Interface:
Interface is a reference type in Java, which contains a collection of abstract methods.
An interface needs to the follow certain conditions such as:
- One cannot instantiate an interface.
- Interfaces do not contain any constructors.
- All methods present in the interface are abstracts.
- An interface does not contain any instance field.
- An interface cannot be extended by a class.
Comparable Interface:
A comparable interface is a generic interface that defines the compareTo() method that is used for comparing objects.
Example:
//java langauage package for comaprable interface
package java.lang
//comparable interface definition
public interface Comparable <E>
{
//use of compareTo to compare objects
public integer compareTo(E o);
}
The compareTo() method determines the order of this object with the specified object “o” and returns a negative integer, zero or positive integer, if this object is less than, equal to or greater than object “o”.
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Introduction to Java Programming and Data Structures, Comprehensive Version, Student Value Edition (11th Edition)
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