org.expressionj.expr

Class ExprDecrement

java.lang.Object

org.expressionj.model.AbstractExpression

org.expressionj.expr.ExprDecrement

All Implemented Interfaces:

java.lang.Cloneable, Expression, ExpressionType

public class ExprDecrement
extends AbstractExpression

Represent a decrement (--) expression.

Field Summary

Fields inherited from class org.expressionj.model.AbstractExpression

block, root

Fields inherited from interface org.expressionj.model.ExpressionType

STRUCT_ARRAY, STRUCT_SCALAR, STRUCT_STRUCTURE, TYPE_BOOL, TYPE_DYNAMIC, TYPE_FLOAT, TYPE_INTEGER, TYPE_NUMERIC, TYPE_STRING, TYPE_UNDEF

Constructor Summary

Constructors

Constructor and Description
ExprDecrement(Expression root)

Method Summary

Modifier and Type	Method and Description
java.lang.Object	clone()
java.lang.Object	eval() Evaluate the expression.
float	evalAsFloat() Evaluate the expression as a float.
int	evalAsInt() Evaluate the expression as an int.
java.lang.String	getExpressionName() Return the expression name.
short	getResultStructure() Return the structure of the result for the expression.
short	getResultType() Return the type of the result for the expression.
Variable	getVariable()
Variable	getVariable(java.lang.String varName) Return a variable declared by the expression.
java.util.Map<java.lang.String,Variable>	getVariables() Return the variables used by this expression.
void	setVariable(Variable var)

Methods inherited from class org.expressionj.model.AbstractExpression

evalAsBoolean, getParentBlock, getRoot, setParentBlock, setRoot

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.expressionj.model.Expression

getExpression, getLocalVariable, getLocalVariables, getVariable, getVariables, hasVariable, hasVariable, removeVariable

Constructor Detail

ExprDecrement

public ExprDecrement(Expression root)

Method Detail

clone

public java.lang.Object clone()
                       throws java.lang.CloneNotSupportedException

Specified by:

clone in interface Expression

Specified by:

clone in class AbstractExpression

Throws:

java.lang.CloneNotSupportedException

getExpressionName

public java.lang.String getExpressionName()

Description copied from interface: Expression

Return the expression name.

Returns:

the expression name

setVariable

public void setVariable(Variable var)

getVariable

public Variable getVariable()

evalAsInt

public final int evalAsInt()

Description copied from interface: Expression

Evaluate the expression as an int. The result of the evaluation will be the same as Expression.eval(), but the evaluation engine will be able to optimize the computation by knwoing that the result is an int (primitive valeus are cached internally).

Specified by:

evalAsInt in interface Expression

Overrides:

evalAsInt in class AbstractExpression

Returns:

the result as an int

evalAsFloat

public final float evalAsFloat()

Description copied from interface: Expression

Evaluate the expression as a float. The result of the evaluation will be the same as Expression.eval(), but the evaluation engine will be able to optimize the computation by knwoing that the result is a float (primitive valeus are cached internally).

Specified by:

evalAsFloat in interface Expression

Overrides:

evalAsFloat in class AbstractExpression

Returns:

the result as a float

eval

public java.lang.Object eval()
                      throws java.lang.ArithmeticException

Description copied from interface: Expression

Evaluate the expression.

Returns:

the result

Throws:

java.lang.ArithmeticException

getResultStructure

public short getResultStructure()

Description copied from interface: Expression

Return the structure of the result for the expression. The structure can be:

• ExpressionType.STRUCT_SCALAR: a scalar value
• ExpressionType.STRUCT_ARRAY: an array value

Returns:

he structure of the result for the expression

getResultType

public short getResultType()

Description copied from interface: Expression

Return the type of the result for the expression. The type can be:

• ExpressionType.TYPE_INTEGER: integer
• ExpressionType.TYPE_FLOAT: float
• ExpressionType.TYPE_NUMERIC: integer or float value. The runtime actual type may depend on the expression arguments
• ExpressionType.TYPE_STRING: string
• ExpressionType.TYPE_DYNAMIC: dynamic type. The runtime actual type may depend on the expression arguments
• ExpressionType.TYPE_UNDEF: undefined type. The default type, characteristic of an error if entountered.

Returns:

the type of the result for the expression

getVariables

public java.util.Map<java.lang.String,Variable> getVariables()

Description copied from interface: Expression

Return the variables used by this expression. Note that this method will not return any internal variables declared by the expression. For example, in the following expression: int c=a+b, only "a" and "b" will be returned.

Returns:

the variables used by this expression

getVariable

public Variable getVariable(java.lang.String varName)

Description copied from interface: Expression

Return a variable declared by the expression.

Parameters:

varName - the variable name

Returns:

the variable