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Hibernate Criteria API

~1 min read · Hibernate
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The Criteria API is an alternative to HQL (Hibernate Query Language) for writing dynamic queries in Hibernate. Instead of writing queries as plain strings, Criteria API allows type-safe, object-oriented queries.


Why Use Criteria API?

✅ Dynamic Queries – Queries can be built at runtime.

✅ Type-Safe – Uses Java classes instead of raw strings.

✅ No String-Based HQL – Avoids syntax errors from misspelled query strings.

✅ Better Maintainability – Queries are constructed programmatically.

Setting Up Criteria API

To use Criteria API, you need to get a Session and use the CriteriaBuilder class.

HibernateUtil.java
import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; public class HibernateUtil { private static final SessionFactory sessionFactory = buildSessionFactory(); private static SessionFactory buildSessionFactory() { try { return new Configuration() .configure("hibernate.cfg.xml") .addAnnotatedClass(Person.class) .addAnnotatedClass(Course.class) .buildSessionFactory(); } catch (Throwable ex) { System.err.println("SessionFactory creation failed: " + ex); throw new ExceptionInInitializerError(ex); } } public static SessionFactory getSessionFactory() { return sessionFactory; } public static Session getSession() { return sessionFactory.openSession(); // Opens a new session when needed } public static void shutdown() { sessionFactory.close(); // Close SessionFactory when the application shuts down } }
Session session = HibernateUtil.getSession(); CriteriaBuilder builder = session.getCriteriaBuilder();

Fetch All Records (Equivalent to SELECT * FROM table):

Session session = HibernateUtil.getSession(); CriteriaBuilder builder = session.getCriteriaBuilder(); CriteriaQuery query = builder.createQuery(Student.class); Root root = query.from(Student.class); query.select(root); List students = session.createQuery(query).getResultList(); System.out.println(students); session.close();

Applying WHERE Condition

🔹 Fetch Students with Age > 20

🔹 Equivalent SQL: SELECT * FROM student WHERE age > 20;

CriteriaBuilder builder = session.getCriteriaBuilder(); CriteriaQuery query = builder.createQuery(Student.class); Root root = query.from(Student.class); query.select(root).where(builder.gt(root.get("age"), 20)); List students = session.createQuery(query).getResultList();

Applying Multiple Conditions (AND, OR)

🔹 Fetch Students where age > 20 AND name starts with 'A'

🔹 Equivalent SQL: SELECT * FROM student WHERE age > 20 AND name LIKE 'A%';

CriteriaBuilder builder = session.getCriteriaBuilder(); CriteriaQuery query = builder.createQuery(Student.class); Root root = query.from(Student.class); Predicate agePredicate = builder.gt(root.get("age"), 20); Predicate namePredicate = builder.like(root.get("name"), "A%"); query.select(root).where(builder.and(agePredicate, namePredicate)); List students = session.createQuery(query).getResultList();

Sorting Results (ORDER BY)

🔹 Sort Students by Age (Ascending)

🔹 Equivalent SQL: SELECT * FROM student ORDER BY age ASC;


CriteriaBuilder builder = session.getCriteriaBuilder(); CriteriaQuery query = builder.createQuery(Student.class); Root root = query.from(Student.class); query.select(root).orderBy(builder.asc(root.get("age"))); List students = session.createQuery(query).getResultList();

🔹 Sort Students by Name (Descending)

🔹 Equivalent SQL: SELECT * FROM student ORDER BY name DESC;

query.orderBy(builder.desc(root.get("name")));

Fetching Specific Columns

🔹 Select Only Name and Age

🔹 Equivalent SQL: SELECT name, age FROM student;

CriteriaBuilder builder = session.getCriteriaBuilder(); CriteriaQuery query = builder.createQuery(Object[].class); Root root = query.from(Student.class); query.multiselect(root.get("name"), root.get("age")); List results = session.createQuery(query).getResultList(); for (Object[] row : results) { System.out.println("Name: " + row[0] + ", Age: " + row[1]); }

Aggregation Functions (COUNT, SUM, AVG, MIN, MAX)

🔹 Count Total Students

🔹 Equivalent SQL: SELECT COUNT(*) FROM student;

CriteriaBuilder builder = session.getCriteriaBuilder(); CriteriaQuery query = builder.createQuery(Long.class); Root root = query.from(Student.class); query.select(builder.count(root)); Long count = session.createQuery(query).getSingleResult(); System.out.println("Total Students: " + count);

🔹 Find Average Age

🔹 Equivalent SQL: SELECT AVG(age) FROM student;

query.select(builder.avg(root.get("age")));

Using Joins in Criteria API

🔹 Inner Join (Fetch Students with their Courses)

🔹 Equivalent SQL: SELECT * FROM student JOIN course ON student.id = course.student_id;

CriteriaBuilder builder = session.getCriteriaBuilder(); CriteriaQuery query = builder.createQuery(Student.class); Root root = query.from(Student.class); Join courseJoin = root.join("courses"); // Assuming 'courses' is a List query.select(root); List students = session.createQuery(query).getResultList();

🔹 Left Join (Fetch Students Even If They Have No Courses)

🔹 Equivalent SQL: SELECT * FROM student LEFT JOIN course ON student.id = course.student_id;

Join courseJoin = root.join("courses", JoinType.LEFT);

Pagination (Limit & Offset)

Hibernate Criteria API allows pagination using setFirstResult() and setMaxResults().

🔹 Fetch Page 2 (5 Records Per Page)

🔹 Equivalent SQL: SELECT * FROM student LIMIT 5 OFFSET 5;

List students = session.createQuery(query) .setFirstResult(5) // Skip first 5 records (Page 2) .setMaxResults(5) // Fetch next 5 records .getResultList();

Deleting Data using Criteria API

🔹 Equivalent SQL: DELETE FROM student WHERE name = 'John';

CriteriaBuilder builder = session.getCriteriaBuilder(); CriteriaDelete deleteQuery = builder.createCriteriaDelete(Student.class); Root root = deleteQuery.from(Student.class); deleteQuery.where(builder.equal(root.get("name"), "John")); session.beginTransaction(); int deletedCount = session.createQuery(deleteQuery).executeUpdate(); session.getTransaction().commit();

Updating Data using Criteria API

🔹 Equivalent SQL: UPDATE student SET age = 25 WHERE name = 'Alice';

CriteriaBuilder builder = session.getCriteriaBuilder(); CriteriaUpdate updateQuery = builder.createCriteriaUpdate(Student.class); Root root = updateQuery.from(Student.class); updateQuery.set("age", 25).where(builder.equal(root.get("name"), "Alice")); session.beginTransaction(); int updatedCount = session.createQuery(updateQuery).executeUpdate(); session.getTransaction().commit();

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