/** Gets an instance of an expression from the factory. */ private Expression getExpression( Class<? extends Expression> expressionClass) { return ExpressionFactory.getExpressionFactory().createExpression( expressionClass, getConf()); }
/** Gets a named expression from the factory. */ private Expression getExpression(String expressionName) { return ExpressionFactory.getExpressionFactory().getExpression( expressionName, getConf()); }
/** Asks the factory whether an expression is recognized. */ private boolean isExpression(String expressionName) { return ExpressionFactory.getExpressionFactory() .isExpression(expressionName); } }
/** * Get an instance of the requested expression * * @param expressionName * name of the command to lookup * @param conf * the Hadoop configuration * @return the {@link Expression} or null if the expression is unknown */ Expression getExpression(String expressionName, Configuration conf) { if (conf == null) throw new NullPointerException("configuration is null"); Class<? extends Expression> expressionClass = expressionMap .get(expressionName); Expression instance = createExpression(expressionClass, conf); return instance; }
/** Register the expressions with the expression factory. */ private static void registerExpressions(ExpressionFactory factory) { for (Class<? extends Expression> exprClass : EXPRESSIONS) { factory.registerExpression(exprClass); } }
/** Asks the factory whether an expression is recognized. */ private boolean isExpression(String expressionName) { return ExpressionFactory.getExpressionFactory() .isExpression(expressionName); } }
/** * Creates an instance of the requested {@link Expression} class. * * @param expressionClassname * name of the {@link Expression} class to be instantiated * @param conf * the Hadoop configuration * @return a new instance of the requested {@link Expression} class */ Expression createExpression(String expressionClassname, Configuration conf) { try { Class<? extends Expression> expressionClass = Class.forName( expressionClassname).asSubclass(Expression.class); return createExpression(expressionClass, conf); } catch (ClassNotFoundException e) { throw new IllegalArgumentException("Invalid classname " + expressionClassname); } } }
/** Register the expressions with the expression factory. */ private static void registerExpressions(ExpressionFactory factory) { for (Class<? extends Expression> exprClass : EXPRESSIONS) { factory.registerExpression(exprClass); } }
/** Gets an instance of an expression from the factory. */ private Expression getExpression( Class<? extends Expression> expressionClass) { return ExpressionFactory.getExpressionFactory().createExpression( expressionClass, getConf()); }
/** Gets a named expression from the factory. */ private Expression getExpression(String expressionName) { return ExpressionFactory.getExpressionFactory().getExpression( expressionName, getConf()); }
/** Asks the factory whether an expression is recognized. */ private boolean isExpression(String expressionName) { return ExpressionFactory.getExpressionFactory() .isExpression(expressionName); } }
ArrayList<Expression> primaries = new ArrayList<Expression>(); for (Class<? extends Expression> exprClass : EXPRESSIONS) { Expression expr = factory.createExpression(exprClass, null); if (expr.isOperator()) { operators.add(expr);
/** Register the expressions with the expression factory. */ private static void registerExpressions(ExpressionFactory factory) { for (Class<? extends Expression> exprClass : EXPRESSIONS) { factory.registerExpression(exprClass); } }
/** Gets an instance of an expression from the factory. */ private Expression getExpression( Class<? extends Expression> expressionClass) { return ExpressionFactory.getExpressionFactory().createExpression( expressionClass, getConf()); }
/** Gets a named expression from the factory. */ private Expression getExpression(String expressionName) { return ExpressionFactory.getExpressionFactory().getExpression( expressionName, getConf()); }
/** Asks the factory whether an expression is recognized. */ private boolean isExpression(String expressionName) { return ExpressionFactory.getExpressionFactory() .isExpression(expressionName); } }
/** * Get an instance of the requested expression * @param expressionName name of the command to lookup * @param conf the hadoop configuration * @return the {@link Expression} or null if the expression is unknown */ public Expression getExpression(String expressionName, Configuration conf) { if (conf == null) throw new NullPointerException("configuration is null"); Class<? extends Expression> expressionClass = expressionMap.get(expressionName); Expression instance = createExpression(expressionClass, conf); return instance; }