ssm整合篇-配置跨域访问-前后端分离配置跨域

域名：域名不同也就意味着ip地址不同。

端口号：port，即使是同一台电脑，每个应用程序都占用不同的端口号。

非同源限制

无法读取非同源网页的 、 和

无法接触非同源网页的 DOM

无法向非同源地址发送 AJAX 请求

跨域解决方案 1. 使用注解@ 直接在类或方法前加上@注解即可允许所有ip跨域访问加在类上表示该的所有方法都支持跨域加在中的方法上表示仅该方法支持跨域

@CrossOrigin // 允许所有ip跨域
@CrossOrigin(origins = "192.168.0.0") // 允许指定ip跨域

2. 在配置文件中配置跨域请求

<mvc:cors><mvc:mapping path="/**" allowed-origins="*"allowed-methods="POST,GET,DELETE,PUT"allowed-headers="Content-Type, Access-Control-Allow-Headers,Authorization,X-Requested-with"allow-credentials="true"/>mvc:cors>

3. 使用cors-包配置跨域

<dependency><groupId>com.thetransactioncompanygroupId><artifactId>cors-filterartifactId><version>2.10version>dependency>

在web.xml注册跨域过滤器

    <filter><filter-name>corsfilter-name><filter-class>com.thetransactioncompany.cors.CORSFilterfilter-class><init-param><param-name>cors.allowOriginparam-name><param-value>*param-value>init-param><init-param><param-name>cors.supportedMethodsparam-name><param-value>GET,POST,PUT,DELETEparam-value>init-param><init-param><param-name>cors.supportedHeadersparam-name><param-value>Content-Type, Access-Control-Allow-Headers,Authorization,X-Requested-withparam-value>init-param><init-param><param-name>cors.exposedHeadersparam-name><param-value>Set-cookieparam-value>init-param><init-param><param-name>cors.supportsCredentialsparam-name><param-value>trueparam-value>init-param>filter><filter-mapping><filter-name>corsfilter-name>
<url-pattern>/*url-pattern>filter-mapping>

4. 当然，也可以手写跨域请求过滤器

@Filter("/*")
public class CrossingFilter implements Filter {private boolean isCross = false;@Overridepublic void destroy() {isCross = false;}@Overridepublic void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)throws IOException, ServletException {if (isCross) {HttpServletRequest httpServletRequest = (HttpServletRequest) request;HttpServletResponse httpServletResponse = (HttpServletResponse) response;System.out.println("拦截请求: " + httpServletRequest.getServletPath());httpServletResponse.setHeader("Access-Control-Allow-Origin", "*");// httpServletResponse.setHeader("Access-Control-Allow-Methods", "*"); // 表示所有请求都有效httpServletResponse.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");httpServletResponse.setHeader("Access-Control-Max-Age", "0");httpServletResponse.setHeader("Access-Control-Allow-Headers","Origin, No-Cache, X-Requested-With, If-Modified-Since, Pragma, Last-Modified, Cache-Control, Expires, Content-Type, X-E4M-With,userId,token");httpServletResponse.setHeader("Access-Control-Allow-Credentials", "true");httpServletResponse.setHeader("XDomainRequestAllowed", "1");}chain.doFilter(request, response);}@Overridepublic void init(FilterConfig filterConfig) throws ServletException {String isCrossStr = filterConfig.getInitParameter("IsCross");isCross = isCrossStr.equals("true") ? true : false;System.out.println("跨域开启状态：" + isCrossStr);}
}

跨域请求对基础方案就是这几种。也还有更好的解决方案，但暂时还不了解。