Java developers are usually more comfortable with writing Java classes, than with writing SQL. Hence many (greenfield) projects are written with a Java-First approach, which means that you create your Java class before you create the corresponding database table.
Hibernate
Hibernate is a powerful, ultra-high performance object/relational persistence and query service for Java. Hibernate lets you develop persistent objects following common Java idioms - including association, inheritance, polymorphism, composition and the Java collections framework. Extremely fine-grained, richly typed object models are possible. The Hibernate Query Language, designed as a "minimal" object-oriented extension to SQL, provides an elegant bridge between the object and relational worlds. Hibernate is now the most popular ORM solution for Java.
Spring Data
Spring Data’s mission is to provide a familiar and consistent, Spring-based programming model for data access while still retaining the special traits of the underlying data store. It makes it easy to use data access technologies, relational and non-relational databases, map-reduce frameworks, and cloud-based data services. This is an umbrella project which contains many subprojects that are specific to a given database.
GORM
GORM is the data access toolkit used by Grails and provides a rich set of APIs for accessing relational and non-relational data including implementations for Hibernate (SQL), MongoDB, Neo4j, Cassandra, an in-memory ConcurrentHashMap for testing and an automatic GraphQL schema generator.
Java Persistence Api
The Java Persistence API (JPA) is the Java standard for mapping Java objects to a relational database. Even though proprietary mapping products like Hibernate and TopLink still exist, they are now focused on providing their functionality through the JPA API, allowing all applications to be portable across JPA implementations.
Micronaut Data
Micronaut Data is a database access toolkit that uses Ahead of Time (AoT) compilation to pre-compute queries for repository interfaces that are then executed by a thin, lightweight runtime layer. Micronaut Data is inspired by GORM and Spring Data, however improves on those solutions in the following ways: 1. No runtime model. 2. No query translation. 3. No Reflection or Runtime Proxies. 4. Type Safety.