Develop Java Apps

Maven

To build your Java application using the YugabyteDB version of the Jedis driver, add the following Maven dependency to your application:

  1. <dependency>
  2.   <groupId>com.yugabyte</groupId>
  3.   <artifactId>jedis</artifactId>
  4.   <version>2.9.0-yb-16</version>
  5. </dependency>

Working example

Prerequisites

This tutorial assumes that you have:

  • installed YugabyteDB, created a universe and are able to interact with it using the Redis shell. If not, please follow these steps in the quick start guide.
  • installed JDK version 1.8+ and maven 3.3+

Creating the maven build file

Create a maven build file pom.xml and add the following content into it.

  1. <?xml version="1.0"?>
  2. <!-- Copyright (c) Yugabyte, Inc. -->
  3. <project
  4.   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd"
  5.   xmlns="http://maven.apache.org/POM/4.0.0"
  6.   xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  7.   <modelVersion>4.0.0</modelVersion>
  9.   <groupId>com.yugabyte.sample.apps</groupId>
  10.   <artifactId>hello-world</artifactId>
  11.   <version>1.0</version>
  12.   <packaging>jar</packaging>
  14.   <dependencies>
  15.     <dependency>
  16.       <groupId>com.yugabyte</groupId>
  17.       <artifactId>jedis</artifactId>
  18.       <version>2.9.0-yb-16</version>
  19.     </dependency>
  20.   </dependencies>
  22.   <build>
  23.     <plugins>
  24.       <plugin>
  25.         <groupId>org.apache.maven.plugins</groupId>
  26.         <artifactId>maven-dependency-plugin</artifactId>
  27.         <version>2.1</version>
  28.         <executions>
  29.           <execution>
  30.             <id>copy-dependencies</id>
  31.             <phase>prepare-package</phase>
  32.             <goals>
  33.               <goal>copy-dependencies</goal>
  34.             </goals>
  35.             <configuration>
  36.               <outputDirectory>${project.build.directory}/lib</outputDirectory>
  37.               <overWriteReleases>true</overWriteReleases>
  38.               <overWriteSnapshots>true</overWriteSnapshots>
  39.               <overWriteIfNewer>true</overWriteIfNewer>
  40.             </configuration>
  41.           </execution>
  42.         </executions>
  43.       </plugin>
  44.     </plugins>
  45.   </build>
  46. </project>

Writing a HelloWorld Redis app

Create the appropriate directory structure as expected by maven.

  1. $ mkdir -p src/main/java/com/yugabyte/sample/apps

Copy the following contents into the file src/main/java/com/yugabyte/sample/apps/YBRedisHelloWorld.java.

  1. package com.yugabyte.sample.apps;
  3. import java.util.HashMap;
  4. import java.util.Map;
  5. import redis.clients.jedis.Jedis;
  7. public class YBRedisHelloWorld {
  8.   public static void main(String[] args) {
  9.     try {
  10.       // Create a Jedis client.
  11.       Jedis jedisClient = new Jedis("127.0.0.1");
  13.       // Prepare the employee information to insert.
  14.       String userid = "1";
  15.       Map<String, String> userProfile = new HashMap<String, String>();
  16.       userProfile.put("name", "John");
  17.       userProfile.put("age", "35");
  18.       userProfile.put("language", "Redis");
  20.       // Insert the data.
  21.       String result = jedisClient.hmset(userid, userProfile);
  22.       System.out.println("HMSET returned " + result + ": id=1, name=John, age=35, language=Redis");
  24.       // Query the data.
  25.       Map<String, String> userData = jedisClient.hgetAll(userid);
  26.       System.out.println("Query result: name=" + userData.get("name") +
  27.                          ", age=" + userData.get("age") + ", language=" + userData.get("language"));
  29.       // Close the client.
  30.       jedisClient.close();
  31.     } catch (Exception e) {
  32.         System.err.println("Error: " + e.getMessage());
  33.     }
  34.   }
  35. }

Building and running the app

To build the application, just run the following command.

  1. $ mvn package

To run the program, do the following.

  1. % java -cp "target/hello-world-1.0.jar:target/lib/*" com.yugabyte.sample.apps.YBRedisHelloWorld

You should see the following as the output.

  1. HMSET returned OK: id=1, name=John, age=35, language=Redis
  2. Query result: name=John, age=35, language=Redis