001/**
002 * Copyright 2005-2015 The Kuali Foundation
003 *
004 * Licensed under the Educational Community License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.opensource.org/licenses/ecl2.php
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.kuali.rice.krad.util;
017
018import org.apache.commons.codec.EncoderException;
019import org.apache.commons.codec.net.URLCodec;
020import org.apache.commons.lang.StringUtils;
021import org.apache.log4j.Logger;
022
023import java.util.Properties;
024
025/**
026 * Provides utility methods for re/building URLs.
027 * 
028 * @author Kuali Rice Team (rice.collab@kuali.org)
029 */
030public class UrlFactory {
031    private static Logger LOG = Logger.getLogger(UrlFactory.class);
032
033    /**
034     * Creates a new URL by taking the given URL and appending the parameter names and values from the given Properties instance to
035     * it. Note: parameter names must be non-blank; parameter values must be non-null.
036     * 
037     * @param baseUrl the URL string used as the basis for reconstruction
038     * @param params Properties instance containing the desired parameters and their values
039     * @throws IllegalArgumentException if the given url is null or empty
040     * @throws IllegalArgumentException if the given Properties instance is null
041     * @throws IllegalArgumentException if a parameter name is null or empty, or a parameter value is null
042     * @throws RuntimeException if there is a problem encoding a parameter name or value into UTF-8
043     * @return a newly-constructed URL string which has the given parameters and their values appended to it
044     */
045    private static URLCodec urlCodec = new URLCodec("UTF-8");
046    
047    public static String parameterizeUrl(String baseUrl, Properties params) {
048        baseUrl = StringUtils.trim(baseUrl);
049        if (StringUtils.isEmpty(baseUrl)) {
050            throw new IllegalArgumentException("invalid (blank) base URL");
051        }
052        if (params == null) {
053            throw new IllegalArgumentException("invalid (null) Properties");
054        }
055
056
057        StringBuffer ret = new StringBuffer(baseUrl);
058        // Only start with ? if it has not been added to the url
059        String delimiter = (ret.indexOf("?") == -1) ? "?" : "&";
060        for ( Object key : params.keySet() ) {
061            String paramName = StringUtils.trim( (String)key );
062            String paramValue = params.getProperty(paramName);
063            ret.append( delimiter );
064            if (StringUtils.isEmpty(paramName)) {
065                throw new IllegalArgumentException("invalid (blank) paramName");
066            }
067            if (paramValue == null) {
068                ret.append( paramName );
069                ret.append( "=" );
070            } else {
071                try {
072                    ret.append( paramName );
073                    ret.append( "=" );
074                    ret.append( urlCodec.encode(paramValue) );
075                } catch ( EncoderException ex ) {
076                    LOG.error("Unable to encode parameter name or value: " + paramName + "=" + paramValue, ex);
077                    throw new RuntimeException( "Unable to encode parameter name or value: " + paramName + "=" + paramValue, ex );
078                }
079            }
080            delimiter = "&";
081        }
082
083        return ret.toString();
084    }
085
086    public static String encode( String value ) {
087        try {
088            return urlCodec.encode(value);
089        } catch ( EncoderException ex ) {
090            throw new RuntimeException( "Unable to encode value: " + value, ex );
091        }
092    }
093}