juneau-rest/juneau-rest-server/src/main/java/org/apache/juneau/rest/util/CachingHttpServletRequest.java

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// * to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance            *
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// *  http://www.apache.org/licenses/LICENSE-2.0                                                                             *
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package org.apache.juneau.rest.util;

import java.io.IOException;

import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;

import org.apache.juneau.internal.IOUtils;

/**
 * Wraps an {@link HttpServletRequest} and preloads the body into memory for debugging purposes.
 */
public class CachingHttpServletRequest extends HttpServletRequestWrapper {

	private final byte[] body;

	/**
	 * Wraps the specified request inside a {@link CachingHttpServletRequest} if it isn't already.
	 *
	 * @param req The request to wrap.
	 * @return The wrapped request.
	 * @throws IOException Thrown by underlying body stream.
	 */
	public static CachingHttpServletRequest wrap(HttpServletRequest req) throws IOException {
		if (req instanceof CachingHttpServletRequest)
			return (CachingHttpServletRequest)req;
		return new CachingHttpServletRequest(req);
	}

	/**
	 * Constructor.
	 *
	 * @param req The request being wrapped.
	 * @throws IOException If body could not be loaded into memory.
	 */
	protected CachingHttpServletRequest(HttpServletRequest req) throws IOException {
		super(req);
		this.body = IOUtils.readBytes(req.getInputStream());
	}

	@Override
	public ServletInputStream getInputStream() {
		return new BoundedServletInputStream(body);
	}

	/**
	 * Returns the body of the servlet request without consuming the stream.
	 *
	 * @return The body of the request.
	 */
	public byte[] getBody() {
		return body;
	}
}