CommandLine Parser : Console « Development Class « Java
CommandLine Parser
/*
* This file is part of the AusStage Utilities Package
*
* The AusStage Utilities Package is free software: you can redistribute
* it and/or modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation, either version 3 of the
* License, or (at your option) any later version.
*
* The AusStage Utilities Package is distributed in the hope that it will
* be useful, but WITHOUT ANY WARRANTY; without even the implied warranty
* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with the AusStage Utilities Package.
* If not, see <http://www.gnu.org/licenses/>.
*/
//package au.edu.ausstage.utils;
// import additional packages
import java.util.HashMap;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
* A class of methods useful when reading arguments from the command line
*/
public class CommandLineParser {
// declare private class level variables
private HashMap<String,String> arguments;
/**
* Class constructor
* Parse the command line arguments such that any argument starting with '-' or '--' is assumed to be a key
* The following argument if it doesn't start with a '-' or '--' is assumed to be a value
*
* @param args the array of command line arguments
*/
public CommandLineParser(String[] args) {
// initialise the arguments map
arguments = new HashMap<String, String>();
// declare other helper variables
String key = null;
String value = null;
int index = 0;
// loop through the list of arguments
for(int i = 0; i < args.length; i++) {
// look for a key
if (args[i].startsWith("--")) {
// this is a key that starts with a --
key = args[i].substring(2);
} else if(args[i].startsWith("-")) {
// this is a key that start with a -
key = args[i].substring(1);
} else {
// this is a key that starts with nothing as a value
arguments.put(args[i], null);
// end this iteration of the loop
continue;
}
// look for a value
// does the key contain an = character?
index = key.indexOf('=');
if(index == -1) {
// no - use the next argument as the value
// is there a value to use
if((i + 1) < args.length) {
// yes - but does the value look like a key?
if(args[i + 1].charAt(0) != '-') {
// no - so add the key and value
arguments.put(key, args[i + 1]);
// increment the count so we don't process this value again
i++;
} else {
// yes - so add just the key
arguments.put(args[i], null);
}
} else {
// no - so just add the key
arguments.put(args[i], null);
}
} else {
// yes - extract the value from the key
value = key.substring(index + 1);
// fix the key
key = key.substring(0, index);
// add the key and value to the map
arguments.put(key, value);
}
} // end loop
} // end class constructor
/**
* get the value of the first key found in the list of arguments
*
* @param key the key to lookup
* @return value the value of the arguments
*/
public String getValue(String key) {
// check to ensure the key is valid
if(InputUtils.isValid(key)) {
// return the key if found or null if it isn't
return arguments.get(key);
}
// invalid key so return null
return null;
} // end getValue method
/**
* check to see if a key exists in the list arguments
*
* @param key the key to lookup
* @return value the value of the arguments
*/
public boolean containsKey(String key) {
// check to ensure the key is valid
if(InputUtils.isValid(key)) {
if(arguments.get(key) != null) {
return true;
} else {
return false;
}
}
// invalid key so return null
return false;
} // end containsKey method
} // end class definition
class InputUtils {
/**
* check to ensure a parameter value is valid
*
* @param value the parameter value
*
* @return true if, and only if, the parameter is valid
*/
public static boolean isValid(String value) {
// check on the parameter value
if(value == null) {
return false;
} else {
value = value.trim();
if(value.equals("") == true) {
return false;
}
}
// passed validation
return true;
} // end the isValid method
/**
* check to ensure a parameter is valid and is from a list
*
* @param value the parameter value
* @param list the list of allowed values
*
* @return true if, and only if, the parameter is valid
*/
public static boolean isValid(String value, String[] list) {
// check if it is not null first
if(isValid(value) == false) {
return false;
}
// check the value against the list
boolean isValid = false;
for(int i = 0; i < list.length; i++) {
if(list[i].equals(value)) {
isValid = true;
}
}
return isValid;
} // end the isValid method with list
/**
* check to ensure a parameter value is valid
*
* @param value the parameter value
*
* @return true if, and only if, the parameter is valid
*/
public static boolean isValidInt(String value) {
if(isValid(value) == false) {
return false;
}
// can we parse the value as a int?
try {
Integer.parseInt(value);
} catch (java.lang.NumberFormatException ex) {
// nope
return false;
}
// if we get this far everything is OK
return true;
} // end the isValid method
/**
* check to ensure a parameter value is valid
*
* @param value the parameter value
* @param minimum the minimum allowed value
*
* @return true if, and only if, the parameter is valid
*/
public static boolean isValidInt(int value, int minimum) {
if(value >= minimum) {
return false;
} else {
return true;
}
} // end the isValid method
/**
* check to ensure a parameter value is valid
*
* @param value the parameter value
* @param minimum the minimum allowed value
* @param maximum the maximum allowed value
*
* @return true if, and only if, the parameter is valid
*/
public static boolean isValidInt(int value, int minimum, int maximum) {
if(value >= minimum && value <= maximum) {
return true;
} else {
return false;
}
} // end the isValid method
/**
* check to ensure a parameters value is valid
*
* @param date the date to check in the format yyyy-mm-dd
*/
public static boolean isValidDate(String date) {
// define the pattern
Pattern pattern = Pattern.compile("^\\d{4}-\\d{2}-\\d{2}$");
Matcher matcher = pattern.matcher(date);
if(matcher.find() == true) {
return true;
} else {
return false;
}
}
/**
* A method to take an array of values and return them in a comma delimited list
*
* @param values the array of values to process
*
* @return the string representation of the list
*/
public static String arrayToString(String[] values) {
return java.util.Arrays.toString(values).replaceAll("[\\]\\[]", "");
} // end the arrayToString method
/**
* A method to ensure an array of strings represent an array of integers
*
* @param values the array of strings
*
* @return true if, and only if, all of the values pass inspection
*/
public static boolean isValidArrayInt(String[] values) {
// declare helper variables
boolean status = true;
// loop through all of the elements in the array
for(int i = 0; i < values.length; i++) {
if(isValidInt(values[i]) == false) {
// this value isn't valid
status = false;
// exit the loop early
i = values.length;
}
}
// return the status
return status;
} // end isValidArrayInt method
} // end class definition
