Add Java Client

.gitignore

@@ -1,4 +1,5 @@
 JavaScript/node_modules
+Java/target
 Python/venv
 Python/dist
 Python/buildc

Java/pom.xml

@@ -0,0 +1,45 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <scm>
+        <connection>scm:git:https://github.com/LonaDB/Clients.git</connection>
+        <developerConnection>scm:git:https://github.com/LonaDB/Clients.git</developerConnection>
+        <url>https://github.com/LonaDB/Clients</url>
+    </scm>
+
+    <groupId>org.lona-development.java-client</groupId>
+    <artifactId>LonaDB</artifactId>
+    <version>2.1.3</version>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.fasterxml.jackson.core</groupId>
+            <artifactId>jackson-databind</artifactId>
+            <version>2.13.0</version>
+        </dependency>
+
+        <dependency>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13.1</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-compiler-plugin</artifactId>
+                <version>3.8.1</version>
+                <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+</project>

Java/src/main/java/org/lona_development/java_client/LonaDB.java

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+import java.io.*;
+import java.net.*;
+import java.util.Base64;
+import java.util.Random;
+import javax.crypto.*;
+import javax.crypto.spec.*;
+import java.security.*;
+
+public class LonaDB {
+    private String host;
+    private int port;
+    private String name;
+    private String password;
+
+    public LonaDB(String host, int port, String name, String password) {
+        this.host = host;
+        this.port = port;
+        this.name = name;
+        this.password = password;
+    }
+
+    private String makeId(int length) {
+        StringBuilder result = new StringBuilder();
+        String characters = "ABCDEFGHIJKLMNOPQRSTUVWXYZ1234567890abcdefghijklmnopqrstuvwxyz";
+        Random rand = new Random();
+        int counter = 0;
+
+        while (counter < length) {
+            result.append(characters.charAt(rand.nextInt(characters.length())));
+            counter++;
+        }
+
+        return result.toString();
+    }
+
+    private String encryptPassword(String password, String key) throws Exception {
+        byte[] iv = new byte[16];
+        new SecureRandom().nextBytes(iv);
+        Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
+        cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(Base64.getDecoder().decode(key), "AES"), new IvParameterSpec(iv));
+        byte[] encrypted = cipher.doFinal(password.getBytes());
+        return bytesToHex(iv) + ":" + bytesToHex(encrypted);
+    }
+
+    private String bytesToHex(byte[] bytes) {
+        StringBuilder result = new StringBuilder();
+        for (byte b : bytes) {
+            result.append(String.format("%02x", b));
+        }
+        return result.toString();
+    }
+
+    public String sendRequest(String action, String data) throws Exception {
+        String processID = makeId(5);
+        String encryptionKey = Base64.getEncoder().encodeToString(MessageDigest.getInstance("SHA-256").digest(processID.getBytes()));
+
+        String encryptedPassword = encryptPassword(password, encryptionKey);
+
+        String request = String.format("{\"action\":\"%s\",\"login\":{\"name\":\"%s\",\"password\":\"%s\"},\"process\":\"%s\",%s}", action, name, encryptedPassword, processID, data);
+
+        Socket socket = new Socket(host, port);
+        OutputStream out = socket.getOutputStream();
+        PrintWriter writer = new PrintWriter(out, true);
+        writer.println(request);
+
+        BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
+        StringBuilder response = new StringBuilder();
+        String line;
+        while ((line = in.readLine()) != null) {
+            response.append(line);
+        }
+
+        socket.close();
+
+        return response.toString();
+    }
+
+    public String createFunction(String name, String content) throws Exception {
+        String data = String.format("{\"function\":{\"name\":\"%s\",\"content\":\"%s\"}}", name, content);
+        return sendRequest("add_function", data);
+    }
+
+    public String executeFunction(String name) throws Exception {
+        String data = String.format("{\"name\":\"%s\"}", name);
+        return sendRequest("execute_function", data);
+    }
+
+    public String getTables(String user) throws Exception {
+        String data = String.format("{\"user\":\"%s\"}", user);
+        return sendRequest("get_tables", data);
+    }
+
+    public String getTableData(String table) throws Exception {
+        String data = String.format("{\"table\":\"%s\"}", table);
+        return sendRequest("get_table_data", data);
+    }
+
+    public String deleteTable(String table) throws Exception {
+        String data = String.format("{\"table\":{\"name\":\"%s\"}}", table);
+        return sendRequest("delete_table", data);
+    }
+
+    public String createTable(String table) throws Exception {
+        String data = String.format("{\"table\":{\"name\":\"%s\"}}", table);
+        return sendRequest("create_table", data);
+    }
+
+    public String set(String table, String name, String value) throws Exception {
+        String data = String.format("{\"table\":{\"name\":\"%s\"},\"variable\":{\"name\":\"%s\",\"value\":\"%s\"}}", table, name, value);
+        return sendRequest("set_variable", data);
+    }
+
+    public String delete(String table, String name) throws Exception {
+        String data = String.format("{\"table\":{\"name\":\"%s\"},\"variable\":{\"name\":\"%s\"}}", table, name);
+        return sendRequest("remove_variable", data);
+    }
+
+    public String get(String table, String name) throws Exception {
+        String data = String.format("{\"table\":{\"name\":\"%s\"},\"variable\":{\"name\":\"%s\"}}", table, name);
+        return sendRequest("get_variable", data);
+    }
+
+    public String getUsers() throws Exception {
+        return sendRequest("get_users", "{}");
+    }
+
+    public String createUser(String name, String pass) throws Exception {
+        String data = String.format("{\"user\":{\"name\":\"%s\",\"password\":\"%s\"}}", name, pass);
+        return sendRequest("create_user", data);
+    }
+
+    public String deleteUser(String name) throws Exception {
+        String data = String.format("{\"user\":{\"name\":\"%s\"}}", name);
+        return sendRequest("delete_user", data);
+    }
+
+    public String checkPassword(String name, String pass) throws Exception {
+        String data = String.format("{\"checkPass\":{\"name\":\"%s\",\"pass\":\"%s\"}}", name, pass);
+        return sendRequest("check_password", data);
+    }
+
+    public String checkPermission(String name, String permission) throws Exception {
+        String data = String.format("{\"permission\":{\"user\":\"%s\",\"name\":\"%s\"}}", name, permission);
+        return sendRequest("check_permission", data);
+    }
+
+    public String removePermission(String name, String permission) throws Exception {
+        String data = String.format("{\"permission\":{\"user\":\"%s\",\"name\":\"%s\"}}", name, permission);
+        return sendRequest("remove_permission", data);
+    }
+
+    public String getPermissionsRaw(String name) throws Exception {
+        String data = String.format("{\"user\":\"%s\"}", name);
+        return sendRequest("get_permissions_raw", data);
+    }
+
+    public String addPermission(String name, String permission) throws Exception {
+        String data = String.format("{\"permission\":{\"user\":\"%s\",\"name\":\"%s\"}}", name, permission);
+        return sendRequest("add_permission", data);
+    }
+
+    public String eval(String func) throws Exception {
+        String data = String.format("{\"function\":\"%s\"}", func);
+        return sendRequest("eval", data);
+    }
+}