接口:
Java代码
- package com.test;
- public interface Fruit {
- }
一个实现类:
Java代码
- package com.test;
- public class Apple implements Fruit {
- }
基本测试类:
Java代码
- package com.test;
- import java.util.ArrayList;
- import java.util.List;
- public class TestName {
- public static void main(String[] args) {
- Fruit apple=new Apple();
- System.out.println(apple.getClass().getCanonicalName());//返回com.test.Apple
- System.out.println(apple.getClass().getSimpleName());//Apple
- System.out.println(apple.getClass().getName());//返回com.test.Apple
- Apple[] arrApple=new Apple[]{};
- System.out.println(arrApple.getClass().getCanonicalName());//返回com.test.Apple[]
- System.out.println(arrApple.getClass().getSimpleName());//返回Apple[]
- System.out.println(arrApple.getClass().getName());//返回[Lcom.test.Apple;
- System.out.println(String.class.getCanonicalName());//返回java.lang.String
- System.out.println(String.class.getSimpleName());//返回String
- System.out.println(String.class.getName());//返回java.lang.String
- System.out.println(int.class.getCanonicalName());//返回int
- System.out.println(int.class.getSimpleName());//返回int
- System.out.println(int.class.getName());//返回int
- Apple a1=new Apple();
- Apple a2=new Apple();
- List<Apple> appleList=new ArrayList<Apple>();
- appleList.add(a1);
- appleList.add(a2);
- System.out.println(appleList.getClass().getCanonicalName());//返回java.util.ArrayList
- System.out.println(appleList.getClass().getSimpleName());//返回ArrayList
- System.out.println(appleList.getClass().getName());//返回java.util.ArrayList
- }
- }
实际应用: hql的泛型查询
Java代码
- public <T> List<T> getRecords(Class<T> c,Date startDate,Date endDate){
- StringBuilder hql = new StringBuilder("select t from ");
- hql.append(c.getCanonicalName());
- hql.append(" t where t.statTime>=:startTime and t.statTime<:endTime ");
- Query query = sessionFactory.getCurrentSession().createQuery(hql.toString());
- query.setParameter("startTime", startDate);
- query.setParameter("endTime", endDate);
- return query.list();
- }
- }
时间: 2024-10-06 04:07:16