Convert Date to Number and Number to Date in Oracle

How we can convert date to number in oracle

select to_number(to_char(add_months(sysdate,-0),'yyyymm')) from dual;

How we can convert number to date

select to_char(to_date(202007,'yyyymm'),'dd-mon-yyyy') from dual;

Spring Boot with Swagger UI , JPA , MYSQL , Mockito, Integration Test and Sonar Qube

This post will expain you about
1. How we will integrate spring boot and swagger api
2. Spring boot with JPA and MySQL (Crud Repository and NamedJdbcTemplate)
3 Spring mockMvc test for controller
4. Integration test for Service and DAO classes
5. Usage of Mockito
6. Sonarqube Code coverage

Step 1 : create a maven project called - springboot-jpa-swagger-mysql-sonarqube in eclipse
Step 2 : provide groupId,artifactId,version,jar,name and description
Step 3: Replace below pom.xml into your local system
pom.xml will have dependencies related to spring boot,swagger,jdbc,mysql,mockito,sonarqube

 4.0.0

 com.siva.springboot.javaguruonline
 springboot-jpa-swagger-mysql-sonarqube
 0.0.1-SNAPSHOT
 jar

 springboot-jpa-swagger-mysql-sonarqube
 Demo project for Spring Boot PJA MySQL AND Sonarqube

 
  org.springframework.boot
  spring-boot-starter-parent
  2.0.5.RELEASE
  
 

 
  UTF-8
  UTF-8
  1.8
 

 
  
   org.springframework.boot
   spring-boot-starter-data-jpa
  
  
   org.springframework.boot
   spring-boot-starter-web
  

  
   org.springframework.boot
   spring-boot-starter-test
   test
  

  
   mysql
   mysql-connector-java
   runtime
  
  
  
   io.springfox
   springfox-swagger2
   2.8.0
  
  
   io.springfox
   springfox-swagger-ui
   2.8.0
  
  
   io.springfox
   springfox-bean-validators
   2.8.0
  
  
   javax.xml
   jaxb-api
   2.1
  
  
   org.projectlombok
   lombok
   1.18.12
   provided
  

  
  
   org.sonarsource.scanner.maven
   sonar-maven-plugin
   3.0.2
  
 

 
  
   
    org.springframework.boot
    spring-boot-maven-plugin
   
   
    org.codehaus.mojo
    sonar-maven-plugin
    3.0.2
   
   
    org.jacoco
    jacoco-maven-plugin
    0.8.0
    
     
      default-prepare-agent
      
       prepare-agent
      
     
     
      default-report
      prepare-package
      
       report
      
     
    
   
  
 

Step 4: Now create a Springboot application, which is the starting point to run the Application.

Step 5: create appliaction.properties under resources folder, add the db related details

## Spring DATASOURCE (DataSourceAutoConfiguration & DataSourceProperties)
spring.datasource.url = jdbc:mysql://localhost:3306/employee
spring.datasource.username = root
spring.datasource.password = root


## Hibernate Properties
# The SQL dialect makes Hibernate generate better SQL for the chosen database
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL5InnoDBDialect

# Hibernate ddl auto (create, create-drop, validate, update)
spring.jpa.hibernate.ddl-auto = update

logging.level.root = DEBUG

spring.main.banner-mode=off
spring.datasource.platform=h2

Step 5: Create a SwaggerConfig class, which will have the details , what is controller package and other details
Learn more about Swagger API swagger-ui

package com.siva.springboot.javaguruonline.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import springfox.documentation.builders.ApiInfoBuilder;
import springfox.documentation.builders.PathSelectors;
import springfox.documentation.builders.RequestHandlerSelectors;
import springfox.documentation.service.ApiInfo;
import springfox.documentation.service.Contact;
import springfox.documentation.spi.DocumentationType;
import springfox.documentation.spring.web.plugins.Docket;
import springfox.documentation.swagger2.annotations.EnableSwagger2;

@Configuration
@EnableSwagger2
public class Swagger2Config {
 @Bean
 public Docket api() {
  return new Docket(DocumentationType.SWAGGER_2).select()
    .apis(RequestHandlerSelectors
      .basePackage("com.siva.springboot.javaguruonline.controller"))
    .paths(PathSelectors.regex("/.*"))
    .build().apiInfo(apiEndPointsInfo());
 }

 private ApiInfo apiEndPointsInfo() {

  return new ApiInfoBuilder().title("Spring Boot REST API")
    .description("Employee Management REST API")
    .contact(new Contact("Siva Raju", "http://www.javaguruonline.com", "siva82k@gmail.com"))
    .license("Apache 2.0")
    .licenseUrl("http://www.apache.org/licenses/LICENSE-2.0.html")
    .version("1.0.0")
    .build();
 }
}

