBytes(byte[] bytes, byte separator) {
-        if (log.isTraceEnabled()) log.trace("Sending: " + new String(bytes));
-        try {
-            out.write(bytes);
-            out.write(separator);
-            out.flush();
-        } catch (IOException e) {
-            throw new RuntimeException(e);
-        }
+    public void writeBytes(byte[] bytes, byte[] separator) throws IOException {
+        if (log.isTraceEnabled()) log.trace("Sending {} bytes: {}", bytes.length, bytes);
+        out.write(bytes);
+        out.write(separator);
+        out.flush();
     }
 
     /**
      * Writes line into socket ending with default separator '\n'.
      * Flushes after writing.
+     *
      * @param data data to be sent into socket
      */
     public void writeLine(String data) {
         if (log.isTraceEnabled()) log.trace("Sending: " + data);
-        writeBytes(data.getBytes(), getSeparator());
+        try {
+            writeBytes(data.getBytes(), getSeparator());
+        } catch (Exception e) {
+            log.error("", e);
+        }
     }
 
     /**
@@ -139,12 +153,12 @@ public abstract class AbstractClientListener implements Runnable {
             out.close();
             in.close();
         } catch (IOException e) {
-            log.warn("Unable to close IN client buffer");
+            log.warn("Unable to close IN/OUT client buffer");
         }
         try {
             socket.close();
         } catch (IOException e) {
-            throw new RuntimeException(e);
+            log.warn("Unable to close socket");
         }
     }
 }

src/main/java/me/bvn13/sewy/Client.java

@@ -89,7 +89,16 @@ public class Client<T extends AbstractClientListener> {
      */
     public void stop() {
         log.debug("Stopping client");
-        client.stop();
+        if (client != null) {
+            client.stop();
+        }
+        try {
+            if (socket != null) {
+                socket.close();
+            }
+        } catch (IOException e) {
+            log.error("Failed to close socket");
+        }
         executor.shutdown();
     }
 
@@ -106,7 +115,11 @@ public class Client<T extends AbstractClientListener> {
      * @return the line read from socket
      */
     public String readLine() {
-        return client.readLine();
+        try {
+            return client.readLine();
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
     }
 
     /**
@@ -114,7 +127,7 @@ public class Client<T extends AbstractClientListener> {
      * @param separator
      * @return
      */
-    public byte[] readBytes(byte separator) {
+    public byte[] readBytes(byte[] separator) throws IOException {
         return client.readBytes(separator);
     }
 

src/main/java/me/bvn13/sewy/ClientListenerFactory.java

@@ -26,16 +26,16 @@ class ClientListenerFactory {
 
     /**
      * Creates client listener constructor
+     *
      * @param clientListenerClass class to be used as client listener
-     * @param <T> generic type
+     * @param <T>                 generic type
      * @return lambda method to create client listener
      */
     @SuppressWarnings("unchecked")
     static <T extends AbstractClientListener> Function<Socket, T> createClientListenerConstructor(Class clientListenerClass) {
 
-        if (clientListenerClass.getGenericSuperclass() == null
-                /*|| !clientListenerClass.getGenericSuperclass().equals(T.class)*/) {
-            throw new IllegalArgumentException("Wrong client listener of type: "+clientListenerClass.getName());
+        if (clientListenerClass.getGenericSuperclass() == null) {
+            throw new IllegalArgumentException("Wrong client listener of type: " + clientListenerClass.getName());
         }
 
         return (client) -> {

src/main/java/me/bvn13/sewy/CommandClient.java

@@ -19,10 +19,10 @@ import me.bvn13.sewy.command.AbstractCommand;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import java.io.IOException;
 import java.net.Socket;
 import java.util.function.Function;
 
-import static java.lang.String.format;
 import static me.bvn13.sewy.ClientListenerFactory.createClientListenerConstructor;
 
 /**
@@ -41,6 +41,7 @@ public class CommandClient extends Client<CommandClientListener> {
 
     /**
      * Starts to connect to server immediately
+     *
      * @param host host to connect to
      * @param port port to be used while connecting
      */
@@ -50,8 +51,9 @@ public class CommandClient extends Client<CommandClientListener> {
 
