接口:
package com.test;
public interface Fruit {
}
一個實現類:
package com.test;
public class Apple implements Fruit {
}
基本測試類:
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
}
}
實際應用: hql的泛型查詢
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();
}
}