conditional statement patterns
Are there any patterns for use of 'if statements' or 'switch statements' ?
I want to know if there is a better way of writing this for example.....
privatevoid actionOptions(String cmd){
if (cmd.equals("Pause")){
simulationStatusHolder = SIMULATION_PAUSE;
stopGo.setLabel("Go");
notify();
}elseif (cmd.equals("Go")){
simulationStatusHolder = SIMULATION_GO;
stopGo.setLabel("Pause");
notify();
}elseif (cmd.equals("Start From Scratch")){
simulationStatusHolder = SIMULATION_RESTART;
stopGo.setLabel("Pause");
notify();
}elseif (cmd.equals("End the World")){
owner.close();
}
}
[1438 byte] By [
Jenskia] at [2007-10-2 7:32:17]
> Are there any patterns for use of 'if statements' or
> 'switch statements' ?
Yes, the command pattern.
public class DynamicSwitch {
public abstract class AbstractCase { public void execute() { System.err.println( this.getClass().getName() ) ; } } ;
public class CaseAA extends AbstractCase { } ;
public class CaseBB extends AbstractCase { } ;
public class CaseCC extends AbstractCase { } ;
java.util.HashMap cases = new java.util.HashMap() ;
/** Creates a new instance of DynamicSwitch */
public DynamicSwitch() {
// load these names from a properties file
// and use a class factory to construct them.
cases.put( "AA" ,new CaseAA() ) ;
cases.put( "BB" ,new CaseBB() ) ;
cases.put( "CC" ,new CaseCC() ) ;
}
public void execute(String key) {
AbstractCase abstractCase = (AbstractCase) cases.get( key ) ;
abstractCase.execute() ;
}
/**
* @param args the command line arguments
*/
public static void main(String[] args) {
// TODO code application logic here
DynamicSwitch instance = new DynamicSwitch() ;
instance.execute( "AA" ) ;
instance.execute( "BB" ) ;
instance.execute( "CC" ) ;
}
}
