解决ajax跨域

1、添加jar包：
    cors-filter-1.7.jar
    java-property-utils-1.9.jar

2、web.xml中添加filter

   <filter>
    <filter-name>CORS</filter-name>
    <filter-class>com.thetransactioncompany.cors.CORSFilter</filter-class>
    <init-param>
      <param-name>cors.allowOrigin</param-name>
      <param-value>*</param-value>
    </init-param>
    <init-param>
      <param-name>cors.supportedMethods</param-name>
      <param-value>GET, POST, HEAD, PUT, DELETE</param-value>
    </init-param>
    <init-param>
      <param-name>cors.supportedHeaders</param-name>
      <param-value>Accept, Origin, X-Requested-With, Content-Type, Last-Modified, Authorization</param-value>//request的header中可以包含的内容，可以手动添加
    </init-param>
    <init-param>
      <param-name>cors.exposedHeaders</param-name>
      <param-value>Set-Cookie</param-value>
    </init-param>
    <init-param>
      <param-name>cors.supportsCredentials</param-name>
      <param-value>true</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>CORS</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>