Global Exception Handling

GlobalExceptionHandling/pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.7.2</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>com.gloabalexceptionhandling</groupId>
+	<artifactId>demo</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>GlobalExceptionHandling</name>
+	<description>Global Exception Handling in Spring Boot </description>
+	<properties>
+		<java.version>1.8</java.version>
+	</properties>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-data-jpa</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-devtools</artifactId>
+			<scope>runtime</scope>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>mysql</groupId>
+			<artifactId>mysql-connector-java</artifactId>
+			<scope>runtime</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.projectlombok</groupId>
+			<artifactId>lombok</artifactId>
+			<optional>true</optional>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+				<configuration>
+					<excludes>
+						<exclude>
+							<groupId>org.projectlombok</groupId>
+							<artifactId>lombok</artifactId>
+						</exclude>
+					</excludes>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

GlobalExceptionHandling/src/main/java/com/gloabalexceptionhandling/Controller/StudentController.java

+package com.gloabalexceptionhandling.Controller;
+
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.*;
+import com.gloabalexceptionhandling.Model.Student;
+import org.springframework.beans.factory.annotation.Autowired;
+import com.gloabalexceptionhandling.Service.StudentServiceImpl;
+
+import java.util.List;
+
+import static org.springframework.http.HttpStatus.CREATED;
+import static org.springframework.http.HttpStatus.OK;
+
+@RestController
+public class StudentController {
+
+    @Autowired
+    private StudentServiceImpl studentService;
+
+    @GetMapping("/students")
+    public List<Student> getAllStudents() {
+        return this.studentService.getAllStudents();
+    }
+
+    @GetMapping("/students/{id}")
+    public ResponseEntity<?> getStudentByID(@PathVariable("id") int id) {
+        Student getStudent = studentService.getStudentByID(id);
+        return  new ResponseEntity<Student>(getStudent, OK);
+    }
+
+    @PostMapping("/students")
+    public ResponseEntity<?>  addStudent(@RequestBody Student student) {
+        Student st = this.studentService.addStudent(student);
+        return new ResponseEntity<Student>(st, CREATED);
+    }
+
+    @PutMapping("/students/{studentId}")
+    public Student updateStudent(@RequestBody Student student, @PathVariable("studentId")int studentId) {
+        this.studentService.updateStudent(student, studentId);
+        return student;
+    }
+
+    @DeleteMapping("/students/{studentId}")
+    public void deleteStudent(@PathVariable("studentId") int studentId) {
+        this.studentService.deleteStudentById(studentId);
+    }
+
+}
\ No newline at end of file

GlobalExceptionHandling/src/main/java/com/gloabalexceptionhandling/Exception/ArrayResponseDto.java

+package com.gloabalexceptionhandling.Exception;
+
+import lombok.*;
+
+@Getter
+@Setter
+@ToString
+@NoArgsConstructor@AllArgsConstructor
+public class ArrayResponseDto {
+
+    private String date;
+    private String errorMessage;
+
+}

GlobalExceptionHandling/src/main/java/com/gloabalexceptionhandling/Exception/EmptyInputException.java

+package com.gloabalexceptionhandling.Exception;
+
+import org.springframework.stereotype.Component;
+
+@Component
+public class EmptyInputException extends  RuntimeException {
+
+    private String errorCode;
+    private String errorMessage;
+
+    private static final long serialVersionUID = 1L;
+
+    public String getErrorCode(){
+        return errorCode;
+    }
+
+    public void setErrorCode(String errorCode) {
+        this.errorCode = errorCode;
+    }
+
+    public String getErrorMessage() {
+        return errorMessage;
+    }
+
+    public void setErrorMessage(String errorMessage) {
+        this.errorMessage = errorMessage;
+    }
+
+    public static long getSerialVersionUID() {
+        return serialVersionUID;
+    }
+    public EmptyInputException(String errorCode, String errorMessage){
+        super();
+        this.errorCode = errorCode;
+        this.errorMessage = errorMessage;
+    }
+    public EmptyInputException(){
+
+    }
+}

GlobalExceptionHandling/src/main/java/com/gloabalexceptionhandling/Exception/NoSuchElementException.java

+package com.gloabalexceptionhandling.Exception;
+
+public class NoSuchElementException extends RuntimeException{
+
+    private String errorCode;
+    private String errorMessage;
+
+    private static final long serialVersionUID = 1L;
+
+    public String getErrorCode(){
+        return errorCode;
+    }
+
+    public void setErrorCode(String errorCode) {
+        this.errorCode = errorCode;
+    }
+
+    public String getErrorMessage() {
+        return errorMessage;
+    }
+
+    public void setErrorMessage(String errorMessage) {
+        this.errorMessage = errorMessage;
+    }
+
+    public static long getSerialVersionUID() {
+        return serialVersionUID;
+    }
+
+    public NoSuchElementException(String errorCode, String errorMessage){
+        super();
+        this.errorCode = errorCode;
+        this.errorMessage = errorMessage;
+    }
+
+    public NoSuchElementException(){
+
+    }
+
+
+
+}

GlobalExceptionHandling/src/main/java/com/gloabalexceptionhandling/GlobalExceptionHandlingApplication.java

+package com.gloabalexceptionhandling;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class GlobalExceptionHandlingApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(GlobalExceptionHandlingApplication.class, args);
+		System.out.println("Project Started..............");
+
+	}
+
+}

GlobalExceptionHandling/src/main/java/com/gloabalexceptionhandling/Handler/ControllerAdvice.java