     /**
      * Starts to connect to server immediately
-     * @param host host to connect to
-     * @param port port to be used while connecting
+     *
+     * @param host                host to connect to
+     * @param port                port to be used while connecting
      * @param clientListenerClass client listener class describing protocol of communications
      */
     public CommandClient(String host, int port, Class clientListenerClass) {
@@ -60,8 +62,9 @@ public class CommandClient extends Client<CommandClientListener> {
 
     /**
      * Connects to server immediately
-     * @param host host to connect to
-     * @param port port to be used while connecting
+     *
+     * @param host                      host to connect to
+     * @param port                      port to be used while connecting
      * @param clientListenerConstructor to provide constructor for client listener (see {@link me.bvn13.sewy.Client#Client(java.lang.String, int, java.lang.Class)})
      */
     public CommandClient(String host, int port, Function<Socket, CommandClientListener> clientListenerConstructor) {
@@ -71,10 +74,12 @@ public class CommandClient extends Client<CommandClientListener> {
 
     /**
      * Sends command to server
+     *
      * @param command command to be sent
-     * @param <T> generic type
+     * @param <T>     generic type
+     * @throws IOException if any error occurred while sending
      */
-    public <T extends AbstractCommand> void send(T command) {
+    public <T extends AbstractCommand> void send(T command) throws IOException {
         log.debug("Start to send command: " + command);
         client.send(command);
     }

src/main/java/me/bvn13/sewy/CommandClientListener.java

@@ -18,6 +18,7 @@ package me.bvn13.sewy;
 import me.bvn13.sewy.command.AbstractCommand;
 import org.apache.commons.lang3.SerializationUtils;
 
+import java.io.IOException;
 import java.io.Serializable;
 import java.net.Socket;
 
@@ -39,34 +40,38 @@ public class CommandClientListener extends AbstractClientListener implements Abs
     public void run() {
         for (Thread.yield(); !socket.isConnected() && !socket.isClosed(); Thread.yield()) {
         }
-        while (socket.isConnected()) {
-            Thread.yield();
-            byte[] line = readBytes(getSeparator());
-            if (line == null || line.length == 0) {
-                continue;
-            }
-            final Object command;
+        while (socket.isConnected() && !socket.isClosed()) {
             try {
-                command = SerializationUtils.deserialize(line);
-            } catch (Throwable e) {
-                log.warn("Deserialization exception occurred!", e);
-                continue;
+                Thread.yield();
+                byte[] line = readBytes(getSeparator());
+                if (line == null || line.length == 0) {
+                    continue;
+                }
+                final Object command;
+                try {
+                    command = SerializationUtils.deserialize(line);
+                } catch (Throwable e) {
+                    log.warn("Deserialization exception occurred!", e);
+                    continue;
+                }
+                if (command == null) {
+                    continue;
+                }
+                if (!Sewy.getRegisteredDataTypes().contains(command.getClass())) {
+                    log.error("Unexpected command received");
+                    continue;
+                }
+                log.debug("Command received: " + command.getClass());
+                if (!(command instanceof AbstractCommand)) {
+                    log.warn("Incorrect command received: " + command);
+                    continue;
+                }
+                final Serializable response = onCommand((AbstractCommand) command);
+                log.debug(format("Response for %s is: %s", command, response));
+                writeBytes(SerializationUtils.serialize(response), getSeparator());
+            } catch (Exception e) {
+                log.error("Failed to communicate!", e);
             }
-            if (command == null) {
-                continue;
-            }
-            if (!Sewy.getRegisteredDataTypes().contains(command.getClass())) {
-                log.error("Unexpected command received");
-                continue;
-            }
-            log.debug("Command received: " + command);
-            if (!(command instanceof AbstractCommand)) {
-                log.warn("Incorrect command received: " + command);
-                continue;
-            }
-            final Serializable response = onCommand((AbstractCommand) command);
-            log.debug(format("Response for %s is: %s", command, response));
-            writeBytes(SerializationUtils.serialize(response), getSeparator());
         }
     }
 
