diff --git a/.travis.yml b/.travis.yml
index aac6a7a..b9018d1 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,4 +3,8 @@ language: java
 sudo: false
 
 notifications:
-  email: false
\ No newline at end of file
+  email: false
+
+env:
+  - TEST_DIR=SimpleFTP
+script: cd $TEST_DIR && ./gradlew clean check
\ No newline at end of file
diff --git a/SimpleFTP/FTPClient/build.gradle b/SimpleFTP/FTPClient/build.gradle
new file mode 100644
index 0000000..c73fa91
--- /dev/null
+++ b/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'
+}
diff --git a/SimpleFTP/FTPClient/src/main/java/ru/spbau/dkaznacheev/simpleftp/Client.java b/SimpleFTP/FTPClient/src/main/java/ru/spbau/dkaznacheev/simpleftp/Client.java
new file mode 100644
index 0000000..77cb2ed
--- /dev/null
+++ b/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();
+        }
+    }
+}
+
diff --git a/SimpleFTP/FTPServer/build.gradle b/SimpleFTP/FTPServer/build.gradle
new file mode 100644
index 0000000..c73fa91
--- /dev/null
+++ b/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'
+}
diff --git a/SimpleFTP/FTPServer/src/main/java/ru/spbau/dkaznacheev/simpleftp/Server.java b/SimpleFTP/FTPServer/src/main/java/ru/spbau/dkaznacheev/simpleftp/Server.java
new file mode 100644
index 0000000..d184aa8
--- /dev/null
+++ b/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");
+            }
+        }
+    }
+}
diff --git a/SimpleFTP/build.gradle b/SimpleFTP/build.gradle
new file mode 100644
index 0000000..fc18ffe
--- /dev/null
+++ b/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'
+}
diff --git a/SimpleFTP/gradle/wrapper/gradle-wrapper.jar b/SimpleFTP/gradle/wrapper/gradle-wrapper.jar
new file mode 100644
index 0000000..048d015
Binary files /dev/null and b/SimpleFTP/gradle/wrapper/gradle-wrapper.jar differ
diff --git a/SimpleFTP/gradle/wrapper/gradle-wrapper.properties b/SimpleFTP/gradle/wrapper/gradle-wrapper.properties
new file mode 100644
index 0000000..33b8486
--- /dev/null
+++ b/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
diff --git a/SimpleFTP/gradlew b/SimpleFTP/gradlew
new file mode 100755
index 0000000..4453cce
--- /dev/null
+++ b/SimpleFTP/gradlew
@@ -0,0 +1,172 @@
+#!/usr/bin/env sh
+
+##############################################################################
+##
+##  Gradle start up script for UN*X
+##
+##############################################################################
+
+# Attempt to set APP_HOME
+# Resolve links: $0 may be a link
+PRG="$0"
+# Need this for relative symlinks.
+while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+        PRG="$link"
+    else
+        PRG=`dirname "$PRG"`"/$link"
+    fi
+done
+SAVED="`pwd`"
+cd "`dirname \"$PRG\"`/" >/dev/null
+APP_HOME="`pwd -P`"
+cd "$SAVED" >/dev/null
+
+APP_NAME="Gradle"
+APP_BASE_NAME=`basename "$0"`
+
+# Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+DEFAULT_JVM_OPTS=""
+
+# Use the maximum available, or set MAX_FD != -1 to use that value.
+MAX_FD="maximum"
+
+warn ( ) {
+    echo "$*"
+}
+
+die ( ) {
+    echo
+    echo "$*"
+    echo
+    exit 1
+}
+
+# OS specific support (must be 'true' or 'false').
+cygwin=false
+msys=false
+darwin=false
+nonstop=false
+case "`uname`" in
+  CYGWIN* )
+    cygwin=true
+    ;;
+  Darwin* )
+    darwin=true
+    ;;
+  MINGW* )
+    msys=true
+    ;;
+  NONSTOP* )
+    nonstop=true
+    ;;
+esac
+
+CLASSPATH=$APP_HOME/gradle/wrapper/gradle-wrapper.jar
+
+# Determine the Java command to use to start the JVM.
