JS跨域请求外部服务器的资源

tomcat服务器提供的接口，不能在其他域中访问的时候，需要增 access-control-allow-origin:*

以下操作均在需要被访问的项目中设置

1、编写拦截器代码

 package com.soft.filter;
/**
 * created by administrator on 2017/2/6.
 */
import javax.servlet.*;
import javax.servlet.http.httpservletresponse;
import java.io.ioexception;
public class corsfilter implements filter {
  @override
  public void init(filterconfig filterconfig) throws servletexception {
  }
  @override
  public void dofilter(servletrequest servletrequest, servletresponse servletresponse, filterchain filterchain) throws ioexception, servletexception {
    httpservletresponse httpresponse = (httpservletresponse) servletresponse;
    httpresponse.addheader("access-control-allow-origin", "*");
    filterchain.dofilter(servletrequest, servletresponse);
  }
  @override
  public void destroy() {
  }
}

2、配置web.xml

<filter>
  <filter-name>corsfilter</filter-name>
  <filter-class>com.omiaozu.manager.filter.corsfilter</filter-class>
</filter>
<filter-mapping>
  <filter-name>corsfilter</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>