@@ -85,11 +90,12 @@ public class CommandClientListener extends AbstractClientListener implements Abs
 
     /**
      * Sends command to opposite side
+     *
      * @param command command to be sent
-     * @param <T> generic type
+     * @param <T>     generic type
      */
-    public <T extends AbstractCommand> void send(T command) {
-        log.debug("Start to send command: " + command);
+    public <T extends AbstractCommand> void send(T command) throws IOException {
+        log.debug("Start to send command: {}", command);
         writeBytes(SerializationUtils.serialize(command), getSeparator());
     }
 

src/main/java/me/bvn13/sewy/CommandServer.java

@@ -16,19 +16,12 @@
 package me.bvn13.sewy;
 
 import me.bvn13.sewy.command.AbstractCommand;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 import java.io.IOException;
 import java.net.InetAddress;
 import java.net.ServerSocket;
 import java.net.Socket;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.Iterator;
-import java.util.List;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
+import java.util.function.Consumer;
 import java.util.function.Function;
 
 import static java.lang.String.format;
@@ -50,8 +43,8 @@ public class CommandServer extends Server<CommandClientListener> {
     }
 
     /**
-     * @param host host to bind in order to start listen to clients
-     * @param port port to start listen to
+     * @param host                host to bind in order to start listen to clients
+     * @param port                port to start listen to
      * @param clientListenerClass client listen class to be used for communication
      */
     public CommandServer(String host, int port, Class clientListenerClass) {
@@ -59,9 +52,8 @@ public class CommandServer extends Server<CommandClientListener> {
     }
 
     /**
-     *
-     * @param host host to bind in order to start listen to clients
-     * @param port port to start listen to
+     * @param host                      host to bind in order to start listen to clients
+     * @param port                      port to start listen to
      * @param clientListenerConstructor to provide constructor for client listener (see {@link CommandServer#CommandServer(String, int, Class)})
      */
     @SuppressWarnings("unchecked")
@@ -73,10 +65,12 @@ public class CommandServer extends Server<CommandClientListener> {
                 socket = server;
 
                 while (!server.isClosed()) {
-                    final Socket client = server.accept();
-                    final CommandClientListener clientListener = clientListenerConstructor.apply(client);
-                    executor.execute(clientListener);
-                    clients.add(clientListener);
+                    if (!isMaximumClientsAchieved()) {
+                        final Socket client = server.accept();
+                        final CommandClientListener clientListener = clientListenerConstructor.apply(client);
+                        executor.execute(clientListener);
+                        clients.add(clientListener);
+                    }
                 }
 
             } catch (IOException e) {
@@ -87,14 +81,31 @@ public class CommandServer extends Server<CommandClientListener> {
 
     /**
      * Sends command to every client
-     * @param command command to be sent
-     * @param <T> generic type
+     *
+     * @param command     command to be sent
+     * @param <T>         generic type
      */
     public <T extends AbstractCommand> void send(T command) {
-        log.debug("Start to send command: " + command);
-        for (CommandClientListener client : clients) {
-            client.send(command);
-        }
+        send(command, client -> {});
     }
 
+    /**
+     * Sends command to every client
+     *
+     * @param command     command to be sent
+     * @param <T>         generic type
+     * @param onException for catching errors while sending. Do not throw any Exception inside onException callback -
+     *                    it leads to stopping sending the command to remaining clients
+     */
+    public <T extends AbstractCommand> void send(T command, Consumer<CommandClientListener> onException) {
+        log.debug("Start to send command: " + command);
+        for (CommandClientListener client : clients) {
+            try {
+                client.send(command);
+            } catch (IOException e) {
+                log.error("Failed to send command " + command, e);
+                onException.accept(client);
+            }
+        }
+    }
 }

src/main/java/me/bvn13/sewy/Server.java

@@ -46,12 +46,14 @@ public class Server<T extends AbstractClientListener> {
 
     protected ServerSocket socket;
 
