Java URL Create createURL(String spec, URLStreamHandlerFactory urlHandlerFactory)

Description

Tries to parse a String as an URL.

License

Open Source License

Parameter

Parameter	Description
spec	the <code>String</code> to parse
urlHandlerFactory	an URL stream handler factory to use

Return

an URL if the parsing is successful

Declaration

public static URL createURL(String spec,
        URLStreamHandlerFactory urlHandlerFactory) 

Method Source Code

//package com.java2s;
/*//w ww  .j  a va  2s .  com
 * JasperReports - Free Java Reporting Library.
 * Copyright (C) 2001 - 2014 TIBCO Software Inc. All rights reserved.
 * http://www.jaspersoft.com
 *
 * Unless you have purchased a commercial license agreement from Jaspersoft,
 * the following license terms apply:
 *
 * This program is part of JasperReports.
 *
 * JasperReports 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 3 of the License, or
 * (at your option) any later version.
 *
 * JasperReports 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 JasperReports. If not, see <http://www.gnu.org/licenses/>.
 */

import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLStreamHandler;
import java.net.URLStreamHandlerFactory;

public class Main {
    /**
     * Tries to parse a <code>String</code> as an URL.
     * 
     * @param spec the <code>String</code> to parse
     * @param urlHandlerFactory an URL stream handler factory to use
     * @return an URL if the parsing is successful
     * @see #getURLHandler(String, URLStreamHandlerFactory)
     * @see #getURLHandlerFactory(URLStreamHandlerFactory)
     */
    public static URL createURL(String spec,
            URLStreamHandlerFactory urlHandlerFactory) {
        URLStreamHandler handler = getURLHandler(spec, urlHandlerFactory);
        URL url;
        try {
            if (handler == null) {
                url = new URL(spec);
            } else {
                url = new URL(null, spec, handler);
            }
        } catch (MalformedURLException e) {
            url = null;
        }
        return url;
    }

    /**
     * Returns an URL stream handler for an URL specified as a <code>String</code>.
     * 
     * @param spec the <code>String</code> to parse as an URL
     * @param urlHandlerFact an URL stream handler factory
     * @return an URL stream handler if one was found for the protocol of the URL
     * @see #getURLHandlerFactory(URLStreamHandlerFactory)
     */
    public static URLStreamHandler getURLHandler(String spec,
            URLStreamHandlerFactory urlHandlerFact) {
        URLStreamHandlerFactory urlHandlerFactory = urlHandlerFact;//getURLHandlerFactory(urlHandlerFact);

        URLStreamHandler handler = null;
        if (urlHandlerFactory != null) {
            String protocol = getURLProtocol(spec);
            if (protocol != null) {
                handler = urlHandlerFactory
                        .createURLStreamHandler(protocol);
            }
        }
        return handler;
    }

    private static String getURLProtocol(String urlSpec) {
        String protocol = null;

        String spec = urlSpec.trim();
        int colon = spec.indexOf(':');
        if (colon > 0) {
            String proto = spec.substring(0, colon);
            if (protocolValid(proto)) {
                protocol = proto;
            }
        }

        return protocol;
    }

    private static boolean protocolValid(String protocol) {
        int length = protocol.length();
        if (length < 1) {
            return false;
        }

        if (!Character.isLetter(protocol.charAt(0))) {
            return false;
        }

        for (int i = 1; i < length; ++i) {
            char c = protocol.charAt(i);
            if (!(Character.isLetterOrDigit(c) || c == '+' || c == '-' || c == '.')) {
                return false;
            }
        }

        return true;
    }
}

Related

1. createURL(final String protocol, final String userInfo, final String host, final int port, final String path, final String query, final String ref)
2. createUrl(final String spec)
3. createURL(final String url)
4. createURL(String fileName)
5. createUrl(String spec)
6. createURL(String src, File basedir)
7. createURL(String str)
8. createURL(String url)
9. createURL(String url)