+if [ -n "$JAVA_HOME" ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+        # IBM's JDK on AIX uses strange locations for the executables
+        JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+        JAVACMD="$JAVA_HOME/bin/java"
+    fi
+    if [ ! -x "$JAVACMD" ] ; then
+        die "ERROR: JAVA_HOME is set to an invalid directory: $JAVA_HOME
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+    fi
+else
+    JAVACMD="java"
+    which java >/dev/null 2>&1 || die "ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+
+Please set the JAVA_HOME variable in your environment to match the
+location of your Java installation."
+fi
+
+# Increase the maximum file descriptors if we can.
+if [ "$cygwin" = "false" -a "$darwin" = "false" -a "$nonstop" = "false" ] ; then
+    MAX_FD_LIMIT=`ulimit -H -n`
+    if [ $? -eq 0 ] ; then
+        if [ "$MAX_FD" = "maximum" -o "$MAX_FD" = "max" ] ; then
+            MAX_FD="$MAX_FD_LIMIT"
+        fi
+        ulimit -n $MAX_FD
+        if [ $? -ne 0 ] ; then
+            warn "Could not set maximum file descriptor limit: $MAX_FD"
+        fi
+    else
+        warn "Could not query maximum file descriptor limit: $MAX_FD_LIMIT"
+    fi
+fi
+
+# For Darwin, add options to specify how the application appears in the dock
+if $darwin; then
+    GRADLE_OPTS="$GRADLE_OPTS \"-Xdock:name=$APP_NAME\" \"-Xdock:icon=$APP_HOME/media/gradle.icns\""
+fi
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin ; then
+    APP_HOME=`cygpath --path --mixed "$APP_HOME"`
+    CLASSPATH=`cygpath --path --mixed "$CLASSPATH"`
+    JAVACMD=`cygpath --unix "$JAVACMD"`
+
+    # We build the pattern for arguments to be converted via cygpath
+    ROOTDIRSRAW=`find -L / -maxdepth 1 -mindepth 1 -type d 2>/dev/null`
+    SEP=""
+    for dir in $ROOTDIRSRAW ; do
+        ROOTDIRS="$ROOTDIRS$SEP$dir"
+        SEP="|"
+    done
+    OURCYGPATTERN="(^($ROOTDIRS))"
+    # Add a user-defined pattern to the cygpath arguments
+    if [ "$GRADLE_CYGPATTERN" != "" ] ; then
+        OURCYGPATTERN="$OURCYGPATTERN|($GRADLE_CYGPATTERN)"
+    fi
+    # Now convert the arguments - kludge to limit ourselves to /bin/sh
+    i=0
+    for arg in "$@" ; do
+        CHECK=`echo "$arg"|egrep -c "$OURCYGPATTERN" -`
+        CHECK2=`echo "$arg"|egrep -c "^-"`                                 ### Determine if an option
+
+        if [ $CHECK -ne 0 ] && [ $CHECK2 -eq 0 ] ; then                    ### Added a condition
+            eval `echo args$i`=`cygpath --path --ignore --mixed "$arg"`
+        else
+            eval `echo args$i`="\"$arg\""
+        fi
+        i=$((i+1))
+    done
+    case $i in
+        (0) set -- ;;
+        (1) set -- "$args0" ;;
+        (2) set -- "$args0" "$args1" ;;
+        (3) set -- "$args0" "$args1" "$args2" ;;
+        (4) set -- "$args0" "$args1" "$args2" "$args3" ;;
+        (5) set -- "$args0" "$args1" "$args2" "$args3" "$args4" ;;
+        (6) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" ;;
+        (7) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" ;;
