CORS(跨源资源共享)是一种安全机制,用于在Web应用程序中允许或禁止来自不同源的HTTP请求
创建一个名为CORSFilter.java
的新类,并实现javax.servlet.Filter
接口。在这个类中,你需要实现以下三个方法:init()
, doFilter()
和destroy()
。
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.annotation.WebFilter;
import javax.servlet.http.HttpServletResponse;
@WebFilter(asyncSupported = true, urlPatterns = { "/*" })
public class CORSFilter implements Filter {
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
HttpServletResponse httpResponse = (HttpServletResponse) response;
httpResponse.setHeader("Access-Control-Allow-Origin", "*");
httpResponse.setHeader("Access-Control-Allow-Methods", "POST, GET, PUT, OPTIONS, DELETE");
httpResponse.setHeader("Access-Control-Max-Age", "3600");
httpResponse.setHeader("Access-Control-Allow-Headers", "Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With");
chain.doFilter(request, response);
}
@Override
public void init(FilterConfig filterConfig) throws ServletException {
}
@Override
public void destroy() {
}
}
如果你使用的是Spring Boot,可以通过添加@Bean
到你的主应用程序类中来配置CORS。例如:
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.annotation.Bean;
import org.springframework.web.servlet.config.annotation.CorsRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
@SpringBootApplication
public class Application {
public static void main(String[] args) {
SpringApplication.run(Application.class, args);
}
@Bean
public WebMvcConfigurer corsConfigurer() {
return new WebMvcConfigurer() {
@Override
public void addCorsMappings(CorsRegistry registry) {
registry.addMapping("/**")
.allowedOrigins("*")
.allowedMethods("GET", "POST", "PUT", "DELETE", "OPTIONS")
.allowedHeaders("*")
.maxAge(3600);
}
};
}
}
如果你使用的是JAX-RS(Jersey),可以通过创建一个名为CORSFilter.java
的新类,并实现ContainerResponseFilter
接口来配置CORS。例如:
import javax.ws.rs.container.ContainerRequestContext;
import javax.ws.rs.container.ContainerResponseContext;
import javax.ws.rs.container.ContainerResponseFilter;
import javax.ws.rs.core.MultivaluedMap;
import java.io.IOException;
public class CORSFilter implements ContainerResponseFilter {
@Override
public void filter(ContainerRequestContext requestContext, ContainerResponseContext responseContext)
throws IOException {
MultivaluedMap<String, Object> headers = responseContext.getHeaders();
headers.add("Access-Control-Allow-Origin", "*");
headers.add("Access-Control-Allow-Methods", "GET, POST, DELETE, PUT, OPTIONS");
headers.add("Access-Control-Allow-Headers", "Content-Type, Authorization, X-Requested-With");
}
}
然后,确保在你的应用程序中注册此过滤器。例如,在Application
类中添加以下代码:
import org.glassfish.jersey.server.ResourceConfig;
public class Application extends ResourceConfig {
public Application() {
packages("your.package.name");
register(CORSFilter.class);
}
}
这些方法应该能帮助你解决Java中的CORS预检请求问题。根据你的项目需求和架构选择合适的方法进行配置。