Simple ftp

.travis.yml

@@ -3,4 +3,8 @@ language: java
 sudo: false
 
 notifications:
-  email: false
+  email: false
+
+env:
+  - TEST_DIR=SimpleFTP
+script: cd $TEST_DIR && ./gradlew clean check

SimpleFTP/FTPClient/build.gradle

@@ -0,0 +1,14 @@
+group 'ru.spbau.dkaznacheev'
+version '1.0-SNAPSHOT'
+
+apply plugin: 'java'
+
+sourceCompatibility = 1.8
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    testCompile group: 'junit', name: 'junit', version: '4.12'
+}

SimpleFTP/FTPClient/src/main/java/ru/spbau/dkaznacheev/simpleftp/Client.java

@@ -0,0 +1,89 @@
+package ru.spbau.dkaznacheev.simpleftp;
+
+import java.io.*;
+import java.net.ConnectException;
+import java.net.Socket;
+import java.net.UnknownHostException;
+import java.util.Scanner;
+
+public class Client {
+
+    /**
+     * Downloads a file from sever
+     * @param in inputstream of a socket
+     * @param name name of the file
+     */
+    private static void receiveFile(DataInputStream in, String name) throws IOException{
+        long length = in.readLong();
+        if (length == 0) {
+            System.out.println("No such file");
+            return;
+        }
+        try (FileOutputStream out = new FileOutputStream(simpleName(name))) {
+            byte[] buffer = new byte[4096];
+            long remaining = length;
+            int read;
+            while ((read = in.read(buffer, 0, (int) Math.min(buffer.length, remaining))) > 0) {
+                remaining -= read;
+                out.write(buffer);
+            }
+        }
+    }
+
+    /**
+     * Returns simple file name of the filepath.
+     * @param path path to file
+     * @return filename
+     */
+    private static String simpleName(String path) {
+        return new File(path).getName();
+    }
+
+    public static void main(String[] args) {
+        try (
+                Socket socket = new Socket("127.0.0.1", 8080);
+                PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
+                DataInputStream in = new DataInputStream(socket.getInputStream());
+                Scanner stdIn = new Scanner(System.in)
+        ) {
+            ResponseCode fromServer;
+            String fromUser;
+            boolean exit = false;
+            while (!exit) {
+                fromUser = stdIn.nextLine();
+                if (fromUser != null) {
+                    out.println(fromUser);
+                }
+                fromServer = ResponseCode.values()[in.readInt()];
+                switch (fromServer) {
+                    case CLOSE_CONNECTION: {
+                        exit = true;
+                        break;
+                    }
+                    case INVALID_COMMAND: {
+                        System.out.println("Invalid command");
+                        break;
+                    }
+                    case FOLDER_DESCRIPTION: {
+                        FolderDescription description = FolderDescription.read(in);
+                        description.print();
+                        break;
+                    }
+                    case FILE_SEND: {
+                        String[] parts = fromUser.split(" ");
+                        receiveFile(in, parts[1]);
+                        break;
+                    }
+                }
+            }
+
+        } catch (UnknownHostException e) {
+            System.err.println("Unknown host");
+        } catch (ConnectException e) {
+            System.err.println("Connection refused");
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+    }
+}
+

SimpleFTP/FTPServer/build.gradle

@@ -0,0 +1,14 @@
+group 'ru.spbau.dkaznacheev'
+version '1.0-SNAPSHOT'
+
+apply plugin: 'java'
+
+sourceCompatibility = 1.8
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    testCompile group: 'junit', name: 'junit', version: '4.12'
+}

SimpleFTP/FTPServer/src/main/java/ru/spbau/dkaznacheev/simpleftp/Server.java

@@ -0,0 +1,111 @@
+package ru.spbau.dkaznacheev.simpleftp;
+
+import java.io.*;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.net.SocketException;
+
+import static ru.spbau.dkaznacheev.simpleftp.ResponseCode.*;
+
+/**
+ * Simple FTP server that can handle multiple clients and send files over sockets.
+ */
+public class Server {
+
+    /**
+     * Sends file over ServerSocket's DataOutputStream.
+     * @param name filename
+     * @param out output stream
+     */
+    private static void sendFile(String name, DataOutputStream out) throws IOException{
+        File file = new File(name);
+        if (!file.exists()) {
+            out.writeLong(0);
+            return;
+        }
+        out.writeLong(file.length());
+        byte[] buffer = new byte[4096];
+        int read;
+        try (FileInputStream in = new FileInputStream(file)) {
+            while ((read = in.read(buffer)) > -1) {
+                out.write(buffer, 0, read);
+            }
+        }
+
+    }
+
+    /**
+     * Client handler, runs in a separate thread as long as there is a connectin with  a client.
+     */
+    private static class FTPThread extends Thread {
+
+        /**
+         * Socket f server-client connection
+         */
+        private Socket socket;
+
+        public FTPThread(Socket socket) {
+            this.socket = socket;
+        }
+
+        @Override
+        public void run() {
+            try (
+                DataOutputStream out = new DataOutputStream(socket.getOutputStream());
+                BufferedReader in = new BufferedReader(
+                    new InputStreamReader(socket.getInputStream()))
+            ) {
+                String inputLine;
+                while ((inputLine = in.readLine()) != null) {
+                    if (inputLine.equals("0")) {
+                        out.writeInt(CLOSE_CONNECTION.ordinal());
+                        break;
+                    }
+
+                    String[] parts = inputLine.split(" ");
+                    if (parts.length != 2) {
+                        out.writeInt(INVALID_COMMAND.ordinal());
+                        continue;
+                    }
+                    String command = parts[0];
+                    String path = parts[1];
+
+                    if (command.equals("1")) {
+                        FolderDescription description = FolderDescription.describeFolder(path);
+                        out.writeInt(FOLDER_DESCRIPTION.ordinal());
+                        description.write(out);
+                    } else if (command.equals("2")) {
+                        out.writeInt(FILE_SEND.ordinal());
+                        sendFile(path, out);
+                    } else {
+                        out.writeInt(INVALID_COMMAND.ordinal());
+                    }
+                }
+                socket.close();
+            } catch (SocketException e) {
+                System.out.println("Goodbye");
+            }
+            catch (IOException e) {
+                System.err.println("IOException on thread " + Thread.currentThread().getName());
+            }
+        }
+    }
+
+    public static void main(String[] args) {
+        ServerSocket serverSocket;
+        try {
+            serverSocket = new ServerSocket(8080);
+        } catch (IOException e) {
+            System.err.println("Error creating server");
+            return;
+        }
+        while (true) {
+            try {
+                Socket clientSocket = serverSocket.accept();
+                new FTPThread(clientSocket).start();
+            } catch (IOException e) {
+                System.err.println("Exception on client connecting");
+            }
+        }
+    }
+}

SimpleFTP/build.gradle

@@ -0,0 +1,14 @@
+group 'ru.spbau.dkaznacheev.simpleftp'
+version '1.0-SNAPSHOT'
+
+apply plugin: 'java'
+
+sourceCompatibility = 1.8
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    testCompile group: 'junit', name: 'junit', version: '4.12'
+}

SimpleFTP/gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,6 @@
+#Wed May 30 23:52:07 MSK 2018
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-3.5-rc-2-bin.zip