java - Tomcat 严重 : Exception starting filter CorsFilter, ClassNotFoundException

Question

我正在尝试使用以下类为我的 java servlet 启用 CORS:

package com.prosperity.mobile.core;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class CORSFilter implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
    }

    public void doFilter(ServletRequest servletRequest,
            ServletResponse servletResponse, FilterChain chain)
            throws IOException, ServletException {
        HttpServletRequest request = (HttpServletRequest) servletRequest;
        // System.out.println("Request: " + request.getMethod());

        HttpServletResponse resp = (HttpServletResponse) servletResponse;
        resp.addHeader("Access-Control-Allow-Origin", "*");
        resp.addHeader("Access-Control-Allow-Methods", "GET,POST");
        resp.addHeader("Access-Control-Allow-Headers",
                "Origin, X-Requested-With, Content-Type, Accept");

        // Just ACCEPT and REPLY OK if OPTIONS
        if (request.getMethod().equals("OPTIONS")) {
            resp.setStatus(HttpServletResponse.SC_OK);
            return;
        }
        chain.doFilter(request, servletResponse);
    }

    @Override
    public void destroy() {
    }
}

我的 XML:

<filter>    
    <filter-name>CorsFilter</filter-name>
    <filter-class>com.prosperity.mobile.core.CORSFilter</filter-class>
</filter>

<filter-mapping>
    <filter-name>CorsFilter</filter-name>
    <url-pattern>*</url-pattern>
</filter-mapping>

当我尝试将 war 部署到 tomcat 实例时:

SEVERE: Exception starting filter CorsFilter
java.lang.ClassNotFoundException: com.prosperity.mobile.core.CORSFilter
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1718)
    at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1569)
    at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:529)
    at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:511)
    at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:139)
    at org.apache.catalina.core.ApplicationFilterConfig.getFilter(ApplicationFilterConfig.java:258)
    at org.apache.catalina.core.ApplicationFilterConfig.<init>(ApplicationFilterConfig.java:105)
    at org.apache.catalina.core.StandardContext.filterStart(StandardContext.java:4809)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5485)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:632)
    at org.apache.catalina.startup.HostConfig.deployWAR(HostConfig.java:1073)
    at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1857)
    at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source)
    at java.util.concurrent.FutureTask.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

Sep 21, 2015 11:49:35 AM org.apache.catalina.core.StandardContext startInternal
SEVERE: Error filterStart
Sep 21, 2015 11:49:35 AM org.apache.catalina.core.StandardContext startInternal
SEVERE: Context [/ProsperityMobile] startup failed due to previous errors

这似乎是一个非常明显的错误，它提示说它没有找到 CORSFilter 类..但它就在那里，在正确的包和所有东西中？!

注意:我的 tomcat 实例位于:C:\apache-tomcat-7.0.52

Answer 1

解压缩 war 文件并三次检查类文件是否存在。