Java URL Query Parse parseQueryString(String queryString)

Description

parse Query String

License

Apache License

Declaration

public static Map<String, String[]> parseQueryString(String queryString) 

Method Source Code

//package com.java2s;
/**/*  w w  w  .jav a  2  s .c o  m*/
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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
 * <p/>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p/>
 * 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.
 */

import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;

public class Main {
    public static Map<String, String[]> parseQueryString(String queryString) {
        Map<String, String[]> map = new HashMap<String, String[]>();
        if (queryString != null && !queryString.isEmpty()) {
            StringTokenizer parser = new StringTokenizer(queryString, "&?;=", true);
            String name = null;
            String value = null;
            while (parser.hasMoreTokens()) {
                String token = parser.nextToken();
                String ttoken = token.trim();
                if (ttoken.length() == 1) {
                    char c = ttoken.charAt(0);
                    switch (c) {
                    case '&':
                    case '?':
                    case ';':
                        addQueryStringParam(map, name, value);
                        name = null;
                        value = null;
                        continue;
                    case '=':
                        if (name == null) {
                            name = "";
                            value = "";
                        } else if (name.isEmpty()) {
                            addQueryStringParam(map, name, value);
                            name = "";
                            value = "";
                        } else {
                            value = "";
                        }
                        continue;
                    }
                }
                if (name == null) {
                    name = token;
                } else {
                    value = token;
                }
            } // while
            if (name != null) {
                addQueryStringParam(map, name, value);
            }
        }
        return map;
    }

    static final void addQueryStringParam(final Map<String, String[]> map, String name, String value) {
        name = urlDecodeUtf8(name);
        value = urlDecodeUtf8(value);
        String[] values = map.get(name);
        if (values == null) {
            values = new String[] { value };
        } else {
            values = Arrays.copyOf(values, values.length + 1);
            values[values.length - 1] = value;
        }
        map.put(name, values);
    }

    private static final String urlDecodeUtf8(String s) {
        if (s != null) {
            try {
                s = URLDecoder.decode(s, "UTF-8");
            } catch (UnsupportedEncodingException e) {
                // Ignore it.
            }
        }
        return s;
    }
}

Related

1. parseQueryString(String path)
2. parseQueryString(String q, String enc)
3. parseQueryString(String query)
4. parseQueryString(String query)
5. parseQueryString(String query, boolean ignoreEmpty)
6. parseQueryString(String queryString)
7. parseQuerystring(String queryString)
8. parseQueryString(String queryString, Map params)
9. parseQueryStringEx(String queryString)