java中判断一个对象是否实现了某个接口

1. /***************************************************************************
2.          * 判断对象o实现的所有接口中是否有szInterface 
3.          * 2008-08-07 修正多继承中判断接口的功能，
4.          * 以及修正接口继承后的判断功能
5.          * package test;
6.          * 
7.          * public interface ITest extends Serializable
8.          * public class Test1 implements ITest
9.          * public class Test2 extends Test1
10.          * public class Test3 extends Test2 
11.          * 
12.          * isInterface(Test3.class, "java.io.Serializable") = true
13.          * isInterface(Test3.class, "test.ITest") = true
14.          * @param c
15.          * @param szInterface
16.          * @return
17.          */
18.         public boolean isInterface(Class c, String szInterface)
19.         {
20.                 Class[] face = c.getInterfaces();
21.                 for (int i = 0, j = face.length; i < j; i++) 
22.                 {
23.                         if(face[i].getName().equals(szInterface))
24.                         {
25.                                 return true;
26.                         }
27.                         else
28.                         { 
29.                                 Class[] face1 = face[i].getInterfaces();
30.                                 for(int x = 0; x < face1.length; x++)
31.                                 {
32.                                         if(face1[x].getName().equals(szInterface))
33.                                         {
34.                                                 return true;
35.                                         }
36.                                         else if(isInterface(face1[x], szInterface))
37.                                         {
38.                                                 return true;
39.                                         }
40.                                 }
41.                         }
42.                 }
43.                 if (null != c.getSuperclass())
44.                 {
45.                         return isInterface(c.getSuperclass(), szInterface);
46.                 }
47.                 return false;
48.         }