+        (8) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" ;;
+        (9) set -- "$args0" "$args1" "$args2" "$args3" "$args4" "$args5" "$args6" "$args7" "$args8" ;;
+    esac
+fi
+
+# Escape application args
+save ( ) {
+    for i do printf %s\\n "$i" | sed "s/'/'\\\\''/g;1s/^/'/;\$s/\$/' \\\\/" ; done
+    echo " "
+}
+APP_ARGS=$(save "$@")
+
+# Collect all arguments for the java command, following the shell quoting and substitution rules
+eval set -- $DEFAULT_JVM_OPTS $JAVA_OPTS $GRADLE_OPTS "\"-Dorg.gradle.appname=$APP_BASE_NAME\"" -classpath "\"$CLASSPATH\"" org.gradle.wrapper.GradleWrapperMain "$APP_ARGS"
+
+# by default we should be in the correct project dir, but when run from Finder on Mac, the cwd is wrong
+if [ "$(uname)" = "Darwin" ] && [ "$HOME" = "$PWD" ]; then
+  cd "$(dirname "$0")"
+fi
+
+exec "$JAVACMD" "$@"
diff --git a/SimpleFTP/gradlew.bat b/SimpleFTP/gradlew.bat
new file mode 100644
index 0000000..e95643d
--- /dev/null
+++ b/SimpleFTP/gradlew.bat
@@ -0,0 +1,84 @@
+@if "%DEBUG%" == "" @echo off
+@rem ##########################################################################
+@rem
+@rem  Gradle startup script for Windows
+@rem
+@rem ##########################################################################
+
+@rem Set local scope for the variables with windows NT shell
+if "%OS%"=="Windows_NT" setlocal
+
+set DIRNAME=%~dp0
+if "%DIRNAME%" == "" set DIRNAME=.
+set APP_BASE_NAME=%~n0
+set APP_HOME=%DIRNAME%
+
+@rem Add default JVM options here. You can also use JAVA_OPTS and GRADLE_OPTS to pass JVM options to this script.
+set DEFAULT_JVM_OPTS=
+
+@rem Find java.exe
+if defined JAVA_HOME goto findJavaFromJavaHome
+
+set JAVA_EXE=java.exe
+%JAVA_EXE% -version >NUL 2>&1
+if "%ERRORLEVEL%" == "0" goto init
+
+echo.
+echo ERROR: JAVA_HOME is not set and no 'java' command could be found in your PATH.
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:findJavaFromJavaHome
+set JAVA_HOME=%JAVA_HOME:"=%
+set JAVA_EXE=%JAVA_HOME%/bin/java.exe
+
+if exist "%JAVA_EXE%" goto init
+
+echo.
+echo ERROR: JAVA_HOME is set to an invalid directory: %JAVA_HOME%
+echo.
+echo Please set the JAVA_HOME variable in your environment to match the
+echo location of your Java installation.
+
+goto fail
+
+:init
+@rem Get command-line arguments, handling Windows variants
+
+if not "%OS%" == "Windows_NT" goto win9xME_args
+
+:win9xME_args
+@rem Slurp the command line arguments.
+set CMD_LINE_ARGS=
+set _SKIP=2
+
+:win9xME_args_slurp
+if "x%~1" == "x" goto execute
+
+set CMD_LINE_ARGS=%*
+
+:execute
+@rem Setup the command line
+
+set CLASSPATH=%APP_HOME%\gradle\wrapper\gradle-wrapper.jar
+
+@rem Execute Gradle
+"%JAVA_EXE%" %DEFAULT_JVM_OPTS% %JAVA_OPTS% %GRADLE_OPTS% "-Dorg.gradle.appname=%APP_BASE_NAME%" -classpath "%CLASSPATH%" org.gradle.wrapper.GradleWrapperMain %CMD_LINE_ARGS%
+
+:end
+@rem End local scope for the variables with windows NT shell
+if "%ERRORLEVEL%"=="0" goto mainEnd
+
+:fail
+rem Set variable GRADLE_EXIT_CONSOLE if you need the _script_ return code instead of
+rem the _cmd.exe /c_ return code!
