前端调后端跨域问题

1：使用Filter

      

package xxx;

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.HttpServletResponse;

public class CORSFilter implements Filter {

	public void destroy() {
	}

	public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain)
			throws IOException, ServletException {
		HttpServletResponse response = (HttpServletResponse) servletResponse;
		response.setHeader("Access-Control-Allow-Origin", "*");
		response.setHeader("Access-Control-Allow-Methods", "POST, GET, PUT, OPTIONS, DELETE");
		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");
		filterChain.doFilter(servletRequest, servletResponse);
	}

	public void init(FilterConfig filterConfig) throws ServletException {

	}
}

 

web.xml 加上配置 ：

<filter>

    <filter-name>cors</filter-name>

    <filter-class>com.bztech.core.common.CORSFilter</filter-class>

</filter>

<filter-mapping>

    <filter-name>cors</filter-name>

    <url-pattern>/*</url-pattern>

</filter-mapping>

 

 

如果是用的spring4.2以上，(不清楚是不是必须用spring boot)

 

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter;

@Configuration
public class CORSConfiguration {
	@Bean
	public WebMvcConfigurer corsConfigurer() {
		return new WebMvcConfigurerAdapter() {
			@Override
			public void addCorsMappings(CorsRegistry registry) {
				registry.addMapping("/**").allowedHeaders("*").allowedMethods("*").allowedOrigins("*");
			}
		};
	}
}