Java Servlet API 4.0.1 Source Code Files are important if you want to compile them with different JDK releases.

You can get Java Servlet API 4.0.1 Source Code Files from Servlet API Maven Website in the "4.0.1/" folder.

You can also browse Java Servlet API 4.0.1 Source Code files below:

⏎ javax/servlet/http/HttpUtils.java

/*
 * Copyright (c) 1997-2018 Oracle and/or its affiliates. All rights reserved.
 * Copyright 2004 The Apache Software Foundation
 *
 * 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 javax.servlet.http;

import javax.servlet.ServletInputStream;
import java.util.Hashtable;
import java.util.ResourceBundle;
import java.util.StringTokenizer;
import java.io.IOException;

/**
 * @deprecated		As of Java(tm) Servlet API 2.3. 
 *			These methods were only useful
 *			with the default encoding and have been moved
 *			to the request interfaces.
 *
 */
@Deprecated
public class HttpUtils {

    private static final String LSTRING_FILE =
	"javax.servlet.http.LocalStrings";
    private static ResourceBundle lStrings =
	ResourceBundle.getBundle(LSTRING_FILE);
        
    
    /**
     * Constructs an empty <code>HttpUtils</code> object.
     */
    public HttpUtils() {}
    

    /**
     * Parses a query string passed from the client to the
     * server and builds a <code>HashTable</code> object
     * with key-value pairs. 
     * The query string should be in the form of a string
     * packaged by the GET or POST method, that is, it
     * should have key-value pairs in the form <i>key=value</i>,
     * with each pair separated from the next by a &amp; character.
     *
     * <p>A key can appear more than once in the query string
     * with different values. However, the key appears only once in 
     * the hashtable, with its value being
     * an array of strings containing the multiple values sent
     * by the query string.
     * 
     * <p>The keys and values in the hashtable are stored in their
     * decoded form, so
     * any + characters are converted to spaces, and characters
     * sent in hexadecimal notation (like <i>%xx</i>) are
     * converted to ASCII characters.
     *
     * @param s		a string containing the query to be parsed
     *
     * @return		a <code>HashTable</code> object built
     * 			from the parsed key-value pairs
     *
     * @exception IllegalArgumentException if the query string is invalid
     */
    public static Hashtable<String, String[]> parseQueryString(String s) {

        String valArray[] = null;
	
        if (s == null) {
            throw new IllegalArgumentException();
        }

        Hashtable<String, String[]> ht = new Hashtable<String, String[]>();
        StringBuilder sb = new StringBuilder();
        StringTokenizer st = new StringTokenizer(s, "&");
        while (st.hasMoreTokens()) {
        String pair = st.nextToken();
        int pos = pair.indexOf('=');
        if (pos == -1) {
            // XXX
            // should give more detail about the illegal argument
            throw new IllegalArgumentException();
        }
        String key = parseName(pair.substring(0, pos), sb);
        String val = parseName(pair.substring(pos+1, pair.length()), sb);
        if (ht.containsKey(key)) {
            String oldVals[] = ht.get(key);
            valArray = new String[oldVals.length + 1];
            for (int i = 0; i < oldVals.length; i++) {
                valArray[i] = oldVals[i];
            }
            valArray[oldVals.length] = val;
        } else {
            valArray = new String[1];
            valArray[0] = val;
        }
        ht.put(key, valArray);
    }

	return ht;
    }


    /**
     *
     * Parses data from an HTML form that the client sends to 
     * the server using the HTTP POST method and the 
     * <i>application/x-www-form-urlencoded</i> MIME type.
     *
     * <p>The data sent by the POST method contains key-value
     * pairs. A key can appear more than once in the POST data
     * with different values. However, the key appears only once in 
     * the hashtable, with its value being
     * an array of strings containing the multiple values sent
     * by the POST method.
     *
     * <p>The keys and values in the hashtable are stored in their
     * decoded form, so
     * any + characters are converted to spaces, and characters
     * sent in hexadecimal notation (like <i>%xx</i>) are
     * converted to ASCII characters.
     *
     * @param len	an integer specifying the length,
     *			in characters, of the 
     *			<code>ServletInputStream</code>
     *			object that is also passed to this
     *			method
     *
     * @param in	the <code>ServletInputStream</code>
     *			object that contains the data sent
     *			from the client
     * 
     * @return		a <code>HashTable</code> object built
     *			from the parsed key-value pairs
     *
     * @exception IllegalArgumentException if the data
     * sent by the POST method is invalid
     */
    public static Hashtable<String, String[]> parsePostData(int len, 
                ServletInputStream in) {
	// XXX
	// should a length of 0 be an IllegalArgumentException
	
