code: /*
   * 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
   *
   *     http://www.apache.org/licenses/LICENSE-2.0
   *
   * 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.
   */
  /*
   * $Id$
   */
  
  package org.apache.xalan.xsltc.cmdline.getopt; 
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.ListIterator;
  
  import org.apache.xalan.xsltc.compiler.util.ErrorMsg;
  
  
  /**
  * GetOpt is a Java equivalent to the C getopt() library function
  * discussed in man page getopt(3C). It provides command line
  * parsing for Java applications. It supports the most rules of the
  * command line standard (see man page intro(1)) including stacked
  * options such as '-sxm' (which is equivalent to -s -x -m); it
  * handles special '--' option that signifies the end of options.
  * Additionally this implementation of getopt will check for
  * mandatory arguments to options such as in the case of
  * '-d <file>' it will throw a MissingOptArgException if the 
  * option argument '<file>' is not included on the commandline.
  * getopt(3C) does not check for this. 
   * @author G Todd Miller 
  */
  public class GetOpt{
      public GetOpt(String[] args, String optString){
  	theOptions = new ArrayList();		 
  	int currOptIndex = 0; 
  	theCmdArgs = new ArrayList(); 
  	theOptionMatcher = new OptionMatcher(optString);
  	// fill in the options list
  	for(int i=0; i<args.length; i++){
  	    String token = args[i];
  	    int tokenLength = token.length();
  	    if(token.equals("--")){	    // end of opts
  	        currOptIndex = i+1;	    // set index of first operand
                  break;                      // end of options
  	    }
  	    else if(token.startsWith("-") && tokenLength == 2){ 
  		// simple option token such as '-s' found
  		theOptions.add(new Option(token.charAt(1)));	
  	    }
  	    else if(token.startsWith("-") && tokenLength > 2){
  		// stacked options found, such as '-shm'
  		// iterate thru the tokens after the dash and
  		// add them to theOptions list
  		for(int j=1; j<tokenLength; j++){
  		    theOptions.add(new Option(token.charAt(j)));
  		}
  	    }		
  	    else if(!token.startsWith("-")){
  		// case 1- there are not options stored yet therefore
  		// this must be an command argument, not an option argument
  		if(theOptions.size() == 0){
  		    currOptIndex = i;
  		    break;		// stop processing options
  		}
  		else {
  		    // case 2- 
  		    // there are options stored, check to see if
  		    // this arg belong to the last arg stored	
  		    int indexoflast=0;
  		    indexoflast = theOptions.size()-1;
  		    Option op = (Option)theOptions.get(indexoflast);
  		    char opLetter = op.getArgLetter();
  		    if(!op.hasArg() && theOptionMatcher.hasArg(opLetter)){
  		        op.setArg(token);
  		    }
  		    else{
  		        // case 3 - 
  		        // the last option stored does not take
  		        // an argument, so again, this argument
  		        // must be a command argument, not 
  		        // an option argument
  		        currOptIndex = i;
  		        break; 			// end of options 
  		    }
  	  	}
  	    }// end option does not start with "-"
  	} // end for args loop
  
          //  attach an iterator to list of options 
  	theOptionsIterator = theOptions.listIterator();
  
  	// options are done, now fill out cmd arg list with remaining args
  	for(int i=currOptIndex; i<args.length; i++){
  	    String token = args[i];
  	    theCmdArgs.add(token);
  	}
      }
  
  
      /**
      * debugging routine to print out all options collected
      */
      public void printOptions(){
  	for(ListIterator it=theOptions.listIterator(); it.hasNext();){
  	    Option opt = (Option)it.next();
  	    System.out.print("OPT =" + opt.getArgLetter());
  	    String arg = opt.getArgument();
  	    if(arg != null){
  	       System.out.print(" " + arg);
  	    }
  	    System.out.println();
  	}
      }
  
