gt: 			if (!paramMap.containsKey(paramName)) {
context: /*
   * Copyright 2002-2017 the original author or authors.
   *
   * Licensed under the Apache License, Version 2.0 (the "License");
   * you may not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   *      http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  package org.springframework.web.multipart.support;
  
  import java.io.File;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.Serializable;
  import java.nio.charset.Charset;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.Enumeration;
  import java.util.LinkedHashMap;
  import java.util.LinkedHashSet;
  import java.util.Map;
  import java.util.Set;
  import javax.servlet.http.HttpServletRequest;
  import javax.servlet.http.Part;
  
  import org.springframework.http.HttpHeaders;
  import org.springframework.util.FileCopyUtils;
  import org.springframework.util.LinkedMultiValueMap;
  import org.springframework.util.MultiValueMap;
  import org.springframework.web.multipart.MultipartException;
  import org.springframework.web.multipart.MultipartFile;
  
  /**
   * Spring MultipartHttpServletRequest adapter, wrapping a Servlet 3.0 HttpServletRequest
   * and its Part objects. Parameters get exposed through the native request's getParameter
   * methods - without any custom processing on our side.
   *
   * @author Juergen Hoeller
   * @author Rossen Stoyanchev
   * @since 3.1
   */
  public class StandardMultipartHttpServletRequest extends AbstractMultipartHttpServletRequest {
  
  	private static final String CONTENT_DISPOSITION = "content-disposition";
  
  	private static final String FILENAME_KEY = "filename=";
  
  	private static final String FILENAME_WITH_CHARSET_KEY = "filename*=";
  
  	private static final Charset US_ASCII = Charset.forName("us-ascii");
  
  
  	private Set<String> multipartParameterNames;
  
  
  	/**
  	 * Create a new StandardMultipartHttpServletRequest wrapper for the given request,
  	 * immediately parsing the multipart content.
  	 * @param request the servlet request to wrap
  	 * @throws MultipartException if parsing failed
  	 */
  	public StandardMultipartHttpServletRequest(HttpServletRequest request) throws MultipartException {
  		this(request, false);
  	}
  
  	/**
  	 * Create a new StandardMultipartHttpServletRequest wrapper for the given request.
  	 * @param request the servlet request to wrap
  	 * @param lazyParsing whether multipart parsing should be triggered lazily on
  	 * first access of multipart files or parameters
  	 * @throws MultipartException if an immediate parsing attempt failed
  	 */
  	public StandardMultipartHttpServletRequest(HttpServletRequest request, boolean lazyParsing) throws MultipartException {
  		super(request);
  		if (!lazyParsing) {
  			parseRequest(request);
  		}
  	}
  
  
  	private void parseRequest(HttpServletRequest request) {
  		try {
  			Collection<Part> parts = request.getParts();
  			this.multipartParameterNames = new LinkedHashSet<String>(parts.size());
  			MultiValueMap<String, MultipartFile> files = new LinkedMultiValueMap<String, MultipartFile>(parts.size());
  			for (Part part : parts) {
  				String disposition = part.getHeader(CONTENT_DISPOSITION);
  				String filename = extractFilename(disposition);
  				if (filename == null) {
  					filename = extractFilenameWithCharset(disposition);
  				}
  				if (filename != null) {
  					files.add(part.getName(), new StandardMultipartFile(part, filename));
  				}
  				else {
  					this.multipartParameterNames.add(part.getName());
  				}
  			}
  			setMultipartFiles(files);
  		}
  		catch (Throwable ex) {
  			throw new MultipartException("Could not parse multipart servlet request", ex);
  		}
  	}
  
  	private String extractFilename(String contentDisposition, String key) {
  		if (contentDisposition == null) {
  			return null;
  		}
  		int startIndex = contentDisposition.indexOf(key);
  		if (startIndex == -1) {
  			return null;
  		}
  		String filename = contentDisposition.substring(startIndex + key.length());
  		if (filename.startsWith("\"")) {
  			int endIndex = filename.indexOf("\"", 1);
  			if (endIndex != -1) {
  				return filename.substring(1, endIndex);
  			}
  		}
  		else {
  			int endIndex = filename.indexOf(";");
  			if (endIndex != -1) {
  				return filename.substring(0, endIndex);
  			}
  		}
  		return filename;
  	}
  
  	private String extractFilename(String contentDisposition) {
  		return extractFilename(contentDisposition, FILENAME_KEY);
  	}
  
  	private String extractFilenameWithCharset(String contentDisposition) {
  		String filename = extractFilename(contentDisposition, FILENAME_WITH_CHARSET_KEY);
  		if (filename == null) {
  			return null;
  		}
  		int index = filename.indexOf("'");
  		if (index != -1) {
  			Charset charset = null;
  			try {
  				charset = Charset.forName(filename.substring(0, index));
  			}
  			catch (IllegalArgumentException ex) {
  				// ignore
  			}
  			filename = filename.substring(index + 1);
  			// Skip language information..
  			index = filename.indexOf("'");
  			if (index != -1) {
  				filename = filename.substring(index + 1);
  			}
  			if (charset != null) {
  				filename = new String(filename.getBytes(US_ASCII), charset);
  			}
  		}
  		return filename;
  	}
  
  
  	@Override
  	protected void initializeMultipart() {
  		parseRequest(getRequest());
  	}
  
  	@Override
  	public Enumeration<String> getParameterNames() {
  		if (this.multipartParameterNames == null) {
  			initializeMultipart();
  		}
  		if (this.multipartParameterNames.isEmpty()) {
  			return super.getParameterNames();
  		}
  
  		// Servlet 3.0 getParameterNames() not guaranteed to include multipart form items
  		// (e.g. on WebLogic 12) -> need to merge them here to be on the safe side
  		Set<String> paramNames = new LinkedHashSet<String>();
  		Enumeration<String> paramEnum = super.getParameterNames();
  		while (paramEnum.hasMoreElements()) {
  			paramNames.add(paramEnum.nextElement());
  		}
  		paramNames.addAll(this.multipartParameterNames);
  		return Collections.enumeration(paramNames);
  	}
  
  	@Override
  	public Map<String, String[]> getParameterMap() {
  		if (this.multipartParameterNames == null) {
  			initializeMultipart();
  		}
  		if (this.multipartParameterNames.isEmpty()) {
  			return super.getParameterMap();
  		}
  
  		// Servlet 3.0 getParameterMap() not guaranteed to include multipart form items
  		// (e.g. on WebLogic 12) -> need to merge them here to be on the safe side
  		Map<String, String[]> paramMap = new LinkedHashMap<String, String[]>();
  		paramMap.putAll(super.getParameterMap());
  		for (String paramName : this.multipartParameterNames) {
  