What is the difference between comparable and Comparator Java?
KEY DIFFERENCES: Comparable in Java is an object to compare itself with another object, whereas Comparator is an object for comparing different objects of different classes. Comparable provides compareTo() method to sort elements in Java whereas Comparator provides compare() method to sort elements in Java.
What is the difference between a comparable and a Comparator?
1) Comparable provides a single sorting sequence. In other words, we can sort the collection on the basis of a single element such as id, name, and price. The Comparator provides multiple sorting sequences. In other words, we can sort the collection on the basis of multiple elements such as id, name, and price etc.
Can you explain why Java has both a comparable interface and a Comparator interface?
Logically, Comparable interface compares “this” reference with the object specified and Comparator in Java compares two different class objects provided. If any class implements Comparable interface in Java then collection of that object either List or Array can be sorted automatically by using Collections.
What is the difference between compareTo and compare with?
compareTo() is from the Comparable interface. compare() is from the Comparator interface. Both methods do the same thing, but each interface is used in a slightly different context. The Comparable interface is used to impose a natural ordering on the objects of the implementing class.
What are the differences between the comparable interface and the Comparator interface?
Comparable and comparator both are an interface that can be used to sort the elements of the collection. Comparator interface sort collection using two objects provided to it, whereas comparable interface compares” this” refers to the one objects provided to it.
What is comparable interface in Java?
The Java Comparable interface, java. lang. 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.
What is the difference between comparable interface and comparator interface?
What is comparator interface?
Method 2: Using comparator interface- Comparator interface is used to order the objects of a user-defined class. This interface is present in java. util package and contains 2 methods compare(Object obj1, Object obj2) and equals(Object element). Using a comparator, we can sort the elements based on data members.
What are three differences between Comparator and comparable?
sort(List, Comparator) method can be used to sort the collection of Comparator type objects. Comparable provides single sorting sequence. The comparator provides a multiple sorting sequence. Comparable interface belongs to java.
Why use a Comparator if we already have comparable?
Comparable should be used when you compare instances of the same class. Comparator can be used to compare instances of different classes. Comparable is implemented by the class which needs to define a natural ordering for its objects. For example, String implements Comparable.
How does a comparable and Comparator work internally?
In Java, Comparable and Comparator are used for sorting collection of objects. java. lang. Comparable is used to sort collection of same types(classes) like List, List, List, It means Comparable is like “I can compare myself with another object of same type”.
What is difference between writable comparable and writable Comparator?
In short, the type used as key in Hadoop must be a WritableComparable , while the type only used as value could be just a Writable . A Writable which is also Comparable. WritableComparables can be compared to each other, typically via Comparators.
What is the difference between comparator and comparative interface in Java?
Comparator interface belongs to java.util package while comparable belongs to java.lang package. Comparator interface sort collection using two objects provided to it, whereas comparable interface compares” this” refers to the one objects provided to it.
What is the difference between collectioncomparator and Comparable interface?
Comparator interface sort collection using two objects provided to it, whereas comparable interface compares” this” refers to the one objects provided to it. Collection.sort (List) method can be used to sort the collection of Comparable type objects.
What is the difference between comparable and Comparator interface sorting?
Comparable is meant for objects with natural ordering which means the object itself must know how it is to be ordered. For example Roll Numbers of students. Whereas, Comparator interface sorting is done through a separate class.
What is a comparable object in Java?
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. Suppose we wish to sort a list of Movies based on year of release.