java 13 interview questions and answers

Are True And False Keywords

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The values true and false are not keywords. In Core Java, “true” and “false” are keywords used to represent boolean literals. These keywords are part of the Java programming language and are used to denote the boolean values true and false, respectively. For example: java boolean isTrue = true; boolean isFalse = false; Here, “true” and “false” are used … Read more

What Are E And PI

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E is the base of the natural logarithm and PI is mathematical value pi. In Core Java, E and PI typically refer to the constants Math.E and Math.PI defined in the java.lang.Math class. Math.E: This constant represents the mathematical constant “e,” which is the base of the natural logarithm. It is approximately equal to 2.71828. java double eValue … Read more

What Classes of Exceptions May be Thrown by a Throw Statement

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A throw statement may throw any expression that may be assigned to the Throwable type. In Java, the throw statement is used to explicitly throw an exception. When you use the throw statement, you typically throw an instance of a class that extends either Throwable, which is the base class for all exceptions and errors, or one … Read more

What is The Set Interface

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The Set interface provides methods for accessing the elements of a finite mathematical set. Sets do not allow duplicate elements. The Set interface in Java is a part of the Java Collections Framework and is part of the java.util package. It extends the Collection interface and represents a collection of unique elements. Unlike a List, a Set … Read more

If an Object is Garbage Collected, Can it Become Reachable Again

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Once an object is garbage collected, it ceases to exist. It can no longer become reachable again. No, once an object has been garbage collected in Java, it cannot become reachable again. Garbage collection is the process by which the Java Virtual Machine (JVM) automatically identifies and removes objects that are no longer reachable or … Read more