In this post, we will see Spring Data JPA IsNull Example using Spring Boot and Oracle. We will see how to use IsNull keyword to define Query Methods(Query creation from method names).
Let’s say we have an entity called Student.java.
package com.javatute.entity;
@Entity
public class Student {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private int id;
@Column(name = "name")
private String name;
@Column(name = "roll_number")
private String rollNumber;
@Column(name = "university")
String university;
}
In the database, we have some records as below.
Below Query method will return all record which name is null.
public List<Student> findByNameIsNull();
Generated Query.
Hibernate: select student0_.id as id1_0_, student0_.name as name2_0_, student0_.roll_number as roll_number3_0_, student0_.university as university4_0_ from student student0_ where student0_.name is null
Below Query method will return all record which name is john or null.
public List<Student> findByNameOrNameIsNull(String name);
Hibernate: select student0_.id as id1_0_, student0_.name as name2_0_, student0_.roll_number as roll_number3_0_, student0_.university as university4_0_ from student student0_ where student0_.name=? or student0_.name is null
Below Query method will return all record which name is john or null and the university is rgtu.
public List<Student> findByNameAndUniversityOrNameIsNull(String name, String university);
Hibernate: select student0_.id as id1_0_, student0_.name as name2_0_, student0_.roll_number as roll_number3_0_, student0_.university as university4_0_ from student student0_ where student0_.name=? and student0_.university=? or student0_.name is null
Let’s see an example of Spring Data JPA IsNull Example.
Open eclipse and create maven project, Don’t forget to check ‘Create a simple project (skip)’ click on next. Fill all details(GroupId – springdataisnull, ArtifactId – springdataisnull and name – springdataisnull) and click on finish. Keep packaging as the jar.
Modify pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>springdataisnull</groupId>
<artifactId>springdataisnull</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>springdataisnull</name>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.2.RELEASE</version>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>com.oracle</groupId>
<artifactId>ojdbc6</artifactId>
<version>11.2.0.3</version>
</dependency>
</dependencies>
<build>
<finalName>${project.artifactId}</finalName>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<fork>true</fork>
<executable>C:\Program Files\Java\jdk1.8.0_131\bin\javac.exe</executable>
</configuration>
</plugin>
</plugins>
</build>
</project>
Note – In pom.xml we have defined javac.exe path in configuration tag. You need to change accordingly i.e where you have installed JDK.
If you see any error for oracle dependency then follow these steps.
Directory structure –
Student.java
package com.javatute.entity;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
@Entity
public class Student {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
private int id;
@Column(name = "name")
private String name;
@Column(name = "roll_number")
private String rollNumber;
@Column(name = "university")
String university;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getRollNumber() {
return rollNumber;
}
public void setRollNumber(String rollNumber) {
this.rollNumber = rollNumber;
}
public String getUniversity() {
return university;
}
public void setUniversity(String university) {
this.university = university;
}
}
StudentController.java
package com.javatute.controller;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.RestController;
import com.javatute.entity.Student;
import com.javatute.service.StudentService;
@RestController
@RequestMapping(value = "/student")
public class StudentController {
@Autowired
private StudentService studentService;
@RequestMapping(value = "/saveall", method = RequestMethod.POST)
@ResponseBody
public List<Student> saveAllStudents(@RequestBody List<Student> studentList) {
List<Student> studentResponse = (List<Student>) studentService.saveAllStudent(studentList);
return studentResponse;
}
@RequestMapping(value = "/findbynameisnull", method = RequestMethod.GET)
@ResponseBody
public List<Student> findByNameIsNull() {
List<Student> studentResponse = (List<Student>) studentService.findByNameIsNull();
return studentResponse;
}
@RequestMapping(value = "/findbynameanduniversityornameisnull/{name}/{university}", method = RequestMethod.GET)
@ResponseBody
public List<Student> findByNameAndUniversityOrNameIsNull(@PathVariable String name, @PathVariable String university) {
List<Student> studentResponse = (List<Student>) studentService.findByNameAndUniversityOrNameIsNull(name, university);
return studentResponse;
}
}
Note – See more details about @Controller and RestController here.
StudentRepository.java – interface
package com.javatute.repository;
import java.io.Serializable;
import java.util.List;
import org.springframework.data.repository.CrudRepository;
import org.springframework.stereotype.Repository;
import com.javatute.entity.Student;
@Repository
public interface StudentRepository extends CrudRepository<Student, Serializable> {
public List<Student> findByNameIsNull();
public List<Student> findByNameOrNameIsNull(String name);
public List<Student> findByNameAndUniversityOrNameIsNull(String name, String university);
}
StudentService.java – interface
package com.javatute.service;
import java.util.List;
import org.springframework.stereotype.Component;
import com.javatute.entity.Student;
@Component
public interface StudentService {
public List<Student> saveAllStudent(List<Student> studentList);
public List<Student> findByNameIsNull();
public List<Student> findByNameOrNameIsNull(String name);
public List<Student> findByNameAndUniversityOrNameIsNull(String name, String university);
}
Note – See here more about @Component, @Controller, @Service and @Repository annotations here.
