Front-end AJAX requests a background cross-domain problem (resolution) of another host on the LAN

1. This method is not very appropriate, not safe enough, you need to write an interceptor

Web. XML configuration pointing to interceptors

<filter>        <filter-name>JsonFormat</filter-name>        <filter-class> com.qianmo.qmyj.common.jsonfilter</filter-class>    </filter>    <filter-mapping>        <filter-name>JsonFormat</filter-name>        <url-pattern>*.  do </url-pattern>    </filter-mapping>

 PackageCom.qianmo.qmyj.common;ImportOrg.slf4j.Logger;Importorg.slf4j.LoggerFactory;Importorg.springframework.stereotype.Component;Importjavax.servlet.*;Importjavax.servlet.http.HttpServletRequest;ImportJavax.servlet.http.HttpServletResponse;Importjava.io.IOException;/*** FileName: ${name} * Author:anpei * DATE:2017/5/16 * Description: * History:*/@Component Public classJsonfilterImplementsFilter {PrivateLogger Logger =Loggerfactory.getlogger (GetClass ());  Public voiddestroy () {} Public voidDoFilter (ServletRequest req, Servletresponse resp, filterchain chain)throwsservletexception, IOException {httpservletrequest request=(httpservletrequest) req; HttpServletResponse Response=(HttpServletResponse) resp; Logger.debug ("-------> Accept HTTP requests in the way:" + ((httpservletrequest) req). GetMethod () + "<------"); Request.setcharacterencoding ("UTF-8"); Response.setcharacterencoding ("UTF-8"); Response.setcontenttype ("Text/json"); Response.setheader ("Access-control-allow-origin", "*"); Response.setheader ("Access-control-allow-methods", "POST, GET, OPTIONS, DELETE, Put,head"); Response.setheader ("Access-control-max-age", "3600"); Response.setheader ("Access-control-allow-headers", "X-requested-with,content-type"); Response.setheader ("Access-control-allow-credentials", "true");//Response.AddHeader ("Access-control-allow-headers", "Origin, X-requested-with, Content-type, Accept");//String curorigin = Request.getheader ("Origin");//if (curorigin! = null) {//for (int i = 0; i < originproperties.length; i++) {//logger.debug ("--------> Allow cross-domain access from:" + originproperties[i] + "<---------");//if (Curorigin.equals (Originproperties[i])) {//Response.setheader ("Access-control-allow-origin", curorigin);//                }//            }//} else {//for unsolicited requests (such as entering requests directly in the browser's address bar), only allow our own machines to//Response.setheader ("Access-control-allow-origin", "http://127.0.0.1");//        }//Response.setheader ("Access-control-allow-methods", "POST, GET, OPTIONS, DELETE, Put,head");//request.setcharacterencoding ("UTF-8");//response.setcharacterencoding ("UTF-8");//Response.setcontenttype ("Text/json");Chain.dofilter (req, resp); }     Public voidInit (filterconfig config)throwsservletexception {}}

2. There is another way, I use in eclipse, there is no problem, but do not know why in idea always error, because of time, I did not delve into, chose the above solution, also posted below it.

----------------------Web. xml-------------------------------------------------<filter>        < Filter-name>cors</filter-name>        <filter-class> com.thetransactioncompany.cors.corsfilter</filter-class>    </filter>    < filter-mapping>        <filter-name>CORS</filter-name>        <url-pattern>*< /url-pattern>    </filter-mapping>

------------------------Util Tool Class (Corsconfig)---------------------------------------- Packagecom.commerce.utils;//allow Ajax cross-domain requestsImportOrg.springframework.context.annotation.Bean;Importorg.springframework.context.annotation.Configuration;Importorg.springframework.web.cors.CorsConfiguration;ImportOrg.springframework.web.cors.UrlBasedCorsConfigurationSource;ImportOrg.springframework.web.filter.CorsFilter; @Configuration Public classCorsconfig {Privatecorsconfiguration Buildconfig () {corsconfiguration corsconfiguration=Newcorsconfiguration (); Corsconfiguration.addallowedorigin ("*");//1Corsconfiguration.addallowedheader ("*");//2Corsconfiguration.addallowedmethod ("*");//3        returncorsconfiguration; } @Bean PublicCorsfilter Corsfilter () {Urlbasedcorsconfigurationsource source=NewUrlbasedcorsconfigurationsource (); Source.registercorsconfiguration ("/**", Buildconfig ());//4        return Newcorsfilter (source); }}

Introduction of two Jars

-------------------------pom.xml-------------------------------<dependency>        <groupId> com.github.pagehelper</groupid>        <artifactId>pagehelper</artifactId>        <version> 5.0.0</version>    </dependency>        <dependency>        <groupId> com.thetransactioncompany</groupid>        <artifactId>cors-filter</artifactId>        <version >2.5</version>    </dependency>

 Packagecom.commerce.utils;//allow Ajax cross-domain requestsImportOrg.springframework.context.annotation.Bean;Importorg.springframework.context.annotation.Configuration;Importorg.springframework.web.cors.CorsConfiguration;ImportOrg.springframework.web.cors.UrlBasedCorsConfigurationSource;ImportOrg.springframework.web.filter.CorsFilter; @Configuration Public classCorsconfig {Privatecorsconfiguration Buildconfig () {corsconfiguration corsconfiguration=Newcorsconfiguration (); Corsconfiguration.addallowedorigin ("*");//1Corsconfiguration.addallowedheader ("*");//2Corsconfiguration.addallowedmethod ("*");//3        returncorsconfiguration; } @Bean PublicCorsfilter Corsfilter () {Urlbasedcorsconfigurationsource source=NewUrlbasedcorsconfigurationsource (); Source.registercorsconfiguration ("/**", Buildconfig ());//4        return Newcorsfilter (source); }}

Front-end AJAX requests a background cross-domain problem (resolution) of another host on the LAN