The ArrayList Class and the enum Keyword - Learning Java Through Games - page 147

}

public void flip() {
face = (bias < Math . random ( ) ) ? Face .HEADS : Face . TAILS ; // true is
heads

}

private Currency getRandomCoinValue () {
double randomNumber = Math . random( ) ;
if (randomNumber < 0.25) {
return Currency .PENNY;
if (randomNumber < 0.5) {
return Currency .NICKEL;
if (randomNumber

< 0.75) {

return Currency .DIME;
return C u r r e n c y . QUARTER ;

}

public String toString() {
return value+ " that is " +face ;

}

public int getValue () {
return value . getValue() ;

}

public boolean isHeads () {
return ( f a c e == F a c e . HEADS ) ;

}

}

If you create a penny that is heads and try to print it, the toString method will return
“PENNY that is HEADS”. As you can see, we have eliminated the switch statement. Next,
let us examine in details the enum construct.
enum Currency

{
PENNY ( 1 ) , NICKEL ( 5 ) , DIME ( 1 0 ) , QUARTER ( 2 5 ) ;
private int value ;

private Currency( int value) {

this . value = value ;
} public int getValue () {
return value ;

}

}

The definition is similar to that of a class. The only difference is that the first line defines
a set of constants. A number that each constant maps to can be specified in parentheses. If
this mapping is specified, then you must define a variable of this type (in our case int )and
a constructor that sets the value of the variable. Note that the constructor must be private.
Alternatively, one can specify an enum type as follows.
enum Currency {