+if  not "" == "%GRADLE_EXIT_CONSOLE%" exit 1
+exit /b 1
+
+:mainEnd
+if "%OS%"=="Windows_NT" endlocal
+
+:omega
diff --git a/SimpleFTP/settings.gradle b/SimpleFTP/settings.gradle
new file mode 100644
index 0000000..84ede45
--- /dev/null
+++ b/SimpleFTP/settings.gradle
@@ -0,0 +1,2 @@
+rootProject.name = 'SimpleFTP'
+
diff --git a/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/Client.java b/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/Client.java
new file mode 100644
index 0000000..67d5ff1
--- /dev/null
+++ b/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/Client.java
@@ -0,0 +1,154 @@
+package ru.spbau.dkaznacheev.simpleftp;
+
+import java.io.*;
+import java.net.Socket;
+import java.util.Scanner;
+
+/**
+ * Client class for SimpleFTP. It can print folder descriptions and download files.
+ */
+public class Client {
+    /**
+     * Code for sending folder description request.
+     */
+    private static final int FOLDER_CODE = 1;
+
+    /**
+     * Code for sending file download request.
+     */
+    private static final int FILE_CODE = 2;
+
+    /**
+     * Client's input stream.
+     */
+    private final DataInputStream in;
+
+    /**
+     * Client's output stream.
+     */
+    private final DataOutputStream out;
+
+    public Client(Socket socket) throws IOException {
+        in = new DataInputStream(socket.getInputStream());
+        out = new DataOutputStream(socket.getOutputStream());//PrintWriter(socket.getOutputStream());
+    }
+
+    /**
+     * Sends a query to describe folder and recieves a FolderDescription.
+     * @param path path to folder
+     * @return FolderDescription of a folder
+     */
+    public FolderDescription describeFolderQuery(String path) throws QueryFormatException, IOException {
+        out.writeInt(FOLDER_CODE);
+        out.writeUTF(path);
+        ResponseCode fromServer = ResponseCode.values()[in.readInt()];
+        switch (fromServer) {
+            case INVALID_COMMAND: {
+                throw new QueryFormatException();
+            }
+            case FOLDER_DESCRIPTION: {
+                return read();
+            }
+            default: {
+                return null;
+            }
+        }
+    }
+
+    /**
+     * Sends a query to download file and downloads it.
+     * @param filename path to file
+     */
+    public void getFileQuery(String filename) throws IOException, QueryFormatException {
+        out.writeInt(FILE_CODE);
+        out.writeUTF(filename);
+        ResponseCode fromServer = ResponseCode.values()[in.readInt()];
+        switch (fromServer) {
+            case INVALID_COMMAND: {
+                throw new QueryFormatException();
+            }
+            case FILE_SEND: {
+                receiveFile(filename);
+                break;
+            }
+        }
+    }
+
+    /**
+     * Reads FolderDescription from InputStream.
+     * @return read FolderDescription
+     */
+    private FolderDescription read() throws IOException {
+        int size = in.readInt();
+        if (size == 0) {
+            return new FolderDescription(0, null);
+        }
+        FolderDescription.FileDescription[] files = new FolderDescription.FileDescription[size];
+
+        for (int i = 0; i < size; i++)  {
+            String name = in.readUTF();
+            boolean isDir = in.readBoolean();
+            files[i] = new FolderDescription.FileDescription(name, isDir);
+        }
+        return new FolderDescription(size, files);
+    }
+
+    /**
+     * 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();
+    }
+
+    /**
+     * Downloads a file from server.
+     * @param name name of the file
+     */
+    private void receiveFile(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);
+            }
+        }
+    }
+
+    /**
+     * Console interface for client.
