java 允许跨域

就在刚刚，朋友问我跨域怎么解决,正好前段时间刚做过,那我就来分享一下吧。

首先创建Httpfilter类，在 Controller 同级下创建 1.png
Httpfilter类代码：

    package com.Verification.filter;

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;

import org.apache.http.HttpStatus;

public class Httpfilter implements Filter {

@Override
public void destroy() {
    // TODO 自动生成的方法存根
    
}

@Override
public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
    HttpServletResponse response = (HttpServletResponse) servletResponse;
    HttpServletRequest request = (HttpServletRequest) servletRequest;
    // 指定允许其他域名访问
    response.setHeader("Access-Control-Allow-Origin", "*");
    // 响应类型
    response.setHeader("Access-Control-Allow-Methods", "POST, GET, DELETE, OPTIONS, DELETE");
    // 响应头设置
    response.setHeader("Access-Control-Allow-Headers", "Content-Type, x-requested-with, X-Custom-Header, HaiYi-Access-Token");
    if ("OPTIONS".equals(request.getMethod())){
    response.setStatus(HttpStatus.SC_NO_CONTENT);
    }
    filterChain.doFilter(servletRequest, servletResponse);
}

@Override
public void init(FilterConfig arg0) throws ServletException {
    // TODO 自动生成的方法存根
    
}

}

然后：

2.png

xml添加：

<filter>
<filter-name>httpfilter</filter-name>
<filter-class>com.Verification.filter.Httpfilter</filter-class>
</filter>
<filter-mapping>
<filter-name>httpfilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>

最后按ctrl然后鼠标点击xml里的com.Verification.filter.Httpfilter能进入这个页面就算成功。
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