Mapping 如何使用推土机将父字段映射到子对象字段

我正在使用推土机将我的对象A映射到B

Class A {
int indicatorA;
List<A> listA;
// get set methods...
}

Class B{
int indicatorB;
List<B> listB;
// get set methods...
}

映射之后，我希望看到像这样的对象B

B parentB//带指示符号B=10 和parentB.listB，其中有两个对象child1B和chld2B，indicatorB值设置为10

如何编写自定义转换器或任何简单的方法来做到这一点？ 非常感谢您的帮助。。

---

谢谢

是的，您需要一个CustomConverter实现，因为不能通过直接映射在列表的元素内设置值

推土机XML需要一个简单的配置标记，引用CustomConverter类：

<?xml version="1.0" encoding="UTF-8"?>
<mappings xmlns="http://dozer.sourceforge.net"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://dozer.sourceforge.net
          http://dozer.sourceforge.net/schema/beanmapping.xsd">
  <configuration>
    <custom-converters>
        <converter type="somepackage.MyConverter" >
            <class-a>somepackage.A</class-a>
            <class-b>somepackage.B</class-b>
        </converter>
    </custom-converters>     
  </configuration>
</mappings>

这是CustomConverter：

public class MyConverter implements CustomConverter {
    public Object convert(Object destination, Object source, Class destClass, Class sourceClass){
         if (source == null) {
              return null;
            }
            B dest = null;
            if (source instanceof A) {
                // check to see if the object already exists
                if (destination == null) {
                  dest = new B();
                } else {
                  dest = (B) destination;
                }

              //dest is your parentB instance

              //setting indicatorB value in parentB
                dest.setIndicatorB(((A) source).getIndicatorA()); 

              //creating child instances of B
                B child1B = new B();
                B child2B = new B();  

              //setting indicatorB values to the child instances as well
                child1B.setIndicatorB(((A) source).getIndicatorA());                
                child2B.setIndicatorB(((A) source).getIndicatorA()); 

              //adding child Bs to parentB list
                List<B> listOfBs = new ArrayList<B>(); 
                listOfBs.add(child1B);
                listOfBs.add(child2B);
                dest.setListB(listOfBs);
                return dest;
            }
            return null;        
    }
}

---

如果只有在运行时才知道childa的数量，则可以使用CustomConverter中的循环来创建相应数量的childb。

是的，您需要一个CustomConverter实现，因为不能通过直接映射在列表的元素内设置值

推土机XML需要一个简单的配置标记，引用CustomConverter类：

<?xml version="1.0" encoding="UTF-8"?>
<mappings xmlns="http://dozer.sourceforge.net"
          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://dozer.sourceforge.net
          http://dozer.sourceforge.net/schema/beanmapping.xsd">
  <configuration>
    <custom-converters>
        <converter type="somepackage.MyConverter" >
            <class-a>somepackage.A</class-a>
            <class-b>somepackage.B</class-b>
        </converter>
    </custom-converters>     
  </configuration>
</mappings>

这是CustomConverter：

public class MyConverter implements CustomConverter {
    public Object convert(Object destination, Object source, Class destClass, Class sourceClass){
         if (source == null) {
              return null;
            }
            B dest = null;
            if (source instanceof A) {
                // check to see if the object already exists
                if (destination == null) {
                  dest = new B();
                } else {
                  dest = (B) destination;
                }

              //dest is your parentB instance

              //setting indicatorB value in parentB
                dest.setIndicatorB(((A) source).getIndicatorA()); 

              //creating child instances of B
                B child1B = new B();
                B child2B = new B();  

              //setting indicatorB values to the child instances as well
                child1B.setIndicatorB(((A) source).getIndicatorA());                
                child2B.setIndicatorB(((A) source).getIndicatorA()); 

              //adding child Bs to parentB list
                List<B> listOfBs = new ArrayList<B>(); 
                listOfBs.add(child1B);
                listOfBs.add(child2B);
                dest.setListB(listOfBs);
                return dest;
            }
            return null;        
    }
}

如果只有在运行时才知道childa的数量，则可以使用CustomConverter中的循环来创建相应数量的childb