+     */
+    public static void main(String[] args) {
+
+        try (Socket socket = new Socket("127.0.0.1", 8080);
+            Scanner stdIn = new Scanner(System.in)) {
+            String query;
+            Client client = new Client(socket);
+            while ((query = stdIn.nextLine()) != null) {
+                String[] queryParts = query.split(" ");
+                if (queryParts.length == 2) {
+                    if (queryParts[0].equals("1")) {
+                        client.describeFolderQuery(queryParts[1]).print();
+                    } else if (queryParts[0].equals("2")) {
+                        client.getFileQuery(queryParts[1]);
+                        System.out.println("Downloaded" + simpleName(queryParts[1]));
+                    } else {
+                        System.out.println("Incorrect command!");
+                    }
+                } else {
+                    System.out.println("Incorrect input!");
+                }
+            }
+        }  catch (IOException | QueryFormatException e) {
+            e.printStackTrace();
+        }
+    }
+}
diff --git a/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/FolderDescription.java b/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/FolderDescription.java
new file mode 100644
index 0000000..ce306c2
--- /dev/null
+++ b/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/FolderDescription.java
@@ -0,0 +1,107 @@
+package ru.spbau.dkaznacheev.simpleftp;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.File;
+import java.io.IOException;
+
+/**
+ * Class describing folder contents.
+ */
+public class FolderDescription {
+
+    /**
+     * Size of the folder.
+     */
+    private final int size;
+
+    /**
+     * Description of folder's contents.
+     */
+    private final FileDescription[] files;
+
+    public FolderDescription(int size, FileDescription[] files) {
+        this.size = size;
+        this.files = files;
+    }
+
+    public int getSize() {
+        return size;
+    }
+
+    public FileDescription[] getFiles() {
+        return files;
+    }
+
+    /**
+     * Prints FolderDescription to console.
+     */
+    public void print() {
+        if (size == 0) {
+            System.out.println("Folder not found");
+            return;
+        }
+        System.out.println(size + " files:");
+        for (FileDescription description : files) {
+            System.out.print(description.name);
+            if (description.isDir) {
+                System.out.print(": folder");
+            }
+            System.out.println();
+        }
+        System.out.println();
+    }
+
+    /**
+     * Returns a FolderDescription from path to folder.
+     * If it is the path of non-folder file, returns a FolderDescription with size = 0.
+     * @param path path to file/folder
+     * @return FolderDescription on this path
+     */
+    public static FolderDescription describeFolder(String path) {
+        File root = new File(path);
+
+        File[] contents = root.listFiles();
+        if (contents == null) {
+            return new FolderDescription(0, null);
+        }
+
+        FileDescription[] files = new FileDescription[contents.length];
+        int size = contents.length;
+        for (int i = 0; i < size; i++) {
+            String name = contents[i].getName();
+            boolean isDir = contents[i].isDirectory();
+            files[i] = new FileDescription(name, isDir);
+        }
+        return new FolderDescription(size, files);
+    }
+
+    /**
+     * Class describing one file.
+     */
+    public static class FileDescription {
+
+        /**
+         * Filename.
+         */
+        private final String name;
+
+        /**
+         * Whether a file is a directory or not.
+         */
+        private final boolean isDir;
+
+        public String getName() {
+            return name;
+        }
+
+        public boolean isDir() {
+            return isDir;
+        }
+
+        public FileDescription(String name, boolean isDir) {
+            this.name = name;
+            this.isDir = isDir;
+        }
+    }
+}
diff --git a/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/QueryFormatException.java b/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/QueryFormatException.java
new file mode 100644
index 0000000..4dafcdc
--- /dev/null
+++ b/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/QueryFormatException.java
@@ -0,0 +1,4 @@
+package ru.spbau.dkaznacheev.simpleftp;
+
+public class QueryFormatException extends Throwable {
+}
diff --git a/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/ResponseCode.java b/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/ResponseCode.java
new file mode 100644
index 0000000..efa2088
--- /dev/null
+++ b/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/ResponseCode.java
@@ -0,0 +1,31 @@
+package ru.spbau.dkaznacheev.simpleftp;
+
+/**
+ * Codes that client and server use to send util information.
+ */
+public enum ResponseCode {
+    /**
+     * If a connection is closed.
+     */
+    CLOSE_CONNECTION,
+
+    /**
+     * If a connection is opened.