Step 6 : This project is related to employee management system - like Employee CRUD operations

Step 7 : Write Model class called Employee and EmployeeDetails

package com.siva.springboot.javaguruonline.model;

import java.io.Serializable;

import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;

import io.swagger.annotations.ApiModel;
import io.swagger.annotations.ApiModelProperty;
import lombok.EqualsAndHashCode;
import lombok.ToString;

@Entity
@Table(name = "employee")
@ApiModel(description="All details about the Employee. ")
@ToString
@EqualsAndHashCode
public class Employee implements Serializable{

 /**
  * 
  */
 private static final long serialVersionUID = 7407317371057056536L;

 @ApiModelProperty(notes = "The database generated employee ID")
 private int id;

 @ApiModelProperty(notes = "The employee name")
 private String name;

 @ApiModelProperty(notes = "The employee age")
 private int age;

 public Employee() {

 }

 public Employee(String name, int age) {
  this.name = name;
  this.age = age;
 }

 @Id
 @GeneratedValue(strategy = GenerationType.AUTO)
 @Column(name = "emp_id", nullable = false)
 public int getId() {
  return id;
 }

 public void setId(int id) {
  this.id = id;
 }

 @Column(name = "emp_name", nullable = false)
 public String getName() {
  return name;
 }

 public void setName(String name) {
  this.name = name;
 }
 @Column(name = "email_age", nullable = false)
 public int getAge() {
  return age;
 }

 public void setAge(int age) {
  this.age = age;
 }

}

package com.siva.springboot.javaguruonline.model;

import lombok.EqualsAndHashCode;
import lombok.ToString;

@ToString
@EqualsAndHashCode
public class EmployeeDetails {
 
 private int empId;
 public int getEmpId() {
  return empId;
 }
 public void setEmpId(int empId) {
  this.empId = empId;
 }
 public String getEmpName() {
  return empName;
 }
 public void setEmpName(String empName) {
  this.empName = empName;
 }
 private String empName;

}

Step 8: Step 8: service/serviceimpl and repository classes

In the repository class, It is extending the JpaRepository, which will get all the default methods related to that Model Object.
In the DAO class, NamedParameterJdbcTemplate , to work with native query and how to map using rowmapper

package com.siva.springboot.javaguruonline.repository;

import java.util.List;

import com.siva.springboot.javaguruonline.model.EmployeeDetails;

public interface EmployeeDao {
 
 public List getEmployeeDetails();
 

}

package com.siva.springboot.javaguruonline.repository;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate;
import org.springframework.stereotype.Repository;

import com.siva.springboot.javaguruonline.mapper.EmployeeDetailsMapper;
import com.siva.springboot.javaguruonline.model.EmployeeDetails;

@Repository
public class EmployeeDaoImpl implements EmployeeDao{
 String sqlQuery="select emp_id,emp_name from employee";
 @Autowired
 private NamedParameterJdbcTemplate namedParameterJdbcTemplate;

 @Override
 public List getEmployeeDetails() {
  return namedParameterJdbcTemplate.query(sqlQuery, new EmployeeDetailsMapper());
 }

}

package com.siva.springboot.javaguruonline.mapper;

import java.sql.ResultSet;
import java.sql.SQLException;

import org.springframework.jdbc.core.RowMapper;

import com.siva.springboot.javaguruonline.model.EmployeeDetails;

public class EmployeeDetailsMapper implements RowMapper {
 @Override
 public EmployeeDetails mapRow(ResultSet resultset, int count) throws SQLException {
  EmployeeDetails employeeDetails = new EmployeeDetails();
  employeeDetails.setEmpId(resultset.getInt("emp_id"));
  employeeDetails.setEmpName(resultset.getString("emp_name"));
  return employeeDetails;
 }
 

}

package com.siva.springboot.javaguruonline.repository;

import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

import com.siva.springboot.javaguruonline.model.Employee;

@Repository
public interface EmployeeRepository extends JpaRepository{

}

Step 9: Write Controller class, which will have the all the crud operations

package com.siva.springboot.javaguruonline.controller;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

import javax.validation.Valid;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.DeleteMapping;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.PutMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import com.siva.springboot.javaguruonline.exception.ResourceNotFoundException;
import com.siva.springboot.javaguruonline.model.Employee;
import com.siva.springboot.javaguruonline.model.EmployeeDetails;
import com.siva.springboot.javaguruonline.repository.EmployeeDao;
import com.siva.springboot.javaguruonline.repository.EmployeeRepository;

import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import io.swagger.annotations.ApiParam;
import io.swagger.annotations.ApiResponse;
import io.swagger.annotations.ApiResponses;