StudentServiceImpl.java
package com.javatute.impl;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import com.javatute.entity.Student;
import com.javatute.repository.StudentRepository;
import com.javatute.service.StudentService;
@Service("studentServiceImpl")
public class StudentServiceImpl implements StudentService {
@Autowired
private StudentRepository studentRepository;
@Transactional
public List<Student> saveAllStudent(List<Student> studentList) {
List<Student> response = (List<Student>) studentRepository.saveAll(studentList);
return response;
}
@Transactional
public List<Student> findByNameIsNull() {
List<Student> response = (List<Student>) studentRepository.findByNameIsNull();
return response;
}
@Transactional
public List<Student> findByNameOrNameIsNull(String name) {
List<Student> response = (List<Student>) studentRepository.findByNameOrNameIsNull(name);
return response;
}
@Transactional
public List<Student> findByNameAndUniversityOrNameIsNull(String name, String university) {
List<Student> response = (List<Student>) studentRepository.findByNameAndUniversityOrNameIsNull(name, university);
return response;
}
}
SpringMain.java
package com.javatute.main;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.autoconfigure.domain.EntityScan;
import org.springframework.context.annotation.ComponentScan;
@SpringBootApplication
@ComponentScan(basePackages = "com.*")
@EntityScan("com.javatute.entity")
public class SpringMain {
public static void main(String[] args) {
SpringApplication.run(SpringMain.class, args);
}
}
Note – See more details about @ComponentScan here.
JpaConfig.java
package com.javatute.config;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.jpa.repository.config.EnableJpaRepositories;
@Configuration
@EnableJpaRepositories(basePackages = "com.javatute.repository")
public class JpaConfig {
}
Note – See more details about @Configuration annotations here.
application.properties
# Connection url for the database spring.datasource.url=jdbc:oracle:thin:@localhost:1521:XE spring.datasource.username=SYSTEM spring.datasource.password=oracle2 spring.datasource.driver-class-name=oracle.jdbc.driver.OracleDriver # Show or not log for each sql query spring.jpa.show-sql = true spring.jpa.hibernate.ddl-auto =create spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.Oracle10gDialect server.port = 9091
Let’s run the SpringMain class(run as java application).
Perform saveall operation first using below REST API.
Request Data.
[
{
"name": "john",
"rollNumber": "0126CS01",
"university":"rgtu"
},
{
"name": null,
"rollNumber": "0126CS02",
"university":"rgtu"
},
{
"name": "aric",
"rollNumber": "0126CS03",
"university":"rgtu"
},
{
"name": null,
"rollNumber": "0126CS04",
"university":"rgtu"
}
]
Response data –
[
{
"id": 1,
"name": "john",
"rollNumber": "0126CS01",
"university": "rgtu"
},
{
"id": 2,
"name": null,
"rollNumber": "0126CS02",
"university": "rgtu"
},
{
"id": 3,
"name": "aric",
"rollNumber": "0126CS03",
"university": "rgtu"
},
{
"id": 4,
"name": null,
"rollNumber": "0126CS04",
"university": "rgtu"
}
]
Test the below URLs.
localhost:9091/student/findbynameornameisnull/john
localhost:9091/student/findbynameanduniversityornameisnull/{name}/{rgtu}
That’s all about Spring Data JPA IsNull Example Using Spring Boot and Oracle.
You may like.
- Spring Data JPA CrudRepository findById()
- Spring Data findById() Vs getOne()
- Spring Data JPA JpaRepository getOne()
- Spring Data CrudRepository saveAll() and findAll().
- Spring Data CrudRepository existsById()
- Spring Data JPA delete() vs deleteInBatch()
- Spring Data JPA deleteAll() Vs deleteAllInBatch()
- Spring Data JPA JpaRepository deleteAllInBatch()
- Spring Data JPA deleteInBatch() Example
- Spring Data JPA JpaRepository saveAndFlush() Example
- Spring Data JPA CrudRepository count() Example
- Spring Data JPA CrudRepository delete() and deleteAll()
- Spring Data JPA CrudRepository deleteById() Example
- CrudRepository findAllById() Example Using Spring Boot
- Spring Data CrudRepository save() Method.
- Sorting in Spring Data JPA using Spring Boot.
- Spring Data JPA example using spring boot.
- Spring Data JPA and its benefit.
Other Spring Data JPA and Hibernate tutorials.
- @Version Annotation Example In Hibernate.
- Hibernate Validator Constraints Example Using Spring Boot.
- @Temporal Annotation Example In Hibernate/Jpa Using Spring Boot.
- Hibernate Table Per Concrete Class Spring Boot.
- Hibernate Table Per Subclass Inheritance Spring Boot.
- Hibernate Single Table Inheritance using Spring Boot.
- One To One Mapping Annotation Example in Hibernate/JPA using Spring Boot and Oracle.
- One To One Bidirectional Mapping Example In Hibernate/JPA Using Spring Boot and Oracle.
- One To Many Mapping Annotation Example In Hibernate/JPA Using Spring Boot And Oracle.
- Many To One Unidirectional Mapping In Hibernate/JPA Annotation Example Using Spring Boot and Oracle.
- One To Many Bidirectional Mapping In Hibernate/JPA Annotation Example Using Spring Boot and Oracle.
- Many To Many Mapping Annotation Example In Hibernate/JPA Using Spring Boot And
Spring Data JPA Docs.
Summary – We have seen about Spring Data JPA IsNull Example. We Covered below Query Methods.
public List<Student> findByNameIsNull();
public List<Student> findByNameOrNameIsNull(String name);
public List<Student> findByNameAndUniversityOrNameIsNull(String name, String university);
