sjm.imperative
Class IfCommand

java.lang.Object
  |
  +--sjm.imperative.Command
        |
        +--sjm.imperative.IfCommand

public class IfCommand

extends Command

This command mimics a normal "if" statement, such as:

     if (x > 7) {
         // body to execute if condition is true
     } else {
         // body to execute if condition is false
     }
 

Field Summary

protected BooleanTerm	condition
protected Command	elseCommand
protected Command	ifCommand

Constructor Summary

IfCommand(BooleanTerm condition, Command ifCommand)
Construct an "if" command from the given condition and command.

IfCommand(BooleanTerm condition, Command ifCommand, Command elseCommand)
Construct an "if" command from the given condition and command.

Method Summary

void	execute() Execute this "if" command.
java.lang.String	toString() Returns a string description of this if command.

Methods inherited from class java.lang.Object

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

Field Detail

condition

protected BooleanTerm condition

ifCommand

protected Command ifCommand

elseCommand

protected Command elseCommand

Constructor Detail

IfCommand

public IfCommand(BooleanTerm condition,
                 Command ifCommand)

Construct an "if" command from the given condition and command.

Parameters:

condition - the condition to check

ifCommand - the command to execute if the condition evaluates to true

IfCommand

public IfCommand(BooleanTerm condition,
                 Command ifCommand,
                 Command elseCommand)

Construct an "if" command from the given condition and command.

Parameters:

condition - the condition to check

ifCommand - the command to execute if the condition evaluates to true

elseCommand - the command to execute if the condition evaluates to false

Method Detail

execute

public void execute()

Execute this "if" command. Evaluate the condition. If it is true, execute this object's ifCommand. Otherwise, execute the elseCommand, which may be a NullCommand object.

Overrides:

execute in class Command

toString

public java.lang.String toString()

Returns a string description of this if command.

Overrides:

toString in class java.lang.Object

Returns:

a string description of this if command