MapStruct

MapStruct是用于生成类型安全的bean映射类的Java注解处理器，可以在model和实体类直接进行对象映射，通过注解的方式实现对javaBean的转换

1. 注解处理器；
2. 可以生成 JavaBean 之间那的映射代码；
3. 类型安全， 高性能， 无依赖性；

依赖

    org.mapstruct
    mapstruct-jdk8
    1.2.0.Final



    org.apache.maven.plugins
    maven-compiler-plugin
    3.5.1
    
        ${java.version}
        ${java.version}
        
            
                org.mapstruct
                mapstruct-processor
                1.2.0.Final
            
        
        
            
                -Amapstruct.suppressGeneratorTimestamp=true
            
            
                -Amapstruct.suppressGeneratorVersionInfoComment=true
            
        
    

Student.Class

import javax.persistence.*;

@Entity
@Table(name = "STUDENT")
public class Student {

    @Id
    @Column(name = "S_ID")
    private String sId;

    @Basic
    @Column(name = "S_NAME")
    private String sName;

    @Basic
    @Column(name = "S_SEX")
    private String sSex;

    public String getsId() {
        return sId;
    }

    public void setsId(String sId) {
        this.sId = sId;
    }

    public String getsName() {
        return sName;
    }

    public void setsName(String sName) {
        this.sName = sName;
    }

    public String getsSex() {
        return sSex;
    }

    public void setsSex(String sSex) {
        this.sSex = sSex;
    }

    @Override
    public String toString() {
        return "Student{" +
                "sId='" + sId + ''' +
                ", sName='" + sName + ''' +
                ", sSex='" + sSex + ''' +
                '}';
    }
}

Uesr.Class

public class Uesr {

    private String id;

    private String name;

    private String sex;

    public String getId() {
        return id;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getSex() {
        return sex;
    }

    public void setSex(String sex) {
        this.sex = sex;
    }
}

UesrMapper.Class

import org.mapstruct.Mapper;
import org.mapstruct.Mapping;
import org.mapstruct.Mappings;
import org.mapstruct.Named;
import org.mapstruct.factory.Mappers;

@Mapper
public interface UesrMapper {
    UesrMapper INSTANCE = Mappers.getMapper(UesrMapper.class);

    
    @Mappings({
            @Mapping(source = "id", target = "sId"),
            @Mapping(source = "name", target = "sName", qualifiedByName = "findByName"),
            @Mapping(source = "sex", target = "sSex")
    })
    Student userToStudent(Uesr uesr);

    @Named(value = "findByName")
    default String findByName(String name){
        if (name.equals("zs")){
            name = "张三";
        }
        return name;
    }
}

这里需要编译一下，点击maven中的package；会自动生成UesrMapper的实现类UesrMapperImpl；

@Generated(
    value = "org.mapstruct.ap.MappingProcessor"
)
public class UesrMapperImpl implements UesrMapper {

    @Override
    public Student userToStudent(Uesr uesr) {
        if ( uesr == null ) {
            return null;
        }

        Student student = new Student();

        student.setsSex( uesr.getSex() );
        student.setsName( findByName( uesr.getName() ) );
        student.setsId( uesr.getId() );

        return student;
    }
}

测试

import com.demo.sell.test.Student;
import com.demo.sell.test.Uesr;
import com.demo.sell.test.UesrMapper;
import org.junit.Test;

public class UesrTest {

   @Test
   public void Test(){
      Uesr uesr = new Uesr();
      uesr.setId("1");
      uesr.setName("zs");
      uesr.setSex("男");
      Student student = UesrMapper.INSTANCE.userToStudent(uesr);
      System.out.println(student);
   }
}

结果：Student{sId='1', sName='张三', sSex='男'}