import java.awt.Choice;
...
Choice flavour = new Choice();

// adding possible choices
flavour.add( "strawberry" );
flavour.add( "chocolate" );
flavour.add( "vanilla" );

// setting the selection
flavour.select( 0 );
flavour.select( "strawberry" );

// detecting the selection
String choice = flavour.getSelectedItem();
int which = flavour.getSelectedIndex();