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What is Comparator in Java?

What is Comparator in Java?

Java Comparator is an interface for sorting Java objects. Invoked by “java. util. comparator,” Java Comparator compares two Java objects in a “compare(Object 01, Object 02)” format. Using configurable methods, Java Comparator can compare objects to return an integer based on a positive, equal or negative comparison.

What is Comparator and comparable in Java?

Comparable interface is used to sort the objects with natural ordering. Comparator in Java is used to sort attributes of different objects. Comparable interface compares “this” reference with the object specified. Comparator in Java compares two different class objects provided.

How do you compare two fields in Java?

reflect. Field is used to compare two field objects. This method compares two field objects and returns true if both objects are equal otherwise false. The two Field objects are considered equal if and only if when they were declared by the same class and have the same name and type.

What is the purpose of a comparator?

A comparator is used to compare a measurable quantity with a reference or standard such as two voltages or currents. It outputs a digital signal showing the results.

How does a comparator work?

A comparator circuit compares two voltages and outputs either a 1 (the voltage at the plus side) or a 0 (the voltage at the negative side) to indicate which is larger. Comparators are often used, for example, to check whether an input has reached some predetermined value.

How does a Comparator work?

Can we have 2 abstract methods in functional interface?

A functional interface is an interface that contains only one abstract method. They can have only one functionality to exhibit.

Why do we need Comparator?

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.

Can we compare two objects in Java?

In Java, the == operator compares that two references are identical or not. Whereas the equals() method compares two objects. Objects are equal when they have the same state (usually comparing variables). Objects are identical when they share the class identity.

How do you compare data types in Java?

To compare object types we need to implement the interface java. lang. Comparable with its single method int compareTo(T) . The result represents the natural order of our type, not just arithmetical comparability.