getCanonicalName和getSimpleName getName的区别与应用

接口:

1. package com.test;
2. public interface Fruit {
3. }

一个实现类:

1. package com.test;
2. public class Apple implements Fruit {
3. }

基本测试类:

    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

1. public <T> List<T> getRecords(Class<T> c,Date startDate,Date endDate){
2. StringBuilder hql = new StringBuilder("select t from ");
3. hql.append(c.getCanonicalName());
4. hql.append(" t where t.statTime>=:startTime and t.statTime<:endTime ");
5. Query query = sessionFactory.getCurrentSession().createQuery(hql.toString());
6. query.setParameter("startTime", startDate);
7. query.setParameter("endTime", endDate);
8. return query.list();
9. }
10. }

 

http://blog.csdn.net/wirelessqa/article/details/8151889