Java的泛型反射

If the superclass is a parameterized type, the {@code Type}
     * object returned must accurately reflect the actual type
     * parameters used in the source code. T

package entity;


import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;

/**
 * Created by Administrator on 2016/11/27 0027.
 */
public class BaseDaoImpl<T> implements BaseDao<T> {

    public BaseDaoImpl(){
        Type type = getClass().getGenericSuperclass();
        Type[] params = ((ParameterizedType)type).getActualTypeArguments();
        System.out.println((Class<T>)params[0]);
    }

    public T findByid(int id) {
        return null;
    }
}

package entity;

/**
 * Created by Administrator on 2016/11/27 0027.
 */
public class UserDaoImpl extends BaseDaoImpl<User> {
}

package entity;

/**
 * Created by Administrator on 2016/11/27 0027.
 */
public interface BaseDao<T> {
   public T findByid(int id);
}

package entity;

import org.junit.Test;

/**
 * Created by Administrator on 2016/11/27 0027.
 */
public class GenericTest {
    @Test
    public void testGeneric(){
        UserDaoImpl baseDao = new UserDaoImpl();
        //BaseDaoImpl<User> baseDao1 = new BaseDaoImpl<User>();
    }
}