@RestController
@RequestMapping("/api/v1")
@Api(value="Employee Management System")
public class EmployeeController {
 private static final String EMPLOYEE_NOT_FOUND_FOR_THIS_ID = "Employee not found for this id :: ";

 @Autowired
 private EmployeeRepository employeeRepository;
 
 @Autowired
 private EmployeeDao employeeDao;

 @ApiOperation(value = "View a list of available employees", response = List.class)
 @ApiResponses(value = { @ApiResponse(code = 200, message = "Successfully retrieved list"),
   @ApiResponse(code = 401, message = "You are not authorized to view the resource"),
   @ApiResponse(code = 403, message = "Accessing the resource you were trying to reach is forbidden"),
   @ApiResponse(code = 404, message = "The resource you were trying to reach is not found") })
 @GetMapping("/employees")
 public List getAllEmployees() {
  return employeeRepository.findAll();
 }
 
 @ApiOperation(value = "View a list of available employee details", response = List.class)
 @ApiResponses(value = { @ApiResponse(code = 200, message = "Successfully retrieved list"),
   @ApiResponse(code = 401, message = "You are not authorized to view the resource"),
   @ApiResponse(code = 403, message = "Accessing the resource you were trying to reach is forbidden"),
   @ApiResponse(code = 404, message = "The resource you were trying to reach is not found") })
 @GetMapping("/employeedetails")
 public List getAllEmployeeDetails() {
  return employeeDao.getEmployeeDetails();
 }

 @ApiOperation(value = "Get an employee by Id")
 @GetMapping("/employees/{id}")
 public ResponseEntity getEmployeeById(
   @ApiParam(value = "Employee id from which employee object will retrieve", required = true)
   @PathVariable(value = "id") Long employeeId)
   throws ResourceNotFoundException {
  Employee employee = employeeRepository.findById(employeeId)
    .orElseThrow(() -> new ResourceNotFoundException(EMPLOYEE_NOT_FOUND_FOR_THIS_ID + employeeId));
  return ResponseEntity.ok().body(employee);
 }

 @ApiOperation(value = "Add an employee")
 @PostMapping("/employees")
 public Employee createEmployee(
   @ApiParam(value = "Employee object store in database table", required = true)
   @Valid @RequestBody Employee employee) {
  return employeeRepository.save(employee);
 }

 @ApiOperation(value = "Update an employee")
 @PutMapping("/employees/{id}")
 public ResponseEntity updateEmployee(
   @ApiParam(value = "Employee Id to update employee object", required = true)
   @PathVariable(value = "id") Long employeeId,
   @ApiParam(value = "Update employee object", required = true)
   @Valid @RequestBody Employee employeeDetails) throws ResourceNotFoundException {
  Employee employee = employeeRepository.findById(employeeId)
    .orElseThrow(() -> new ResourceNotFoundException(EMPLOYEE_NOT_FOUND_FOR_THIS_ID + employeeId));

  employee.setName(employeeDetails.getName());
  employee.setAge(employeeDetails.getAge());
  final Employee updatedEmployee = employeeRepository.save(employee);
  return ResponseEntity.ok(updatedEmployee);
 }

 @ApiOperation(value = "Delete an employee")
 @DeleteMapping("/employees/{id}")
 public Map deleteEmployee(
   @ApiParam(value = "Employee Id from which employee object will delete from database table", required = true)
   @PathVariable(value = "id") Long employeeId)
   throws ResourceNotFoundException {
  Employee employee = employeeRepository.findById(employeeId)
    .orElseThrow(() -> new ResourceNotFoundException(EMPLOYEE_NOT_FOUND_FOR_THIS_ID + employeeId));

  employeeRepository.delete(employee);
  Map response = new HashMap<>();
  response.put("deleted", Boolean.TRUE);
  return response;
 }
}

Step 10: Once above code has been completed, then you can run the application by right clicking on the Springboot application.
Step 11. Once the application executed successfully, then we need to test this application

One way is either Using- SOAP UI, Postman - these needs to be installed on our machine, else we can't test the rest service.
To test the REST API, we already configured Swagger UI. So just go to your web browser, then click, http://localhost:8080/swagger-ui.html - it will display all the operations, which is availabe in controller class.


