Following examples shows how to use JPQL LIKE keyword to apply wildcard pattern matching.

% wildcard is used to match zero or more characters.

_ wildcard is used to match any single character.

The optional ESCAPE keyword at the end specifies an escape character of our choice. It is used if we want to use % or _ as literal rather than wildcards.

Examples

Entity

@Entity
public class Employee {
    @Id
    @GeneratedValue
    private long id;
    private String name;
    private String dept;
    private long salary;
    .............
}

Using LIKE expression

public class ExampleMain {
    private static EntityManagerFactory entityManagerFactory =
            Persistence.createEntityManagerFactory("example-unit");

    public static void main(String[] args) {
        try {
            persistEmployees();
            findEmployeeBySalary();
            findEmployeeByName();
            //not like and using parameter
            findEmployeeByName2();
            //escaping
            findEmployeeByDept();
        } finally {
            entityManagerFactory.close();
        }
    }

    public static void persistEmployees() {
        Employee employee1 = Employee.create("Diana", "IT", 3000);
        Employee employee2 = Employee.create("Rose", "Sales", 2000);
        Employee employee3 = Employee.create("Denise", "Admin", 4000);
        Employee employee4 = Employee.create("Mike", "H_R", 3500);
        EntityManager em = entityManagerFactory.createEntityManager();
        em.getTransaction().begin();
        em.persist(employee1);
        em.persist(employee2);
        em.persist(employee3);
        em.persist(employee4);
        em.getTransaction().commit();
        em.close();
    }

    private static void findEmployeeBySalary() {
        System.out.println("-- Employees with salary LIKE _500 --");
        EntityManager em = entityManagerFactory.createEntityManager();
        Query query = em.createQuery(
                "SELECT e FROM Employee e WHERE e.salary LIKE '_500' order by e.salary");
        List<Employee> resultList = query.getResultList();
        resultList.forEach(System.out::println);
        em.close();
    }

    private static void findEmployeeByName() {
        System.out.println("-- Employees name LIKE D% --");
        EntityManager em = entityManagerFactory.createEntityManager();
        Query query = em.createQuery(
                "SELECT e FROM Employee e WHERE e.name LIKE 'D%'");
        List<Employee> resultList = query.getResultList();
        resultList.forEach(System.out::println);
        em.close();
    }

    private static void findEmployeeByName2() {
        System.out.println("-- Employees name NOT LIKE D% --");
        EntityManager em = entityManagerFactory.createEntityManager();
        Query query = em.createQuery(
                "SELECT e FROM Employee e WHERE e.name NOT LIKE :nameStartsWith");
        query.setParameter("nameStartsWith", "D%");
        List<Employee> resultList = query.getResultList();
        resultList.forEach(System.out::println);
        em.close();
    }

    private static void findEmployeeByDept() {
        System.out.println("-- Employees dept LIKE '%@_%' ESCAPE '@' --");
        EntityManager em = entityManagerFactory.createEntityManager();
        //our escape character is '@'
        Query query = em.createQuery(
                "SELECT e FROM Employee e WHERE e.dept LIKE '%@_%' ESCAPE '@'");
        List<Employee> resultList = query.getResultList();
        resultList.forEach(System.out::println);
        em.close();
    }
}

-- Employees with salary LIKE _500 --
Employee{id=4, name='Mike', dept='H_R', salary=3500}
-- Employees name LIKE D% --
Employee{id=1, name='Diana', dept='IT', salary=3000}
Employee{id=3, name='Denise', dept='Admin', salary=4000}
-- Employees name NOT LIKE D% --
Employee{id=2, name='Rose', dept='Sales', salary=2000}
Employee{id=4, name='Mike', dept='H_R', salary=3500}
-- Employees dept LIKE '%@_%' ESCAPE '@' --
Employee{id=4, name='Mike', dept='H_R', salary=3500}

Example Project

Dependencies and Technologies Used:

• h2 1.4.197: H2 Database Engine.
• hibernate-core 5.2.13.Final: The core O/RM functionality as provided by Hibernate.
  Implements javax.persistence:javax.persistence-api version 2.1
• JDK 1.8
• Maven 3.3.9