{"id":736,"date":"2012-11-11T19:48:31","date_gmt":"2012-11-11T19:48:31","guid":{"rendered":"http:\/\/ilias-laptop\/examples\/enterprise-java\/jpa\/jpa-crud-example\/"},"modified":"2019-02-27T14:53:26","modified_gmt":"2019-02-27T12:53:26","slug":"jpa-crud-example","status":"publish","type":"post","link":"https:\/\/examples.javacodegeeks.com\/java-development\/enterprise-java\/jpa\/jpa-crud-example\/","title":{"rendered":"JPA CRUD Example"},"content":{"rendered":"

This is an example of how to perform CRUD functionality in JPA. The Java Persistence API provides Java developers with an object\/relational mapping facility for managing relational data in Java applications.
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\nHere, we are using JPA to perform create, delete, update and delete methods, as shown below:<\/p>\n

Employee Class<\/h3>\n

The Employee<\/code> class is an entity class, annotated with the javax.persistence.Entity<\/code> annotation. It uses the @Id<\/code> annotation to define its id property.<\/p>\n

package employeeDB;import javax.persistence.*;\n \n@Entity\npublicclass Employee {\n \n    @Id String name;\n    Double salary;\n \n    public Employee()\n    {\n \n    }\n \n    public Employee (String name, Double Salary)\n    {\n\n  this.name=name;\n\n  this.salary=Salary;\n    }\n \n    publicvoid setSalary(Double Salary)\n    {\n\n  this.salary=Salary;\n    }\n \n    publicString toString()\n    {\n\n  return\"Name: \"+name+\"nSalary: \"+salary ;\n    }\n \n}\n<\/pre>\n
ExampleProgram<\/h3>\n
In the ExampleProgram<\/code> we create four methods, displayAll()<\/code>, insert()<\/code>, delete(String name)<\/code> and modify(String name, Double Salary)<\/code> to perform the CRUD functionality. In all methods we use an EntityManager, using the createEntityManager()<\/code> API method. The getTransaction().begin()<\/code> and getTransaction().commit()<\/code> methods are used before and after the EntityManager<\/code> invokes a method so that a transaction begins and ends.<\/p>\n