B4 - The Comparable Interface

An interface, in general, is a list of what things?

• methods and variables

• classes and constants

• methods

• methods and constants

Say that you are writing a class Book and wish it to implement the Comparable<Book> interface. What method must Book contain?

• int compareTo( Book other )

• int compareTo( Object other )

• Book compareTo( Object other )

• boolean compareTo( T other )

What is the value of "zebra".compareTo("emu")

• a negative integer

• 0

• a positive integer

• unpredictable

What is the value of (new Integer(5)).compareTo( new Integer(8) )

• a negative integer

• 0

• a positive integer

• unpredictable

If the objects of a class are arranged into their natural order, then if object L is left of object R what is true?

• L.compareTo(R) is positive

• L.compareTo(R) is negative

• L.compareTo(R) is zero

• R.compareTo(L) is negative

If X.compareTo(Y) is positive, then which of the following is true?

• Y.compareTo(X) is positive

• Y.compareTo(X) is negative

• Y.compareTo(X) is zero

• Y.compareTo(X) is unknown

If X.equals(Y) is true, then which of the following is true for most classes that implement Comparable?

• X.compareTo(Y) is negative

• X.compareTo(Y) is zero

• X.compareTo(Y) is positive

• Nothing can be said.

What is "ZURICH".compareTo("cairo")

• a negative integer

• zero

• a positive integer

• unknown

What is "pit viper".compareTo("pit")

• a negative integer

• zero

• a positive integer

• unknown

What algorithm quickly searches an ordered array?

• binary search

• linear search

• random search

• ordered search