/** * Returns <code>Boolean.TRUE</code> if the boolean value of * <code>args.get(0)</code> is false, and <code>Boolean.FALSE</code> otherwise. * The boolean value is calculated as if by the XPath <code>boolean</code> * function. * * @param context the context at the point in the * expression where the function is called * @param args a single element list * * @return <code>Boolean.TRUE</code> if the boolean value of * <code>obj</code> is false, and <code>Boolean.FALSE</code> otherwise * * @throws FunctionCallException if <code>args</code> does not have exactly one argument */ public Object call(Context context, List args) throws FunctionCallException { if (args.size() == 1) { return evaluate( args.get(0), context.getNavigator() ); } throw new FunctionCallException( "not() requires one argument." ); }