com.go.tea.parsetree
Class RelationalExpression

java.lang.Object
  |
  +--com.go.tea.parsetree.Node
        |
        +--com.go.tea.parsetree.Expression
              |
              +--com.go.tea.parsetree.BinaryExpression
                    |
                    +--com.go.tea.parsetree.BinaryLogicalExpression
                          |
                          +--com.go.tea.parsetree.RelationalExpression

All Implemented Interfaces:

java.lang.Cloneable, Logical, java.io.Serializable

public class RelationalExpression

extends BinaryLogicalExpression

RelationalExpression defines seven operations, "==", "!=", "<", ">", "<=" ">=" and "isa". The type of a RelationalExpression is a Boolean, set by a type checker if there are no errors.

Operator returned is one of Token.EQ, Token.NE, Token.LT, Token.GT, Token.LE, Token.GE or Token.ISA.

Version:

25 , 9/07/00

Author:

Brian S O'Neill

See Also:

Serialized Form

Inner classes inherited from class com.go.tea.parsetree.Expression

Expression.Conversion

Constructor Summary

RelationalExpression(SourceInfo info, Token operator, Expression left, Expression right)

RelationalExpression(SourceInfo info, Token operator, Expression left, TypeName typeName)
Used to construct an "isa" RelationalExpression.

Method Summary

java.lang.Object	accept(NodeVisitor visitor) Every subclass of Node must override this method with the following: return visitor.visit(this).
TypeName	getIsaTypeName() Only applies if token is "isa".
Expression	getRightExpression()
boolean	isExceptionPossible() Returns true if an exception can be thrown while executing this Expression.

Methods inherited from class com.go.tea.parsetree.BinaryLogicalExpression

convertTo

Methods inherited from class com.go.tea.parsetree.BinaryExpression

clone, getLeftExpression, getOperator, setLeftExpression, setRightExpression, setType

Methods inherited from class com.go.tea.parsetree.Expression

convertTo, getConversionChain, getInitialType, getType, getValue, isValueKnown, setInitialType

Methods inherited from class com.go.tea.parsetree.Node

getSourceInfo, toString

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

RelationalExpression

public RelationalExpression(SourceInfo info,
                            Token operator,
                            Expression left,
                            Expression right)

RelationalExpression

public RelationalExpression(SourceInfo info,
                            Token operator,
                            Expression left,
                            TypeName typeName)

Used to construct an "isa" RelationalExpression.

Method Detail

accept

public java.lang.Object accept(NodeVisitor visitor)

Description copied from class: Node

Every subclass of Node must override this method with the following: return visitor.visit(this).

Overrides:

accept in class Expression

Following copied from class: com.go.tea.parsetree.Node

Parameters:

visitor - A visitor of this Node

Returns:

Node The Node returned by the visitor

See Also:

NodeVisitor

isExceptionPossible

public boolean isExceptionPossible()

Description copied from class: Expression

Returns true if an exception can be thrown while executing this Expression. By default, returns true only if a type conversion could cause an exception.

Overrides:

isExceptionPossible in class BinaryExpression

getRightExpression

public Expression getRightExpression()

Overrides:

getRightExpression in class BinaryExpression

Returns:

null if an "isa" RelationalExpression

getIsaTypeName

public TypeName getIsaTypeName()

Only applies if token is "isa".