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copied!<p>As an aside, an alternative way to solve this problem is to not use the filter chain and instead build your own interceptor component, perhaps using aspects, which can operate on the parsed request body. It will also likely be more efficient as you are only converting the request <code>InputStream</code> into your own model object once.</p> <p>However, I still think it's reasonable to want to read the request body more than once particularly as the request moves through the filter chain. I would typically use filter chains for certain operations that I want to keep at the HTTP layer, decoupled from the service components.</p> <p>As suggested by <a href="https://stackoverflow.com/a/10211289/551467">Will Hartung</a> I achieved this by extending <code>HttpServletRequestWrapper</code>, consuming the request <code>InputStream</code> and essentially caching the bytes.</p> <pre><code>public class MultiReadHttpServletRequest extends HttpServletRequestWrapper { private ByteArrayOutputStream cachedBytes; public MultiReadHttpServletRequest(HttpServletRequest request) { super(request); } @Override public ServletInputStream getInputStream() throws IOException { if (cachedBytes == null) cacheInputStream(); return new CachedServletInputStream(); } @Override public BufferedReader getReader() throws IOException{ return new BufferedReader(new InputStreamReader(getInputStream())); } private void cacheInputStream() throws IOException { /* Cache the inputstream in order to read it multiple times. For * convenience, I use apache.commons IOUtils */ cachedBytes = new ByteArrayOutputStream(); IOUtils.copy(super.getInputStream(), cachedBytes); } /* An inputstream which reads the cached request body */ public class CachedServletInputStream extends ServletInputStream { private ByteArrayInputStream input; public CachedServletInputStream() { /* create a new input stream from the cached request body */ input = new ByteArrayInputStream(cachedBytes.toByteArray()); } @Override public int read() throws IOException { return input.read(); } } } </code></pre> <p>Now the request body can be read more than once by wrapping the original request before passing it through the filter chain:</p> <pre><code>public class MyFilter implements Filter { @Override public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException { /* wrap the request in order to read the inputstream multiple times */ MultiReadHttpServletRequest multiReadRequest = new MultiReadHttpServletRequest((HttpServletRequest) request); /* here I read the inputstream and do my thing with it; when I pass the * wrapped request through the filter chain, the rest of the filters, and * request handlers may read the cached inputstream */ doMyThing(multiReadRequest.getInputStream()); //OR anotherUsage(multiReadRequest.getReader()); chain.doFilter(multiReadRequest, response); } } </code></pre> <p>This solution will also allow you to read the request body multiple times via the <code>getParameterXXX</code> methods because the underlying call is <code>getInputStream()</code>, which will of course read the cached request <code>InputStream</code>.</p>

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