	if (len <=0) {
            // cheap hack to return an empty hash
	    return new Hashtable<String, String[]>(); 
        }

	if (in == null) {
	    throw new IllegalArgumentException();
	}
	
	//
	// Make sure we read the entire POSTed body.
	//
        byte[] postedBytes = new byte [len];
        try {
            int offset = 0;
       
	    do {
		int inputLen = in.read (postedBytes, offset, len - offset);
		if (inputLen <= 0) {
		    String msg = lStrings.getString("err.io.short_read");
		    throw new IllegalArgumentException (msg);
		}
		offset += inputLen;
	    } while ((len - offset) > 0);

	} catch (IOException e) {
	    throw new IllegalArgumentException(e.getMessage());
	}

        // XXX we shouldn't assume that the only kind of POST body
        // is FORM data encoded using ASCII or ISO Latin/1 ... or
        // that the body should always be treated as FORM data.
        //

        try {
            String postedBody = new String(postedBytes, 0, len, "8859_1");
            return parseQueryString(postedBody);
        } catch (java.io.UnsupportedEncodingException e) {
            // XXX function should accept an encoding parameter & throw this
            // exception.  Otherwise throw something expected.
            throw new IllegalArgumentException(e.getMessage());
        }
    }


    /*
     * Parse a name in the query string.
     */
    private static String parseName(String s, StringBuilder sb) {
        sb.setLength(0);
        for (int i = 0; i < s.length(); i++) {
            char c = s.charAt(i); 
            switch (c) {
                case '+':
                    sb.append(' ');
                    break;
                case '%':
                    try {
                        sb.append((char) Integer.parseInt(s.substring(i+1, i+3), 
                                16));
                        i += 2;
                    } catch (NumberFormatException e) {
                        // XXX
                        // need to be more specific about illegal arg
                        throw new IllegalArgumentException();
                    } catch (StringIndexOutOfBoundsException e) {
                        String rest  = s.substring(i);
                        sb.append(rest);
                        if (rest.length()==2)
                            i++;
                        }

                        break;
                default:
                    sb.append(c);
                    break;
            }
        }

        return sb.toString();
    }


    /**
     *
     * Reconstructs the URL the client used to make the request,
     * using information in the <code>HttpServletRequest</code> object.
     * The returned URL contains a protocol, server name, port
     * number, and server path, but it does not include query
     * string parameters.
     * 
     * <p>Because this method returns a <code>StringBuffer</code>,
     * not a string, you can modify the URL easily, for example,
     * to append query parameters.
     *
     * <p>This method is useful for creating redirect messages
     * and for reporting errors.
     *
     * @param req	a <code>HttpServletRequest</code> object
     *			containing the client's request
     * 
     * @return		a <code>StringBuffer</code> object containing
     *			the reconstructed URL
     */
    public static StringBuffer getRequestURL (HttpServletRequest req) {
        StringBuffer url = new StringBuffer();
        String scheme = req.getScheme ();
        int port = req.getServerPort ();
        String urlPath = req.getRequestURI();

        //String		servletPath = req.getServletPath ();
        //String		pathInfo = req.getPathInfo ();

        url.append (scheme);		// http, https
        url.append ("://");
        url.append (req.getServerName ());
        if ((scheme.equals ("http") && port != 80)
        || (scheme.equals ("https") && port != 443)) {
            url.append (':');
            url.append (req.getServerPort ());
        }
        //if (servletPath != null)
        //    url.append (servletPath);
        //if (pathInfo != null)
        //    url.append (pathInfo);
        url.append(urlPath);

        return url;
    }
}

⏎ javax/servlet/http/HttpUtils.java

Or download all of them as a single archive file:

File name: javax.servlet-api-4.0.1-sources.jar
File size: 203006 bytes
Release date: 2018-04-20
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