+     */
+    OPEN_CONNECTION,
+
+    /**
+     * If a client sent an invalid command.
+     */
+    INVALID_COMMAND,
+
+    /**
+     * If a server is going to send a FolderDescription.
+     */
+    FOLDER_DESCRIPTION,
+
+    /**
+     * If a server is going to send a file.
+     */
+    FILE_SEND
+}
\ No newline at end of file
diff --git a/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/Server.java b/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/Server.java
new file mode 100644
index 0000000..0b85465
--- /dev/null
+++ b/SimpleFTP/src/main/java/ru/spbau/dkaznacheev/simpleftp/Server.java
@@ -0,0 +1,186 @@
+package ru.spbau.dkaznacheev.simpleftp;
+
+import java.io.*;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.util.concurrent.*;
+
+import static ru.spbau.dkaznacheev.simpleftp.ResponseCode.*;
+import static ru.spbau.dkaznacheev.simpleftp.ResponseCode.INVALID_COMMAND;
+
+/**
+ * Server class for SimpleFTP. It can send files and folder descriptions.
+ */
+public class Server {
+
+    /**
+     * Number of threads to run thread pool on.
+     */
+    private static final int THREADS = 4;
+
+    /**
+     * A thread pool for describing folders.
+     */
+    private final ExecutorService folderDescriber = Executors.newFixedThreadPool(THREADS);
+
+    /**
+     * Server's ServerSocket.
+     */
+    private ServerSocket serverSocket;
+
+    public Server(ServerSocket serverSocket) throws IOException {
+        this.serverSocket = serverSocket;
+    }
+
+    /**
+     * Runnable for multithreaded client handling.
+     */
+    private class ClientProcessor implements Runnable {
+        /**
+         * Client's socket.
+         */
+        private Socket socket;
+
+        private ClientProcessor(Socket socket) {
+            this.socket = socket;
+        }
+
+        @Override
+        public void run() {
+            try (
+                    DataInputStream in = new DataInputStream(socket.getInputStream());
+                    DataOutputStream out = new DataOutputStream(socket.getOutputStream())
+            ) {
+                while (true) {
+                    int command = in.readInt();
+                    String path = in.readUTF();
+
+                    if (command == 0) {
+                        out.writeInt(CLOSE_CONNECTION.ordinal());
+                        break;
+                    }
+
+                    switch (command) {
+                        case 1: {
+                            Future<FolderDescription> result = folderDescriber.submit(new FolderDescriptionCallable(path));
+                            FolderDescription description;
+                            try {
+                                description = result.get();
+                            } catch (Exception e) {
+                                description = null;
+                            }
+                            out.writeInt(FOLDER_DESCRIPTION.ordinal());
+                            writeFolderDescription(description, out);
+                            break;
+                        }
+                        case 2: {
+                            out.writeInt(FILE_SEND.ordinal());
+                            sendFile(path, out);
+                            break;
+                        }
+                        default: {
+                            out.writeInt(INVALID_COMMAND.ordinal());
+                        }
+                    }
+                }
+            }
+            catch (IOException e) { }
+            finally {
+                try {
+                    socket.close();
+                } catch (IOException ee) {
+                    ee.printStackTrace();
+                }
+            }
+        }
+    }
+
+    /**
+     * Callable for getting FolderDescription in a ThreadPool.
+     */
+    private class FolderDescriptionCallable implements Callable<FolderDescription> {
+
+        /**
+         * Path to folder.
+         */
+        private String path;
+
+        private FolderDescriptionCallable(String path) {
+            this.path = path;
+        }
+
+        @Override
+        public FolderDescription call() throws Exception {
+            return FolderDescription.describeFolder(path);
+        }
+    }
+
+    /**
+     * Starts the server.
+     */
+    public void start() {
+        while(true) {
+            try {
+                Socket socket = serverSocket.accept();
+                new Thread(new ClientProcessor(socket)).start();
+            } catch (IOException e) {
+                e.printStackTrace();
+            }
+        }
+    }
+
+    /**
+     * Writes FolderDescription to DataOutputStream.