+    private int maxClientsCount;
+
     protected Server() {
     }
 
     /**
-     * @param host host to bind in order to start listen to clients
-     * @param port port to start listen to
+     * @param host                host to bind in order to start listen to clients
+     * @param port                port to start listen to
      * @param clientListenerClass client listen class to be used for communication
      */
     public Server(String host, int port, Class clientListenerClass) {
@@ -59,9 +61,8 @@ public class Server<T extends AbstractClientListener> {
     }
 
     /**
-     *
-     * @param host host to bind in order to start listen to clients
-     * @param port port to start listen to
+     * @param host                      host to bind in order to start listen to clients
+     * @param port                      port to start listen to
      * @param clientListenerConstructor to provide constructor for client listener (see {@link me.bvn13.sewy.Server#Server(java.lang.String, int, java.lang.Class)})
      */
     @SuppressWarnings("unchecked")
@@ -73,17 +74,19 @@ public class Server<T extends AbstractClientListener> {
                 socket = server;
 
                 while (!server.isClosed()) {
-                    final Socket client = server.accept();
-                    final T clientListener = clientListenerConstructor.apply(client);
-                    executor.execute(clientListener);
-                    clients.add(clientListener);
+                    if (!isMaximumClientsAchieved()) {
+                        final Socket client = server.accept();
+                        final T clientListener = clientListenerConstructor.apply(client);
+                        executor.execute(clientListener);
+                        clients.add(clientListener);
+                    }
+                    Thread.yield();
                 }
 
             } catch (IOException e) {
                 log.error(format("Error while conversation with %s:%d", host, port), e);
             }
         });
-
     }
 
     /**
@@ -98,15 +101,45 @@ public class Server<T extends AbstractClientListener> {
             client.stop();
             iterator.remove();
         }
+        try {
+            if (socket != null) {
+                socket.close();
+            }
+        } catch (IOException e) {
+            log.error("Failed to close socket");
+        }
         executor.shutdown();
     }
 
     /**
      * To check whether the server is ready for new connections
+     *
      * @return
      */
     public boolean isListening() {
         return socket != null && socket.isBound();
     }
 
+    /**
+     * Returns count of connected clients
+     *
+     * @return count of connected clients
+     */
+    public int getClientsCount() {
+        return clients.size();
+    }
+
+    /**
+     * Sets maximum clients to be connected to server
+     *
+     * @param count maximum clients count
+     */
+    public void setMaxClientsCount(int count) {
+        maxClientsCount = count;
+    }
+
+    protected boolean isMaximumClientsAchieved() {
+        return maxClientsCount == 0
+                || clients.size() >= maxClientsCount;
+    }
 }

src/main/java/me/bvn13/sewy/Sewy.java

@@ -33,7 +33,7 @@ public final class Sewy {
     private static final ReentrantLock LOCK = new ReentrantLock();
 
     private final List<Class<?>> registeredDataTypes = new CopyOnWriteArrayList<>();
-    private byte separator = SEPARATOR;
+    private byte[] separator = new byte[] { SEPARATOR };
 
     /**
      * Registers command in white list for further communications
@@ -55,11 +55,11 @@ public final class Sewy {
         }
     }
 
-    public static byte getSeparator() {
+    public static byte[] getSeparator() {
         return getInstance().separator;
     }
 
-    public static void setSeparator(byte separator) {
+    public static void setSeparator(byte[] separator) {
         try {
             LOCK.lock();
             getInstance().separator = separator;

src/test/java/me/bvn13/sewy/EchoClientListener.java

@@ -15,6 +15,9 @@
  */
 package me.bvn13.sewy;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import java.net.Socket;
 