Now you can test those API's by giving request parameters



Step 12: Once done, we need to write Junit test cases for the all the classes

package com.siva.springboot.javaguruonline;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest
public class SpringbootJpaSwaggerSonarqubeApplicationTest {

 @Test
 public void contextLoads() {
 }

}

Controller class test

package com.siva.springboot.javaguruonline.controller;

import static org.hamcrest.Matchers.hasSize;
import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.jsonPath;
import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;

import java.io.File;
import java.io.FileWriter;
import java.util.ArrayList;
import java.util.List;

import javax.annotation.meta.When;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.mockito.Mock;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.http.MediaType;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.web.servlet.MockMvc;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.siva.springboot.javaguruonline.SpringbootJpaSwaggerSonarqubeApplication;
import com.siva.springboot.javaguruonline.model.Employee;
import com.siva.springboot.javaguruonline.model.EmployeeDetails;
import com.siva.springboot.javaguruonline.repository.EmployeeDaoImpl;
import com.siva.springboot.javaguruonline.repository.EmployeeRepository;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.when;

@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest(webEnvironment = SpringBootTest.WebEnvironment.RANDOM_PORT,classes=SpringbootJpaSwaggerSonarqubeApplication.class)
@AutoConfigureMockMvc
public class EmployeeControllerTest {
 @Autowired
 private MockMvc mockMvc;
 
 @Autowired
 private EmployeeRepository employeeRepository;
 @Mock
 private EmployeeDaoImpl employeeDao;
 
 
 @Test
 public void testGetAllEmployees() throws Exception{
  List employeeList  = employeeRepository.findAll();
  ObjectMapper mapper = new ObjectMapper();
  String jsonString = mapper.writeValueAsString(employeeList);
  FileWriter file = new FileWriter(new File("employee.json"));
  file.write(jsonString);
  file.close();
  this.mockMvc.perform(get("/api/v1/employees")).andExpect(status().isOk()).andExpect(content().contentType(MediaType.APPLICATION_JSON_UTF8))
  .andExpect(jsonPath("$", hasSize(4)));

 } 
 
 @Test
 public void testGetAllEmployeeDetails()  throws Exception {
  EmployeeDetails employee = new EmployeeDetails();
  employee.setEmpId(123);
  employee.setEmpName("Siva");
  List employeeList = new ArrayList();
  employeeList.add(employee);
  when(employeeDao.getEmployeeDetails()).thenReturn(employeeList);
  this.mockMvc.perform(get("/api/v1/employeedetails")).andExpect(status().isOk()).andExpect(content().contentType(MediaType.APPLICATION_JSON_UTF8))
  .andExpect(jsonPath("$", hasSize(4)));
  
 }

}

DaoImpl Test

package com.siva.springboot.javaguruonline.repository;

import java.util.List;

import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import com.siva.springboot.javaguruonline.SpringbootJpaSwaggerSonarqubeApplication;
import com.siva.springboot.javaguruonline.model.EmployeeDetails;
import com.siva.springboot.javaguruonline.repository.EmployeeDao;
@RunWith(SpringRunner.class)
@SpringBootTest(classes = SpringbootJpaSwaggerSonarqubeApplication.class)
public class EmployeeDaoImplTest {
 
 @Autowired
 public EmployeeDao employeeDao;
 
 @Test
 public void testGetAllEmployeeDetails(){
  List employeeDetails = employeeDao.getEmployeeDetails();
  Assert.assertNotNull(employeeDetails);
 }

}

Repository Test

package com.siva.springboot.javaguruonline.repository;

import java.util.List;

import org.junit.Assert;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

import com.siva.springboot.javaguruonline.SpringbootJpaSwaggerSonarqubeApplication;
import com.siva.springboot.javaguruonline.model.Employee;
import com.siva.springboot.javaguruonline.repository.EmployeeRepository;

@RunWith(SpringRunner.class)
@SpringBootTest(classes = SpringbootJpaSwaggerSonarqubeApplication.class)
public class EmployeeRepositoryTest {
 @Autowired
 EmployeeRepository employeeRepository;
 
 @Test
 public void getEmployeeDetails(){
  List employeeList = employeeRepository.findAll();
  Assert.assertNotNull("EmployeeListNotEmpty", employeeList);;
 }
 

}

Step 13: We need to check the code coverage tool called Sonarqube, required dependencies added in pom.xml

Step 14: Download Sonarqube from SonarQube - and look for Historical Downloads, then download , which ever the version you want to work on.


