jrun.ejb.ejbql
Interface Operator

All Superinterfaces:

Element

All Known Implementing Classes:

OperatorBase

public interface Operator

extends Element

Behavior common to all EJBQL operators.

Author:

Enrique Duvos

Fields inherited from interface jrun.ejb.ejbql.Element

UNSPECIFIED_TRAVERSAL_ORDER

Method Summary

void	acceptOperatorExpression(Visitor visitor, OperatorExpression operatorExpr) In certain cases, an operator expression will delegate to an operator to perform the dispatch to the appropriate visitor method.
java.util.Iterator	getPrintStrings(java.util.Vector expressions) Return the operator strings to be used to print out the entire expression.
java.lang.String	getResultType(java.util.Vector expressions) The stringified version of the java Class type that results from applying the operator to the given set of expressions.
boolean	isBinary()
boolean	isFunction()
boolean	isNary()
boolean	isUnary()
boolean	operatesOn(java.util.Vector expressions) True if an operator can be applied to a given set of expressions.

Methods inherited from interface jrun.ejb.ejbql.Element

accept, getChildren

Method Detail

acceptOperatorExpression

public void acceptOperatorExpression(Visitor visitor,
                                     OperatorExpression operatorExpr)

In certain cases, an operator expression will delegate to an operator to perform the dispatch to the appropriate visitor method.

operatesOn

public boolean operatesOn(java.util.Vector expressions)

True if an operator can be applied to a given set of expressions. E.g. The Plus operator can only operate on exactly two expressions, each of which has numeric type.

getResultType

public java.lang.String getResultType(java.util.Vector expressions)

The stringified version of the java Class type that results from applying the operator to the given set of expressions.

getPrintStrings

public java.util.Iterator getPrintStrings(java.util.Vector expressions)

Return the operator strings to be used to print out the entire expression. Might be multiple strings, e.g. Expr1 BETWEEN Expr2 AND Expr3 print strings = { "BETWEEN", "AND" }

isUnary

public boolean isUnary()

isBinary

public boolean isBinary()

isNary

public boolean isNary()

isFunction

public boolean isFunction()