Subversion Repositories SmartDukaan

package com.spice.profitmandi.web.filter;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;

public class RequestCachingFilter implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {}

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        HttpServletRequest httpRequest = (HttpServletRequest) request;
        if ("POST".equalsIgnoreCase(httpRequest.getMethod())
                && !isMultipart(httpRequest)
                && !isFormEncoded(httpRequest)) {
            chain.doFilter(new CachedBodyRequest(httpRequest), response);
        } else {
            chain.doFilter(request, response);
        }
    }

    @Override
    public void destroy() {}

    private boolean isMultipart(HttpServletRequest request) {
        String contentType = request.getContentType();
        return contentType != null && contentType.toLowerCase().startsWith("multipart/");
    }

    private boolean isFormEncoded(HttpServletRequest request) {
        String contentType = request.getContentType();
        return contentType != null && contentType.toLowerCase().startsWith("application/x-www-form-urlencoded");
    }

    public static class CachedBodyRequest extends HttpServletRequestWrapper {
        private final byte[] body;

        public CachedBodyRequest(HttpServletRequest request) throws IOException {
            super(request);
            InputStream is = request.getInputStream();
            ByteArrayOutputStream baos = new ByteArrayOutputStream(1024);
            byte[] buf = new byte[1024];
            int len;
            while ((len = is.read(buf)) != -1) {
                baos.write(buf, 0, len);
            }
            this.body = baos.toByteArray();
        }

        @Override
        public ServletInputStream getInputStream() {
            ByteArrayInputStream bais = new ByteArrayInputStream(body);
            return new ServletInputStream() {
                @Override public int read() { return bais.read(); }
                @Override public boolean isFinished() { return bais.available() == 0; }
                @Override public boolean isReady() { return true; }
                @Override public void setReadListener(ReadListener listener) {}
            };
        }

        @Override
        public BufferedReader getReader() {
            return new BufferedReader(new InputStreamReader(getInputStream()));
        }

        public byte[] getCachedBody() {
            return body;
        }
    }
}