Java URL Query Build getQueryMap(String urlString)

Description

Parses a URLs query parameters into a Map for easier parsing of options.

License

Open Source License

Parameter

Parameter	Description
urlString	The URL to attempt to map the query parameters for

Return

Null if an invalid URL is passed in, otherwise a Map containing all the keys and values contained in the URL query parameters

Declaration

public static Map<String, String> getQueryMap(String urlString)

Method Source Code


//package com.java2s;
/*//  ww w .java  2s  .  co m
 * The MIT License (MIT)
 * Copyright (c) 2016 Fernando Barillas (FBis251)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy of this software and
 * associated documentation files (the "Software"), to deal in the Software without restriction,
 * including without limitation the rights to use, copy, modify, merge, publish, distribute,
 * sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all copies or substantial
 * portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT
 * NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
 * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 */

import java.net.MalformedURLException;
import java.net.URI;
import java.net.URL;
import java.util.HashMap;
import java.util.Map;

public class Main {
    /**
     * Parses a URLs query parameters into a Map for easier parsing of options.
     * For example, a URL http://example.com?one=1&amp;two=true
     * would return the map:
     * K: "one", V: "1"
     * K: "two", V: "true"
     *
     * @param urlString The URL to attempt to map the query parameters for
     * @return Null if an invalid URL is passed in, otherwise a Map containing all the keys and
     * values contained in the URL query parameters
     */
    public static Map<String, String> getQueryMap(String urlString) {
        return getQueryMap(getUrlObject(urlString));
    }

    /**
     * @param url The URL to attempt to map the query parameters for
     * @return Null if an invalid URL is passed in, otherwise a Map containing all the keys and
     * values contained in the URL query parameters
     * @see #getQueryMap(String)
     */
    public static Map<String, String> getQueryMap(URL url) {
        if (url == null)
            return null;
        return buildQueryMap(url.getQuery());
    }

    /**
     * @param uri The URI to attempt to map the query parameters for
     * @return Null if an invalid URI is passed in, otherwise a Map containing all the keys and
     * values contained in the URI query parameters
     * @see #getQueryMap(String)
     */
    public static Map<String, String> getQueryMap(URI uri) {
        if (uri == null)
            return null;
        return buildQueryMap(uri.getQuery());
    }

    /**
     * Verifies that a URL contains a certain TLD or a subdomain of the passed in TLD. Additionally
     * the passed-in urlString will be converted to a valid URL object
     *
     * @param urlString  A url to attempt to convert to a URL object
     * @param baseDomain The TLD to match with no subdomain prefix or trailing slash, example:
     *                   imgur.com
     * @return A URL Object representation of the passed in urlString
     */
    public static URL getUrlObject(String urlString, String baseDomain) {
        URL url = getUrlObject(urlString);
        if (url == null)
            return null;

        String domain = url.getHost();
        if (domain.equals(baseDomain) || domain.endsWith("." + baseDomain)) {
            return url;
        }

        return null;
    }

    /**
     * Get a URL Object from a passed in String
     *
     * @param urlString The String to attempt to parse as a URL
     * @return A URL representation if the passed in String is a valid URL, null otherwise
     */
    public static URL getUrlObject(String urlString) {
        try {
            return new URL(urlString);
        } catch (MalformedURLException ignored) {
        }
        return null;
    }

    private static Map<String, String> buildQueryMap(String query) {
        if (query == null)
            return null;

        String[] params = query.split("&");
        Map<String, String> map = new HashMap<>();
        for (String param : params) {
            String[] currentParam = param.split("=");
            if (currentParam.length != 2)
                continue;
            String name = currentParam[0];
            String value = currentParam[1];
            map.put(name, value);
        }
        return map;
    }
}