Problem
Assume I have an Employee POJO:
package com.example.demo.vo;
import com.example.demo.enumeration.Gender;
import com.example.demo.enumeration.YesOrNoType;
import lombok.Data;
import lombok.ToString;
@Data
@ToString
public class Employee {
/**
* 員工編號
*/
private Integer id;
/**
* 員工姓名
*/
private String name;
/**
* 員工性別
*/
private Gender gender;
/**
* 是否離職
*/
private YesOrNoType quit;
}
and an EmployeeDto POJO:
package com.example.demo.vo;
import lombok.Data;
@Data
public class EmployeeDto {
/**
* 員工編號
*/
private String id;
/**
* 員工姓名
*/
private String name;
/**
* 員工性別
*/
private String gender;
/**
* 是否離職
*/
private String quit;
}
Gender Enumeration:
package com.example.demo.enumeration;
public enum Gender {
MALE("M", "男"), FEMALE("F", "女");
private final String value;
private final String description;
Gender(String value, String description) {
this.value = value;
this.description = description;
}
public String getValue() {
return value;
}
public String getDescription() {
return description;
}
}
YesOrNoType Enumeration:
package com.example.demo.enumeration;
public enum YesOrNoType {
YES("Y", "是"), NO("N", "否");
private final String value;
private final String description;
YesOrNoType(String value, String description) {
this.value = value;
this.description = description;
}
public String getValue() {
return value;
}
public String getDescription() {
return description;
}
}
If I would like to convert Employee to EmployeeDTO, and convert gender and quit attributes to description, how to do it?
How-To
Add the following configurations in your pom.xml
<properties>
<org.mapstruct.version>1.2.0.Final</org.mapstruct.version>
</properties>
<dependencies>
<dependency>
<groupId>org.mapstruct</groupId>
<artifactId>mapstruct</artifactId> <!-- use mapstruct-jdk8 for Java 8 or higher -->
<version>${org.mapstruct.version}</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.5.1</version>
<configuration>
<source>1.8</source> <!-- or higher, depending on your project -->
<target>1.8</target> <!-- or higher, depending on your project -->
<annotationProcessorPaths>
<path>
<groupId>org.mapstruct</groupId>
<artifactId>mapstruct-processor</artifactId>
<version>${org.mapstruct.version}</version>
</path>
</annotationProcessorPaths>
</configuration>
</plugin>
</plugins>
</build>
Create an EmployeeMapper:
package com.example.demo.mapStruct;
import org.mapstruct.DecoratedWith;
import org.mapstruct.Mapper;
import com.example.demo.vo.Employee;
import com.example.demo.vo.EmployeeDto;
@Mapper
@DecoratedWith(EmployeeDecorator.class)
public interface EmployeeMapper {
EmployeeDto toDto(Employee employee);
}
Create an EmployeeDecorator:
package com.example.demo.mapStruct;
import com.example.demo.vo.Employee;
import com.example.demo.vo.EmployeeDto;
public class EmployeeDecorator implements EmployeeMapper {
private EmployeeMapper delegate;
public EmployeeDecorator(EmployeeMapper delegate) {
super();
this.delegate = delegate;
}
@Override
public EmployeeDto toDto(Employee employee) {
EmployeeDto dto = delegate.toDto(employee);
dto.setId(employee.getId().toString());
dto.setGender(employee.getGender().getDescription());
dto.setQuit(employee.getQuit().getDescription());
return dto;
}
}
Create a test class:
package com.example.demo;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import org.mapstruct.factory.Mappers;
import com.example.demo.enumeration.Gender;
import com.example.demo.enumeration.YesOrNoType;
import com.example.demo.mapStruct.EmployeeMapper;
import com.example.demo.vo.Employee;
import com.example.demo.vo.EmployeeDto;
import lombok.extern.slf4j.Slf4j;
@Slf4j
public class MapStructTest {
private static List<Employee> employees = new ArrayList<>();
static {
Employee albert = new Employee();
albert.setId(1);
albert.setName("Albert");
albert.setGender(Gender.MALE);
albert.setQuit(YesOrNoType.NO);
Employee mandy = new Employee();
mandy.setId(2);
mandy.setName("Mandy");
mandy.setGender(Gender.FEMALE);
mandy.setQuit(YesOrNoType.NO);
Employee peter = new Employee();
peter.setId(3);
peter.setName("Peter");
peter.setGender(Gender.MALE);
peter.setQuit(YesOrNoType.YES);
employees = Arrays.asList(albert, mandy, peter);
}
public static void main(String[] args) {
EmployeeMapper mapper = Mappers.getMapper(EmployeeMapper.class);
for (Employee employee : employees) {
EmployeeDto dto = mapper.toDto(employee);
log.debug("employee: " + employee.toString() + ", dto : " + dto.toString());
}
}
}
10:51:10.018 [main] DEBUG com.example.demo.MapStructTest - employee: Employee(id=1, name=Albert, gender=MALE, quit=NO), dto : EmployeeDto(id=1, name=Albert, gender=男, quit=否)
10:51:10.020 [main] DEBUG com.example.demo.MapStructTest - employee: Employee(id=1, name=Mandy, gender=FEMALE, quit=NO), dto : EmployeeDto(id=2, name=Mandy, gender=女, quit=否)
10:51:10.020 [main] DEBUG com.example.demo.MapStructTest - employee: Employee(id=3, name=Peter, gender=MALE, quit=YES), dto : EmployeeDto(id=3, name=Peter, gender=男, quit=是)