Step 15 : Unzip that file and go to bin folder- StartSonar.bat file

Step 16 : Once Sonar is up, then go to browser and try http://localhost:9000 , login with username -admin and password- admin

Step 17: Once Sonarqube is up and running, we need to run the code through either sonar scanner or maven

Before Scanning the code, we need to create properties file called - sonar-project.properties place the inside of the your project
and need to mention src code path , test path, java version.. etc

# must be unique in a given SonarQube instance
sonar.projectKey=springboot-jpa-swagger-mysql-sonarqube
# this is the name displayed in the SonarQube UI
sonar.projectName=springboot-jpa-swagger-mysql-sonarqube
sonar.projectVersion=1.0


# Path is relative to the sonar-project.properties file. Replace "\" by "/" on Windows.
# Since SonarQube 4.2, this property is optional if sonar.modules is set. 
# If not set, SonarQube starts looking for source code from the directory containing 
# the sonar-project.properties file.
sonar.sources=/src/main/java/
 
# Encoding of the source code. Default is default system encoding
sonar.sourceEncoding=UTF-8

sonar.junit.reportPaths=./target/surefire-reports
# Generate sonar issues report in html and console
sonar.issuesReport.html.enable=true
sonar.issuesReport.console.enable=true

# Display Jacoco report into SonarQube dashboard
# Comma-separated paths to directories with tests (optional)
sonar.tests=/src/test/java/
# This name depends on the configuration in pom.xml. In this example we have ${project.build.directory}/coverage-reports/jacoco-ut.exec entry in our pom.xml
sonar.jacoco.reportPath=target/surefire-reports/jacoco-ut.exec
sonar.dynamicAnalysis=reuseReports
sonar.java.coveragePlugin=jacoco
sonar.jacoco.reportMissing.force.zero=true
sonar.java.binaries=/target/classes/
sonar.coverage.exclusions=**/*Employee.java,**/*EmployeeDetails.java,**/*ErrorDetails.java,**/*ErrorDetails.java,**/*ResourceNotFoundException.java

Step 18 : Use the below command to run the code coverage- make sure before running the sonar, sonarqube should up and running
Go to your project location in the command prompt.
/>mvn clean install sonar:sonar

Getting Started with Apache Solr on Windows

This Post will explain about what is Apache Solr and how to do the setup on windows environment, Basic Apache Solr commands

What is Apache Solr?

Solr is the popular, blazing-fast, open source enterprise search platform built on Apache Lucene

Solr is highly reliable, scalable and fault tolerant, providing distributed indexing, replication and load-balanced querying, automated failover and recovery, centralized configuration and more. Solr powers the search and navigation features of many of the world's largest internet sites

We need the Java Runtime Environment (JRE) version 1.8 or higher to install the Apache Solr

Check the java version using the below command

Java -version

Step 1:

Download the Apache latest version from this link, either source or binary
Download Apache Solr

Apache solr-8.4.1.zip


Step 2:

Unzip the downloaded one and set the path, inside environment variables, check my previous post how to set the environment variables

After Setting the env varibles, use the below command to start the solr


Step 3:

Go to the location, where it has unzipped up to bin folder

solr start

Will start the solr and give the message stating solr has been started

Know the status of the solr use the below command

solr status

create a core that uses a data-driven schema which tries to guess the correct field type when you add documents to the index.

solr create -c movies

Step 4:

Use the below link in the browser, to check about created core and other details

try with http://localhost:8983/


Step 5:

Stop the Solr

solr stop -all

Thank you for viewing this post , just we created the core, Next post will explain , how to do the indexing and search and many more features, which is provided by Apache Solr.

How Apache Kafka is Better than any other traditional messaging brokers(Active MQ,JMS,Camel,IBM MQ)

1. Kafka is a distributed streaming platform
2. Kafka stores all the messages before sending or after successufully received by subscriping applications.
3. Kafka Run as a cluster on one or more servers that can be available on multiple datacenters.
4. Kafka is client centric and it has fair distribution of related messages to consumers and it is extreamly fast and scalable broker
5. Kafka has Horizontally scalable, by adding more partitions
6. Kafka does not degrade performance , adding of new consumers
7. Kafaka uses one destination type called topic, which internally combines both publish-subscribe and point-to-point
8. Kafka message is key-value pair. payload of the message sent as the value.
9. Kafaka cients are responsible for replaying failed messages
10. Kafka retains messages, it is possible for clients to retrieve any message, providing option for re-processing of all messages.

Traditional messasing brokers either don't persist messages at all. and it will store only until they consumed and acknowledged.
Traditional messaging brokers like imperative programming, An event is occurred and our code is notified of that event. it is tightly coupled.

You can Read Apache Kafka for more information about apache kafka