+     * @param description description to write
+     * @param out output stream to write to
+     */
+    public void writeFolderDescription(FolderDescription description, DataOutputStream out) throws IOException {
+        int size;
+        if (description == null) {
+            size = 0;
+        } else {
+            size = description.getSize();
+        }
+        out.writeInt(size);
+        if (size == 0) {
+            return;
+        }
+        for (FolderDescription.FileDescription fileDescription : description.getFiles()) {
+            out.writeUTF(fileDescription.getName());
+            out.writeBoolean(fileDescription.isDir());
+        }
+    }
+
+    /**
+     * Sends file over ServerSocket's DataOutputStream.
+     * @param name filename
+     * @param out output stream to write to
+     */
+    private 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);
+            }
+        }
+    }
+
+    public static void main(String[] args) {
+        ServerSocket serverSocket;
+        try {
+            serverSocket = new ServerSocket(8080);
+            new Server(serverSocket).start();
+        } catch (IOException e) {
+            System.err.println("Error creating server");
+            return;
+        }
+    }
+
+}
diff --git a/SimpleFTP/src/test/java/ru/spbau/dkaznacheev/simpleftp/FolderDescriptionTest.java b/SimpleFTP/src/test/java/ru/spbau/dkaznacheev/simpleftp/FolderDescriptionTest.java
new file mode 100644
index 0000000..85d4b8b
--- /dev/null
+++ b/SimpleFTP/src/test/java/ru/spbau/dkaznacheev/simpleftp/FolderDescriptionTest.java
@@ -0,0 +1,11 @@
+package ru.spbau.dkaznacheev.simpleftp;
+
+import org.junit.Test;
+
+public class FolderDescriptionTest {
+    @Test
+    public void folderDescSimpleTest() {
+        FolderDescription desc = FolderDescription.describeFolder("./");
+        desc.print();
+    }
+}
diff --git a/SimpleFTP/src/test/java/ru/spbau/dkaznacheev/simpleftp/SimpleFTPTest.java b/SimpleFTP/src/test/java/ru/spbau/dkaznacheev/simpleftp/SimpleFTPTest.java
new file mode 100644
index 0000000..fb6f358
--- /dev/null
+++ b/SimpleFTP/src/test/java/ru/spbau/dkaznacheev/simpleftp/SimpleFTPTest.java
@@ -0,0 +1,27 @@
+package ru.spbau.dkaznacheev.simpleftp;
+
+import org.junit.Test;
+
+import java.io.*;
+import java.net.ServerSocket;
+import java.net.Socket;
+import java.nio.file.Files;
+import java.nio.file.Paths;
+import java.util.function.BiConsumer;
+import java.util.function.Function;
+import java.util.regex.PatternSyntaxException;
+
+import static org.junit.Assert.*;
+import static ru.spbau.dkaznacheev.simpleftp.ResponseCode.FILE_SEND;
+import static ru.spbau.dkaznacheev.simpleftp.ResponseCode.FOLDER_DESCRIPTION;
+
+public class SimpleFTPTest {
+    @Test
+    public void correctFolderDescription() throws Throwable {
+        FolderDescription description = FolderDescription.describeFolder("src/test/resources");
+        assertEquals(1, description.getSize());
+        assertEquals(1, description.getFiles().length);
+        assertEquals("testFile", description.getFiles()[0].getName());
+        assertEquals(false, description.getFiles()[0].isDir());
+    }
+}
\ No newline at end of file
diff --git a/SimpleFTP/src/test/resources/testFile b/SimpleFTP/src/test/resources/testFile
new file mode 100644
index 0000000..30d74d2
--- /dev/null
+++ b/SimpleFTP/src/test/resources/testFile
@@ -0,0 +1 @@
+test
\ No newline at end of file
diff --git a/SimpleFTP/testFile b/SimpleFTP/testFile
new file mode 100644
index 0000000..5057510
Binary files /dev/null and b/SimpleFTP/testFile differ