com.whitestein.lsps.lang.ast

Class ConstantExpression

java.lang.Object

com.whitestein.lsps.lang.ast.ASTRangeImpl

com.whitestein.lsps.lang.ast.ASTNodeImpl

com.whitestein.lsps.lang.ast.Expression

com.whitestein.lsps.lang.ast.ConstantExpression

All Implemented Interfaces:

ASTInfo, ASTNode, ASTRange

public final class ConstantExpression
extends Expression

Expression representing a constant. Only constants of type corresponding to SimpleType except SimpleType.OBJECT are allowed.

Author:

rba

Field Summary

Fields

Modifier and Type	Field and Description
static ConstantExpression	FALSE Predefined constant with false value.
static ConstantExpression	NULL Predefined constant with null value.
static ConstantExpression	TRUE Predefined constant with true values.

Fields inherited from interface com.whitestein.lsps.lang.ast.ASTInfo

EMPTY

Constructor Summary

Constructors

Constructor and Description
ConstantExpression(ASTInfo info, java.lang.Object constant) Creates new instance of ConstantExpression.
ConstantExpression(ASTInfo info, java.lang.Object constant, Type type) Creates new instance of ConstantExpression.

Method Summary

Modifier and Type	Method and Description
<T,E extends java.lang.Throwable> T	accept(ExpressionVisitor<T,E> visitor) Accepts visitor.
protected java.lang.Object	basicInterpret(Interpreter interpreter, InterpreterStackTrace stackTrace) Interpret expression.
java.lang.Object	getConstant() Returns the constant.
java.lang.Object	getParseTimeConstant() Returns the value of the expression determined in parse time.
boolean	isParseTimeConstant() Returns true if the value of the expression is known in parse time.

Methods inherited from class com.whitestein.lsps.lang.ast.Expression

createANTLRParser, doInterpret, evalCondition, evaluateToExpressions, executeCompiled, getCompiled, getDebugLine, getIdentifierAst, getPrimaryRange, getPropertySelectorRange, getRange, getResultExpression, getResultExpressions, getType, interpret, interpretInCurrentNamespace, isCreatingNonModuleContextObjects, requiresNewNamespace, setCompiled, showInFullText, showInSurroundingText, showInText, toExpressions

Methods inherited from class com.whitestein.lsps.lang.ast.ASTNodeImpl

getFullText, getLine, getNodeText, getText, toString

Methods inherited from class com.whitestein.lsps.lang.ast.ASTRangeImpl

contains, getBeginIndex, getEndIndex, getLength

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.whitestein.lsps.lang.ast.ASTNode

getFullText, getLine, getNodeText, getText

Methods inherited from interface com.whitestein.lsps.lang.ast.ASTRange

contains, getBeginIndex, getEndIndex, getLength

Field Detail

NULL

public static final ConstantExpression NULL

Predefined constant with null value.

FALSE

public static final ConstantExpression FALSE

Predefined constant with false value.

TRUE

public static final ConstantExpression TRUE

Predefined constant with true values.

Constructor Detail

ConstantExpression

public ConstantExpression(ASTInfo info,
                          java.lang.Object constant)

Creates new instance of ConstantExpression.

Parameters:

info -

constant -

Throws:

java.lang.NullPointerException - if constant is null

java.lang.IllegalArgumentException - if constant type is invalid

ConstantExpression

public ConstantExpression(ASTInfo info,
                          java.lang.Object constant,
                          Type type)

Creates new instance of ConstantExpression.

Parameters:

info -

constant -

type -

Throws:

java.lang.NullPointerException - if constant or type is null

java.lang.IllegalArgumentException - if constant is not assignable to type

Method Detail

getConstant

public java.lang.Object getConstant()

Returns the constant.

Returns:

the constant

isParseTimeConstant

public boolean isParseTimeConstant()

Description copied from class: Expression

Returns true if the value of the expression is known in parse time. E.g. constant literals, enumerations, types (without free types).

Overrides:

isParseTimeConstant in class Expression

Returns:

true if the expression value is known during parsing

See Also:

Expression.getParseTimeConstant()

getParseTimeConstant

public java.lang.Object getParseTimeConstant()

Description copied from class: Expression

Returns the value of the expression determined in parse time. The default implementation throws UnsupportedOperationException. Subclasses, which return true when Expression.isParseTimeConstant() is called, should override this method.

Overrides:

getParseTimeConstant in class Expression

Returns:

the value determined in parse time

See Also:

Expression.isParseTimeConstant()

accept

public <T,E extends java.lang.Throwable> T accept(ExpressionVisitor<T,E> visitor)
                                           throws E extends java.lang.Throwable

Description copied from class: Expression

Accepts visitor.

Specified by:

accept in class Expression

Returns:

the result of visit

Throws:

E

E extends java.lang.Throwable

basicInterpret

protected java.lang.Object basicInterpret(Interpreter interpreter,
                                          InterpreterStackTrace stackTrace)

Description copied from class: Expression

Interpret expression.

Specified by:

basicInterpret in class Expression

Returns:

result of interpretation