Comparable Interface

Objects that have an ordering are compared using the compareTo() method.

3. This is enough to put a collection in order.


"apple", "orange", "plum".

This is the order that compareTo() would place the strings.

Comparable<String> Interface

StringA is regarded as less than StringB if StringA would be proceed StringB in a dictionary. For example,

Evaluates to
Negative Integer
Negative Integer
Positive Integer

Only the sign of the returned integer matters if the return value is not zero. The magnitude of a returned integer does not signify anything.

Memory Aide: think of this as subtraction.

apple - orange will be negative.
apple - apple will be zero.
orange - apple will be positive.

Question 3:

Examine the following:

    String myPet = "Fido" ; String stray = "Rex" ; if ( myPet.compareTo( stray ) < 0 ) System.out.println( "Good Dog" ); else System.out.println( "Bad Dog" );

What is printed?