headerbase.java

OSGI这是一个中间件,与UPNP齐名,是用于移植到嵌入式平台之上

/*
 * Copyright (c) 2003, KNOPFLERFISH project
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials
 *   provided with the distribution.
 *
 * - Neither the name of the KNOPFLERFISH project nor the names of its
 *   contributors may be used to endorse or promote products derived
 *   from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */

package org.knopflerfish.bundle.http;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Dictionary;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Iterator;
import java.util.Locale;
import java.util.StringTokenizer;

import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletResponse;

public class HeaderBase {

    // private constants

    private static final int NO_VALUE = Integer.MIN_VALUE;

    // protected constants

    protected static final String CONNECTION_HEADER_KEY = "Connection";

    protected static final String CONTENT_TYPE_HEADER_KEY = "Content-Type";

    protected static final String CONTENT_LENGTH_HEADER_KEY = "Content-Length";

    protected static final String COOKIE_HEADER_KEY = "Cookie";

    protected static final String DATE_HEADER_KEY = "Date";

    protected static final String LANGUAGE_HEADER_KEY = "Accept-Language";

    protected static final String HOST_HEADER_KEY = "Host";

    // private fields

    private final Dictionary headers = new Hashtable();

    private String contentType = null;

    private int contentLength = NO_VALUE;

    private final Dictionary cookies = new Hashtable();

    private final ArrayList locales = new ArrayList(3);

    // constructors

    HeaderBase() {
    }

    // public methods

    public void init(ServletInputStreamImpl in) throws HttpException,
            IOException {
        parseHeaders(in);
    }

    public void destroy() {

        HttpUtil.removeAll(headers);

        contentType = null;
        contentLength = NO_VALUE;

        HttpUtil.removeAll(cookies);
        locales.clear();
    }

    public String getHeader(String name) {

        ArrayList values = (ArrayList) headers.get(name.toLowerCase());
        if (values == null)
            return null;
        Iterator i = values.iterator();
        if (i.hasNext())
            return (String) i.next();
        return null;
    }

    public Enumeration getHeaders(String name) {

        ArrayList values = (ArrayList) headers.get(name.toLowerCase());
        if (values == null)
            return HttpUtil.EMPTY_ENUMERATION;

        return HttpUtil.enumeration(values);
    }

    public Dictionary getHeaders() {
        return headers;
    }

    public String getContentType() {

        if (contentType == null)
            parseContentType();

        return contentType;
    }

    public int getContentLength() {

        if (contentLength == NO_VALUE)
            contentLength = parseContentLength();

        return contentLength;
    }

    public Dictionary getCookies() {

        if (cookies.isEmpty())
            parseCookies();

        return cookies;
    }

    public Enumeration getLocales() {

        if (locales.isEmpty())
            parseLocales();

        return HttpUtil.enumeration(locales);
    }

    // private methods

    private void parseHeaders(ServletInputStreamImpl in) throws HttpException,
            IOException {

        String name = null;
        String value = null;
        ArrayList values = null;

        String line = in.readLine();
        while (line != null && line.length() > 0) {

            char c = line.charAt(0);
            if (c == ' ' || c == '\t') { // continued header value

                // check not first line
                if (!(name != null && value != null && values != null))
                    throw new HttpException(HttpServletResponse.SC_BAD_REQUEST);

                // set concatenated header value
                value = value + line.substring(1);
                values.remove(values.size() - 1);
                values.add(value);

            } else {

                int index = line.indexOf(": ");

                // get header name
                name = line.substring(0, index).trim().toLowerCase();

                // get header value
                values = (ArrayList) headers.get(name);
                if (values == null)
                    values = new ArrayList();

                // add header value to vector
                value = line.substring(index + 2);
                values.add(value);
                headers.put(name, values);
            }

            // read next line
            line = in.readLine();
        }
    }

    private void parseContentType() {

        contentType = getHeader(CONTENT_TYPE_HEADER_KEY);
        // encoding = getHeader(CONTENT_TYPE_HEADER_KEY);
    }

    private int parseContentLength() {

        String headerValue = getHeader(CONTENT_LENGTH_HEADER_KEY);

        if (headerValue == null)
            return -1;

        try {
            return Integer.parseInt(headerValue);
        } catch (NumberFormatException nfe) {
            return -1;
        }
    }

    private void parseCookies() {

        Enumeration cookieEnumeration = getHeaders(COOKIE_HEADER_KEY);
        while (cookieEnumeration.hasMoreElements()) {
            String cookieString = (String) cookieEnumeration.nextElement();

            int version = 0;
            String previousToken = "";
            boolean isValue = false;
            Cookie cookie = null;

            StringTokenizer st = new StringTokenizer(cookieString, "=;,", true);
            while (st.hasMoreElements()) {
                String token = ((String) st.nextElement()).trim();

                if (token.equals("="))
                    isValue = true;
                else if (";,".indexOf(token) != -1)
                    isValue = false;
                else {
                    if (isValue) {
                        if (token.charAt(0) == '\"') {
                            int index = token.indexOf('\"', 1);
                            if (index == -1)
                                break;
                            token = token.substring(1, index);
                        }
                        if (previousToken.equals("$Version")) {
                            try {
                                version = Integer.parseInt(token);
                            } catch (Exception e) {
                                break;
                            }
                        } else if (previousToken.equals("$Path")) {
                            if (cookie == null)
                                break;
                            cookie.setPath(token);
                        } else if (previousToken.equals("$Domain")) {
                            if (cookie == null)
                                break;
                            cookie.setDomain(token);
                        } else {
                            cookie = new Cookie(previousToken, token);
                            cookie.setVersion(version);
                            cookies.put(cookie.getName(), cookie);
                        }
                    } else
                        previousToken = token;
                }
            }

        }
    }

    private void parseLocales() {

        Enumeration localeEnumeration = getHeaders(LANGUAGE_HEADER_KEY);
        while (localeEnumeration.hasMoreElements()) {
            // String localeString = (String) localeEnumeration.nextElement();

            // NYI: parse locale strings
        }

        if (locales.size() == 0)
            locales.add(Locale.getDefault());
    }

} // HeaderBase