palfish 2017-06-09 05:46 采纳率: 100%
浏览 3235
已采纳

URLClassLoader加载本地类文件为什么总是报ClassNotFound?求大神解惑

public class ServletProcessor1 {

public void process(Request request, Response response) {
        String uri            = request.getUri();
        String servletName    = uri.substring(uri.lastIndexOf("/") + 1);
        URLClassLoader loader = null;

        try {
            // create a URLClassLoader
            URLStreamHandler streamHandler = null;

            URL[] urls        = new URL[1];
            File classPath    = new File(HttpServer1.WEB_ROOT);
            String repository = (new URL("file", null, 
                classPath.getCanonicalPath() + File.separator)).toString() ;
            urls[0]           = new URL(null, repository, streamHandler);
            loader            = new URLClassLoader(urls);
            System.out.println(loader.findResource(servletName));
        }
        catch (IOException e) {
            System.out.println(e.toString() );
        }

        Class<?> myClass = null;

        try {
            myClass = loader.loadClass(servletName);
        }
        catch (ClassNotFoundException e) {
            System.out.println(e.toString());
        }
        Servlet servlet = null;
        try {
            servlet = (Servlet) myClass.newInstance();
            servlet.service((ServletRequest) request, (ServletResponse) response);
        }
        catch (Exception e) {
            System.out.println(e.toString());
        }
        catch (Throwable e) {
            System.out.println(e.toString());
        }
}

}

java.lang.ClassNotFoundException: PrimitiveServlet
java.lang.NullPointerException

Exception in thread "main" java.lang.NullPointerException
at ex02.pyrmont.HttpServer1.await(HttpServer1.java:50)
at ex02.pyrmont.HttpServer1.main(HttpServer1.java:22)

  • 写回答

3条回答 默认 最新

  • lihongbiao0610 2017-06-09 06:02
    关注

    servletName应该是包名+类名。如com.test.PrimitiveServlet

    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论
查看更多回答(2条)

报告相同问题?

悬赏问题

  • ¥15 outlook无法配置成功
  • ¥15 Pwm双极模式H桥驱动控制电机
  • ¥30 这是哪个作者做的宝宝起名网站
  • ¥60 版本过低apk如何修改可以兼容新的安卓系统
  • ¥25 由IPR导致的DRIVER_POWER_STATE_FAILURE蓝屏
  • ¥50 有数据,怎么建立模型求影响全要素生产率的因素
  • ¥50 有数据,怎么用matlab求全要素生产率
  • ¥15 TI的insta-spin例程
  • ¥15 完成下列问题完成下列问题
  • ¥15 C#算法问题, 不知道怎么处理这个数据的转换