Develop Java Apps

    Working example

    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+
    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>
    21.   <build>
    22.     <plugins>
    23.       <plugin>
    24.         <groupId>org.apache.maven.plugins</groupId>
    25.         <artifactId>maven-dependency-plugin</artifactId>
    26.         <version>2.1</version>
    28.           <execution>
    29.             <id>copy-dependencies</id>
    30.             <phase>prepare-package</phase>
    31.             <goals>
    32.               <goal>copy-dependencies</goal>
    33.             </goals>
    34.             <configuration>
    35.               <outputDirectory>${project.build.directory}/lib</outputDirectory>
    36.               <overWriteReleases>true</overWriteReleases>
    37.               <overWriteSnapshots>true</overWriteSnapshots>
    38.               <overWriteIfNewer>true</overWriteIfNewer>
    39.             </configuration>
    40.           </execution>
    41.         </executions>
    42.       </plugin>
    43.     </plugins>
    44.   </build>
    45. </project>

    Create the appropriate directory structure as expected by maven.

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

    To build the application, just run the following command.

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

    You should see the following as the output.