URI.java

/*
 * This file is part of the OWASP Proxy, a free intercepting proxy library.
 * Copyright (C) 2008-2010 Rogan Dawes <rogan@dawes.za.net>
 * 
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to:
 * The Free Software Foundation, Inc., 
 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

package org.owasp.proxy.model;

import java.net.URISyntaxException;

public class URI {

    private String input = null, scheme = null, host = null, path = null,
            query = null, fragment = null;

    private int port = -1;

    public URI(String url) throws URISyntaxException {
        input = url;
        parseHierarchical();
    }

    private void parseHierarchical() throws URISyntaxException {
        int length = input.length();
        int start = 0, end;
        end = scan(start, ":");
        if (end == length)
            throw new URISyntaxException(input,
                    "No ':' found extracting the scheme");
        scheme = input.substring(start, end);

        if (end > length - 3 || !"://".equals(input.substring(end, end + 3)))
            throw new URISyntaxException(input, "Expected '://'", end);
        end = end + 3;

        start = end;
        end = scan(start, ":/");
        if (end == length)
            throw new URISyntaxException(input,
                    "Unexpected end of URI looking for port or path");
        host = input.substring(start, end);

        if (input.charAt(end) == ':') { // get the port
            start = end;
            end = scan(start, "/");
            if (end == length)
                throw new URISyntaxException(input,
                        "Unexpected end of URI looking for path");
            try {
                port = Integer.parseInt(input.substring(start + 1, end));
                if (port < 1 || port > 65535)
                    throw new URISyntaxException(input, "port out of range",
                            start);
            } catch (NumberFormatException nfe) {
                URISyntaxException use = new URISyntaxException(input,
                        "Illegal port specification!", start);
                use.initCause(nfe);
                throw use;
            }
        }

        start = end;
        end = scan(start, "?#");
        path = input.substring(start, end);
        if (end == length)
            return;
        if (input.charAt(end) == '?') { // get the query
            start = end;
            end = scan(start, "#");
            query = input.substring(start, end);
        }
        if (end == length)
            return;

        if (input.charAt(end) == '#') { // get the fragment
            start = end;
            fragment = input.substring(start);
        }
    }

    // Scan forward from the given start position. Stop at the first char
    // in the stop string (in which case the index of the preceding char is
    // returned), or the end of the input string (in which case the length
    // of the input string is returned).
    private int scan(int start, String stop) {
        int p = start;
        int end = input.length();
        while (p < end) {
            char c = input.charAt(p);
            if (stop.indexOf(c) >= 0)
                break;
            p++;
        }
        return p;
    }

    public String getScheme() {
        return scheme;
    }

    public String getHost() {
        return host;
    }

    public int getPort() {
        return port;
    }

    public String getPath() {
        return path;
    }

    public String getQuery() {
        return query;
    }

    public String getFragment() {
        return fragment;
    }

    public String getResource() {
        StringBuilder buff = new StringBuilder(path);
        if (query != null)
            buff.append(query);
        if (fragment != null)
            buff.append(fragment);
        return buff.toString();
    }

    public String toString() {
        StringBuilder buff = new StringBuilder();
        buff.append(scheme).append("://");
        buff.append(host);
        if (port > -1)
            buff.append(":").append(port);
        buff.append(path);
        if (query != null)
            buff.append(query);
        if (fragment != null)
            buff.append(fragment);
        return buff.toString();
    }

}