Next, create a Java project in Eclipse IDE for migrating Cassandra database data to MongoDB database.
- Select File >■ New >■ Other.
- In the New window, select Maven ► Maven Project and click on Next as shown in Figure 6-3.
- The New Maven Project wizard gets started. Select the Create a simple project check box and the Use default Workspace location check box and click on Next as shown in Figure 6-4.
- In Configure project, specify the following and then click on Finish as shown in Figure 6-5.
- Group Id: com.mongodb.migration
- Artifact Id: CassandraToMongoDB
- Version: 1.0.0
- Packaging: jar
- Name: CassandraToMongoDB
A Maven Project gets created in Eclipse IDE as shown in Figure 6-6.
Now we need to create two Java classes for the migration: one to create the initial data in Cassandra and the other to migrate the data to MongoDB.
- To create a Java class click on File ► New ► Other.
- In the New window, select Java ► Class and click on Next as shown in Figure 6-7.
- In New Java Class wizard select the Source folder as CassandraToMongoDB/ src/main/java and specify Package as mongodb and class name as CreateCassandraDatabase. Select the check box to create method stub public static void main(String[] args). Click on Finish as shown in Figure 6-8.
4. Similarly create a Java class MigrateCassandraToMongoDB as shown in Figure 6-9.
he two Java classes are shown in the Package Explorer in Figure 6-10.
We need to add some dependencies to the pom.xml. Add the following dependencies listed in Table 6-1; some of the dependencies are indicated as being included with the Apache Cassandra Project dependency and should not be added separately.
The pom.xml is listed below.
<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>
<groupId>com.mongodb.migration</groupId>
<artifactId>CassandraToMongoDB</artifactId>
<version>1.0.0</version>
<name>CassandraToMongoDB</name>
<dependencies>
<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongo-java-driver</artifactId>
<version>3.0.3</version>
</dependency>
<dependency>
<groupId>com.datastax.cassandra</groupId>
<artifactId>cassandra-driver-core</artifactId>
<version>2.2.0-rc2</version>
</dependency>
<dependency>
<groupId>org.apache.cassandra</groupId>
<artifactId>cassandra-all</artifactId>
<version>2.2.0</version>
</dependency>
<dependency>
<groupId>commons-beanutils</groupId>
<artifactId>commons-beanutils</artifactId>
<version>1.9.2</version>
</dependency>
<dependency>
<groupId>commons-collections</groupId>
<artifactId>commons-collections</artifactId>
<version>3.2.1</version>
</dependency>
<dependency>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
<version>1.2</version>
</dependency>
</dependencies>
</project>
Some of these dependencies have further dependencies, which get added automatically and should not be added separately. To find the required Jars that get added from the dependencies, right-click on the project node in Package Explorer and select Properties. In Properties select Java Build Path. The Jars added to the migration project are shown in Figure 6-11.
Source: Vohra Deepak (2015), Pro MongoDB™ Development, Apress; 1st ed. edition.