+package com.gloabalexceptionhandling.Handler;
+
+import java.util.NoSuchElementException;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.ExceptionHandler;
+import com.gloabalexceptionhandling.Exception.ArrayResponseDto;
+import com.gloabalexceptionhandling.Exception.EmptyInputException;
+import org.springframework.web.servlet.mvc.method.annotation.ResponseEntityExceptionHandler;
+
+@org.springframework.web.bind.annotation.ControllerAdvice
+public class ControllerAdvice extends  ResponseEntityExceptionHandler {
+
+    @ExceptionHandler(EmptyInputException.class)
+    public ResponseEntity<String> handleEmptyInput(EmptyInputException  emptyInputException){
+        return  new ResponseEntity("Sorry Your Fields Are Empty  Please Check Fields ...........!! " ,  HttpStatus.BAD_REQUEST);
+    }
+
+    @ExceptionHandler (NullPointerException.class)
+    public ResponseEntity<?> handleNullPointerException(NullPointerException nullPointerException){
+        ArrayResponseDto arrayResponseDto = new ArrayResponseDto("02/08/2022", "There Is No Student Available Belongs to This ID");
+        return new ResponseEntity(arrayResponseDto, HttpStatus.OK);
+    }
+
+    @ExceptionHandler (NoSuchElementException.class)
+ public ResponseEntity<String> handleNoSuchElementException(NoSuchElementException noSuchElementException){
+        return new ResponseEntity<String>("There Is No Value Present For This Id ", HttpStatus.NOT_FOUND);
+ }
+
+    }

GlobalExceptionHandling/src/main/java/com/gloabalexceptionhandling/Model/Student.java

+package com.gloabalexceptionhandling.Model;
+
+import lombok.*;
+
+import javax.persistence.*;
+
+@Getter
+@Setter
+@ToString
+@NoArgsConstructor
+@AllArgsConstructor
+@Entity
+@Table(name = "studentHandling")
+public class Student {
+    @Id
+    @GeneratedValue(strategy = GenerationType.IDENTITY)
+    private int id;
+    private String name;
+    private String degree;
+    private String university;
+
+}

GlobalExceptionHandling/src/main/java/com/gloabalexceptionhandling/Repository/StudentRepository.java

+package com.gloabalexceptionhandling.Repository;
+
+import com.gloabalexceptionhandling.Model.Student;
+import org.springframework.data.repository.CrudRepository;
+import org.springframework.stereotype.Repository;
+
+@Repository
+public interface StudentRepository extends CrudRepository<Student, Integer> {
+
+    Student findById(int id);
+
+
+}

GlobalExceptionHandling/src/main/java/com/gloabalexceptionhandling/Service/StudentService.java

+package com.gloabalexceptionhandling.Service;
+
+import java.util.List;
+import com.gloabalexceptionhandling.Model.Student;
+
+public interface StudentService {
+
+    //Get All Students
+    public List<Student> getAllStudents();
+
+    // Students get by id
+    public Student getStudentByID(int id);
+
+    // Add student records
+    public Student addStudent(Student st);
+
+    //Delete by id
+    void deleteStudentById(int sid);
+
+    // Update records
+    public void updateStudent(Student sstudent, int studentId);
+
+
+}

GlobalExceptionHandling/src/main/java/com/gloabalexceptionhandling/Service/StudentServiceImpl.java

+package com.gloabalexceptionhandling.Service;
+
+import java.util.List;
+import java.util.NoSuchElementException;
+import org.springframework.stereotype.Service;
+import com.gloabalexceptionhandling.Model.Student;
+import org.springframework.beans.factory.annotation.Autowired;
+import com.gloabalexceptionhandling.Repository.StudentRepository;
+import com.gloabalexceptionhandling.Exception.EmptyInputException;
+
+@Service
+public class StudentServiceImpl implements StudentService{
+
+    @Autowired
+    private StudentRepository studentRepository;
+
+    @Override
+    public List<Student> getAllStudents() {
+        List<Student> list = (List<Student>) studentRepository.findAll();
+        if (list.isEmpty())
+            throw new EmptyInputException("604", "Hey List is Completely Empty ......!!");
+        return list;
+    }
+
+    @Override
+    public Student getStudentByID(int id) {
+        Student student=  studentRepository.findById(id);
+        if (student.getName().length()==0)
+            throw new NoSuchElementException("There Is No Student Available for this id ");
+        return student;
+    }
+
+    @Override
+    public Student addStudent(Student st) {
+       if (st.getName().isEmpty() || st.getName().length()==0){
+           throw new EmptyInputException("601", "Input Field Are Empty....!!");
+       }
+       Student savestudent = studentRepository.save(st);
+       return savestudent;
+    }
+
+    @Override
+    public void deleteStudentById(int sid) {
+    studentRepository.deleteById(sid);
+    }
+
+
+    @Override
+    public void updateStudent(Student student, int studentId) {
+        student.setId(studentId);
+        studentRepository.save(student);
+    }
+
+}
\ No newline at end of file

GlobalExceptionHandling/src/main/resources/application.properties

+server.port=8081
+spring.datasource.name=firstDBPractice
+spring.datasource.url=jdbc:mysql://localhost:3306/firstDBPractice?characterEncoding=utf8
+spring.datasource.username= root
+spring.datasource.password=nisum123
+spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
+spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.MySQL55Dialect
+spring.jpa.generate-ddl=true
+spring.jpa.hibernate.ddl-auto=update

GlobalExceptionHandling/src/test/java/com/gloabalexceptionhandling/GlobalExceptionHandlingApplicationTests.java

+package com.gloabalexceptionhandling;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class GlobalExceptionHandlingApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}