      /**
      * gets the next option found in the commandline. Distinguishes
      * between two bad cases, one case is when an illegal option
      * is found, and then other case is when an option takes an
      * argument but no argument was found for that option.
      * If the option found was not declared in the optString, then 
      * an IllegalArgumentException will be thrown (case 1). 
      * If the next option found has been declared to take an argument, 
      * and no such argument exists, then a MissingOptArgException
      * is thrown (case 2).
      * @return int - the next option found.
      * @throws IllegalArgumentException, MissingOptArgException. 
      */
      public int getNextOption() throws IllegalArgumentException, 
  	MissingOptArgException
      {
  	int retval = -1;
  	if(theOptionsIterator.hasNext()){
  	    theCurrentOption = (Option)theOptionsIterator.next();
  	    char c = theCurrentOption.getArgLetter();
  	    boolean shouldHaveArg = theOptionMatcher.hasArg(c);
  	    String arg = theCurrentOption.getArgument();
  	    if(!theOptionMatcher.match(c)) {
                  ErrorMsg msg = new ErrorMsg(ErrorMsg.ILLEGAL_CMDLINE_OPTION_ERR,
                                              new Character(c));
  		throw (new IllegalArgumentException(msg.toString()));
  	    }
  	    else if(shouldHaveArg && (arg == null)) {
                  ErrorMsg msg = new ErrorMsg(ErrorMsg.CMDLINE_OPT_MISSING_ARG_ERR,
                                              new Character(c));
  		throw (new MissingOptArgException(msg.toString()));
  	    }
  	    retval = c;
  	}
  	return retval;
      }
  
      /**
      * gets the argument for the current parsed option. For example,
      * in case of '-d <file>', if current option parsed is 'd' then
      * getOptionArg() would return '<file>'.
      * @return String - argument for current parsed option.
      */
      public String getOptionArg(){
  	String retval = null;
  	String tmp = theCurrentOption.getArgument();
  	char c = theCurrentOption.getArgLetter();
  	if(theOptionMatcher.hasArg(c)){
  	    retval = tmp;
  	}
  	return retval;	
      }
  
      /**
      * gets list of the commandline arguments. For example, in command
      * such as 'cmd -s -d file file2 file3 file4'  with the usage
      * 'cmd [-s] [-d <file>] <file>...', getCmdArgs() would return
      * the list {file2, file3, file4}.
      * @return String[] - list of command arguments that may appear
      *                    after options and option arguments.
      */
      public String[] getCmdArgs(){
  	String[] retval = new String[theCmdArgs.size()];
  	int i=0;
          for(ListIterator it=theCmdArgs.listIterator(); it.hasNext();){
              retval[i++] = (String)it.next();
          }
  	return retval;
      }
  
  
      private Option theCurrentOption = null;
      private ListIterator theOptionsIterator; 
      private List theOptions = null;
      private List theCmdArgs = null;
      private OptionMatcher theOptionMatcher = null;
  
      ///////////////////////////////////////////////////////////
      //
      //   Inner Classes
      //
      ///////////////////////////////////////////////////////////
  
      // inner class to model an option
      static class Option{
          private char theArgLetter;
          private String theArgument = null;
          public Option(char argLetter) { theArgLetter = argLetter; }
          public void setArg(String arg) { 
  	    theArgument = arg;
          }
          public boolean hasArg() { return (theArgument != null); } 
          public char getArgLetter() { return theArgLetter; }
          public String getArgument() { return theArgument; }
      } // end class Option
  
  
      // inner class to query optString for a possible option match,
      // and whether or not a given legal option takes an argument. 
      //  
      static class OptionMatcher{
          public OptionMatcher(String optString){
  	    theOptString = optString;	
          }
          public boolean match(char c){
  	    boolean retval = false;
  	    if(theOptString.indexOf(c) != -1){
  	        retval = true;
  	    }
  	    return retval;	
          }
          public boolean hasArg(char c){
  	    boolean retval = false;
  	    int index = theOptString.indexOf(c)+1; 
  	    if (index == theOptString.length()){
  	        // reached end of theOptString
  	        retval = false;
  	    }
              else if(theOptString.charAt(index) == ':'){
                  retval = true;
              }
              return retval;
          }
          private String theOptString = null;
      } // end class OptionMatcher
  }// end class GetOpt
      
  