/* verifies that each of our registered parameters has a value, either given or default throws an exeption otherwise */ private void verify() throws Exception { for (Argument parameter : parameters.values()) { if (parameter.getValue() == null && parameter.getDefaultValue() == null) { throw new Exception( String.format("Argument '%s' is required. Please see usage.", parameter.name)); } } }
public Object getValue(String argumentName) { Object value = null; argumentName = argumentName.toLowerCase(); if (parameters.containsKey(argumentName)) { Argument argument = parameters.get(argumentName); value = argument.getValue(); if (value == null) { String defaultValue = argument.getDefaultValue(); try { value = argument.getHandler().tryArgument(defaultValue); } catch (Exception e) { } } } return value; }
/* Tries each handler for the given parameter and returns a success boolean */ private boolean parseKV(String key, String value) throws Exception { boolean success = false; // must have a registered handler; see registerArgumentHandler() if (!parameters.containsKey(key)) { throw new Exception(key + " is not a valid argument"); } Argument arg = parameters.get(key); // don't allow dupes if (arg.getValue() != null) { throw new Exception("Duplicate arguments: " + key); } try { // handler returns null if it can't handle the argument // it can throw an exception if the argument is an unacceptable value Object param = arg.getHandler().tryArgument(value); if (param != null) { arg.setValue(param); success = true; } } catch (Exception e) { throw new Exception("Bad argument value for '" + key + "': " + e.getMessage()); } return success; }