 /**
@@ -22,6 +25,9 @@ import java.net.Socket;
  * Writes into socket all the data received before
  */
 public class EchoClientListener extends AbstractClientListener {
+
+    private final Logger log = LoggerFactory.getLogger(EchoClientListener.class);
+
     public EchoClientListener(Socket socket) {
         super(socket);
     }
@@ -33,8 +39,12 @@ public class EchoClientListener extends AbstractClientListener {
     public void run() {
         while (socket.isConnected()) {
             Thread.yield();
-            final String data = readLine();
-            writeLine(data);
+            try {
+                final String data = readLine();
+                writeLine(data);
+            } catch (Exception e) {
+                log.error("", e);
+            }
         }
     }
 }

src/test/java/me/bvn13/sewy/ServerTest.java

@@ -16,6 +16,7 @@
 package me.bvn13.sewy;
 
 import me.bvn13.sewy.command.AbstractCommand;
+import me.bvn13.sewy.command.ComplexCommand;
 import me.bvn13.sewy.command.PingCommand;
 import me.bvn13.sewy.command.PongCommand;
 import org.junit.jupiter.api.Assertions;
@@ -23,6 +24,7 @@ import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.ValueSource;
 
 import java.util.concurrent.atomic.AtomicLong;
+import java.util.concurrent.atomic.AtomicReference;
 
 public class ServerTest {
 
@@ -81,7 +83,7 @@ public class ServerTest {
 
     @ParameterizedTest
     @ValueSource(ints = START_PORT + 6)
-    void serverIsAbleToPingPong(int port) throws InterruptedException {
+    void serverIsAbleToPingPong(int port) throws Exception {
         Sewy.register(PingCommand.class);
         Sewy.register(PongCommand.class);
 
@@ -112,4 +114,43 @@ public class ServerTest {
         Assertions.assertTrue(latency.get() > 0);
     }
 
+    @ParameterizedTest
+    @ValueSource(ints = START_PORT + 7)
+    void wideSeparatorTest(int port) throws Exception {
+        Sewy.register(ComplexCommand.class);
+        Sewy.setSeparator(new byte[] { '\n', 'e', 'n', 'd', '\n' });
+
+        AtomicReference<ComplexCommand> check = new AtomicReference<>();
+
+        CommandServer server = new CommandServer("localhost", port, (socket) -> new CommandClientListener(socket) {
+            @Override
+            public AbstractCommand onCommand(AbstractCommand command) {
+                if (command instanceof ComplexCommand) {
+                    check.set((ComplexCommand) command);
+                    return null;
+                }
+                throw new IllegalArgumentException(command.toString());
+            }
+        });
+
+        CommandClient client = new CommandClient("localhost", port, (socket) -> new CommandClientListener(socket) {
+            @Override
+            public AbstractCommand onCommand(AbstractCommand command) {
+                throw new IllegalArgumentException(command.toString());
+            }
+        });
+
+        ComplexCommand command = new ComplexCommand();
+        command.add(new ComplexCommand.SimpleData("a1"));
+        command.add(new ComplexCommand.SimpleData("b2"));
+        command.add(new ComplexCommand.SimpleData("finish"));
+
+        client.send(command);
+        Thread.sleep(1000);
+        Assertions.assertNotNull(check.get());
+        Assertions.assertEquals(3, check.get().getDatum().size());
+        Assertions.assertEquals("a1", check.get().getDatum().get(0).getString());
+        Assertions.assertEquals("b2", check.get().getDatum().get(1).getString());
+        Assertions.assertEquals("finish", check.get().getDatum().get(2).getString());
+    }
 }

src/test/java/me/bvn13/sewy/command/ComplexCommand.java

@@ -0,0 +1,44 @@
+package me.bvn13.sewy.command;
+
+import java.io.Serializable;
+import java.util.ArrayList;
+import java.util.List;
+
+public class ComplexCommand extends AbstractCommand {
+
+    private List<SimpleData> datum;
+
+    public ComplexCommand() {
+        datum = new ArrayList<>();
+    }
+
+    public ComplexCommand(List<SimpleData> datum) {
+        this.datum = datum;
+    }
+
+    public void add(SimpleData data) {
+        datum.add(data);
+    }
+
+    public ComplexCommand setDatum(List<SimpleData> datum) {
+        this.datum = datum;
+        return this;
+    }
+
+    public List<SimpleData> getDatum() {
+        return datum;
+    }
+
+    public static class SimpleData implements Serializable {
+        private final String string;
+
+        public SimpleData(String string) {
+            this.string = string;
+        }
+
+        public String getString() {
+            return string;
+        }
+    }
+
+}