001/**
002 *
003 * Licensed to the Apache Software Foundation (ASF) under one or more
004 * contributor license agreements.  See the NOTICE file distributed with
005 * this work for additional information regarding copyright ownership.
006 * The ASF licenses this file to You under the Apache License, Version 2.0
007 * (the "License"); you may not use this file except in compliance with
008 * the License.  You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.kahadb.util;
019
020import java.util.ArrayList;
021
022/**
023 * Support utility that can be used to set the properties on any object
024 * using command line arguments.
025 * 
026 * @author <a href="http://hiramchirino.com">Hiram Chirino</a>
027 */
028public class CommandLineSupport {
029        
030        /**
031         * Sets the properties of an object given the command line args.
032         * 
033         * if args contains: --ack-mode=AUTO --url=tcp://localhost:61616 --persistent 
034         * 
035         * then it will try to call the following setters on the target object.
036         * 
037         * target.setAckMode("AUTO");
038         * target.setURL(new URI("tcp://localhost:61616") );
039         * target.setPersistent(true);
040         * 
041         * Notice the the proper conversion for the argument is determined by examining the 
042         * setter argument type.  
043         * 
044         * @param target the object that will have it's properties set
045         * @param args the command line options
046         * @return any arguments that are not valid options for the target
047         */
048        static public String[] setOptions(Object target, String []args) {
049                ArrayList rc = new ArrayList();
050                
051                for (int i = 0; i < args.length; i++) {
052                        if( args[i] == null )
053                                continue;
054                        
055                        if( args[i].startsWith("--") ) {
056                                
057                                // --options without a specified value are considered boolean flags that are enabled.
058                                String value="true";
059                                String name = args[i].substring(2);
060                                
061                                // if --option=value case
062                                int p = name.indexOf("=");
063                                if( p > 0 ) {
064                                        value = name.substring(p+1);
065                                        name = name.substring(0,p);
066                                }
067                                
068                                // name not set, then it's an unrecognized option
069                                if( name.length()==0 ) {
070                                        rc.add(args[i]);
071                                        continue;
072                                }
073                                
074                                String propName = convertOptionToPropertyName(name);
075                                if( !IntrospectionSupport.setProperty(target, propName, value) ) {                                      
076                                        rc.add(args[i]);
077                                        continue;
078                                }
079                        } else {
080                            rc.add(args[i]);
081                        }
082                        
083                }
084                
085                String r[] = new String[rc.size()];
086                rc.toArray(r);
087                return r;
088        }
089
090        /**
091         * converts strings like: test-enabled to testEnabled
092         * @param name
093         * @return
094         */
095        private static String convertOptionToPropertyName(String name) {
096                String rc="";
097                
098                // Look for '-' and strip and then convert the subsequent char to uppercase
099                int p = name.indexOf("-");
100                while( p > 0 ) {
101                        // strip
102                        rc += name.substring(0, p);
103                        name = name.substring(p+1);
104                        
105                        // can I convert the next char to upper?
106                        if( name.length() >0 ) {
107                                rc += name.substring(0,1).toUpperCase();
108                                name = name.substring(1);
109                        }
110                        
111                        p = name.indexOf("-");
112                }
113                return rc+name;
114        }
115}