泛型积累

获取到子类设置的泛型class

public abstract class PaginationDataModel<T extends IEntity>

 

class AgentDataModel extends PaginationDataModel<AgentSmp>

 

在PaginationDataModel类中可以取到具体子类中设置的class，能获取到AgentSmp class

 

 Class itemClass;

public PaginationDataModel (){

   Class clazz = getClass();
   while (!(clazz.getGenericSuperclass() instanceof ParameterizedType)) {
    clazz = clazz.getSuperclass();
   }
   Object o = ((ParameterizedType) clazz.getGenericSuperclass()).getActualTypeArguments()[0];

   Class itemClass;
   if (o instanceof TypeVariable) {
    itemClass = (Class<T>) ((TypeVariable) o).getBounds()[0];
   } else {
    itemClass = (Class<T>) o;
   }

1】类型上定义泛型

public interface TreeNode<T>{

2】方法上定义泛型

泛型方法必须有返回值,没有返回值的方法不能使用泛型

public <E extends BaseEntity> void dataTransferToPoList(List<E> vos,List<E> pos){

       for(E vo:vos){//source

           boolean add=true;

           for(E po:pos){//target

              if(vo.equals(po)){//update

                  vo.dataTransferToPo(po);

                  add=false;

                  break;

              }

           }

           if(add){

              pos.add(vo);

           }

       }

    }

泛型方法中不能直接对泛型进行new操作

public <T extends Record> T getRecord(T t){

       //

       return t;

    }