com.solacesystems.common.util.expression

Class Expression

java.lang.Object

com.solacesystems.common.util.expression.Expression

All Implemented Interfaces:

ExpressionArgument

public class Expression
extends Object
implements ExpressionArgument

This class represents a generic postfix (also known as reverse polish) expression stack.

Constructor Summary

Constructors

Constructor and Description
Expression() Expression constructor.
Expression(Expression expression) Copy constructor to clone the passed expression stack.

Method Summary

Methods

Modifier and Type	Method and Description
void	add(ExpressionArgument arg) Adds a new expression argument to the stack.
ExpressionArgument	evaluate(Expression expression, Object input) This method is called when an argument in the expression stack is evaluated.
ExpressionArgument	evaluate(Object input) Evaluate the expression with the provided input.
ExpressionArgument	get(int index) Gets the expression argument at the specified index.
int	size() Gets the size of the stack.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

Expression

public Expression()

Expression constructor. Create a new expression stack.

Expression

public Expression(Expression expression)

Copy constructor to clone the passed expression stack.

Parameters:

expression - Expression stack to clone.

Method Detail

add

public void add(ExpressionArgument arg)

Adds a new expression argument to the stack.

Parameters:

arg - The new ExpressionArgument to add.

get

public ExpressionArgument get(int index)

Gets the expression argument at the specified index.

Parameters:

index - Index of the expression argument to return.

Returns:

ExpressionArgument at the given index.

size

public int size()

Gets the size of the stack.

Returns:

The size of the stack.

evaluate

public ExpressionArgument evaluate(Object input)

Evaluate the expression with the provided input.

Parameters:

input - Input to be evaluated.

Returns:

The last item on the stack is returned.

evaluate

public ExpressionArgument evaluate(Expression expression,
                          Object input)

Description copied from interface: ExpressionArgument

This method is called when an argument in the expression stack is evaluated. The method Expression#evaluate(Object input) is used to evaluate the entire stack.

Specified by:

evaluate in interface ExpressionArgument

Parameters:

expression - The expression stack the argument is in.

input - The input argument to the expression stack.

Returns:

The resultant value to push back on the stack.

See Also:

Expression

toString

public String toString()

Overrides:

toString in class Object