What is the Java comparable interface?
Java Comparable interface is used to order the objects of the user-defined class. This interface is found in java. lang package and contains only one method named compareTo(Object). It provides a single sorting sequence only, i.e., you can sort the elements on the basis of single data member only.
Which objects are comparable in Java?
Comparable , represents an object which can be compared to other objects. For instance, numbers can be compared, strings can be compared using alphabetical comparison etc. Several of the built-in classes in Java implements the Java Comparable interface.
How does comparable work in Java?
The compare() method in Java compares two class specific objects (x, y) given as parameters. It returns the value: 0: if (x==y) -1: if (x < y)
Is comparable A interface?
The Comparable interface defines the compareTo method used to compare objects. If a class implements the Comparable interface, objects created from that class can be sorted using Java’s sorting algorithms.
How do I make Java comparable?
To make an object comparable, the class must implement the Comparable interface. negative , if this object is less than the supplied object. zero , if this object is equal to the supplied object. positive , if this object is greater than the supplied object.
What is comparable method?
The basic premise of the comparables approach is that an equity’s value should bear some resemblance to other equities in a similar class. For a stock, this can simply be determined by comparing a firm to its key rivals, or at least those rivals that operate similar businesses.
Is comparable a functional interface?
Answer: Yes, comparable is a functional interface. It declares a single abstract method, compareTo ().
What is difference between compare and compareTo in Java?
compareTo() is a method of the interface Comparable, so it is used to compare THIS instance to another one. compare() is a method of the interface Comparator, so it is used to compare two different instances of another class with each other.
What is a comparable object?
A comparable object is capable of comparing itself with another object. The class itself must implements the java. lang. Comparable interface to compare its instances. Consider a Movie class that has members like, rating, name, year.
Is comparable a functional interface in Java?
How to implement comparable in Java?
You will have to implement just one method, “compareTo.” This ordering of any type is called natural ordering, and the implemented “compareTo” method is called the natural comparison method. Here in this Comparable in Java Example article, we will look at the different examples on comparable in java.
What is the use of compareTo in Java?
This interface is a member of the Java Collections Framework. compareTo(T o) Compares this object with the specified object for order. Method Detail compareTo int compareTo(T o) Compares this object with the specified object for order.
What is compareTo method in public interface?
public interface Comparable> This interface imposes a total ordering on the objects of each class that implements it. This ordering is referred to as the class’s natural ordering , and the class’s compareTo method is referred to as its natural comparison method .
What is the natural ordering of comparable in Java?
Virtually all Java core classes that implement Comparable have natural orderings that are consistent with equals. One exception is java.math.BigDecimal, whose natural ordering equates BigDecimal objects with equal values and different precisions (such as 4.0 and 4.00).