exploding lists

Course.java

package test;

public class Course {
}

CourseDto.java

package test;

public class CourseDto {
}

CourseMapper.java

package test;

import java.util.List;

import org.mapstruct.Mapper;

@Mapper
public interface CourseMapper {

    CourseDto map( Course in );
    List<CourseDto> map( List<Course> in );

}

Program.java

package test;

public class Program {
}

ProgramDto.java

package test;

import java.util.List;

public class ProgramDto {

    private List<CourseDto> courses;

    public List<CourseDto> getCourses() {
        return courses;
    }

    public void setCourses(List<CourseDto> courses) {
        this.courses = courses;
    }
}

ProgramMapper.java

package test;

import org.mapstruct.Mapper;

@Mapper
public interface ProgramMapper {

    ProgramDto map( Program program );
}

Student.java

package test;

import java.util.List;

public class Student {

    private String name;
    private List<Course> courses;
    private List<Program> programs;

    public String getName() {
        return name;
    }

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

    public List<Course> getCourses() {
        return courses;
    }

    public void setCourses(List<Course> courses) {
        this.courses = courses;
    }

    public List<Program> getPrograms() {
        return programs;
    }

    public void setPrograms(List<Program> programs) {
        this.programs = programs;
    }
}

StudentDto.java

package test;

import java.util.List;

public class StudentDto {

    private String studentName;
    private List<ProgramDto> programs;

    public String getStudentName() {
        return studentName;
    }

    public void setStudentName(String studentName) {
        this.studentName = studentName;
    }

    public List<ProgramDto> getPrograms() {
        return programs;
    }

    public void setPrograms(List<ProgramDto> programs) {
        this.programs = programs;
    }
}

StudentMapper.java

package test;

import org.mapstruct.AfterMapping;
import org.mapstruct.Context;
import org.mapstruct.Mapper;
import org.mapstruct.Mapping;
import org.mapstruct.MappingTarget;

@Mapper( uses = ProgramMapper.class )
public interface StudentMapper {

    @Mapping( target = "studentName", source = "name" )
    @Mapping( target = "programs", source = "programs" ) // strictly not needed, same name
    StudentDto map( Student student, @Context CourseMapper courseMapper );

    @AfterMapping
    default void map(Student student, @MappingTarget StudentDto studentDto, @Context CourseMapper courseMapper) {

        for (ProgramDto programDto : studentDto.getPrograms() ) {
            programDto.setCourses( courseMapper.map( student.getCourses() ) );
        }
    }
}