How can multiple data sources be configured in Java?

There are several methods for configuring multiple data sources in Java.

1. The AbstractRoutingDataSource class in the Spring framework allows for dynamic switching of data sources at runtime, enabling the choice of which data source to use based on requirements.
2. Configuring multiple data sources using JPA: JPA, short for Java Persistence API, is a Java technology for persistence that can integrate with various data sources. Configuring multiple PersistenceUnits allows for setting up multiple data sources.
3. Configuring multiple data sources using MyBatis: MyBatis is a persistence framework that can integrate with multiple databases. Multiple data sources can be configured by setting up multiple SqlSessionFactory instances.
4. Configuring multiple data sources with Druid connection pool: Druid is a high-performance database connection pool that can be integrated with various data sources. Configuring multiple data sources can be achieved by setting up multiple DataSources.

The above are some common methods for configuring multiple data sources in Java, the specific method to choose depends on the project’s requirements and technology stack.