CORSFilter.java

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 doFilter(ServletRequest req, ServletResponse res, FilterChain chain) throws IOException, ServletException {  
        HttpServletResponse response = (HttpServletResponse) res;  
        response.setHeader("Access-Control-Allow-Origin", "http://localhost:3000");  
        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");  
        chain.doFilter(req, res);  
    }  
  
    public void init(FilterConfig filterConfig) {}  
  
    public void destroy() {}  
  
}