Computer Applications
Answer
Java Library classes are a set of predefined classes in the form of packages that are provided to the programmer as part of Java installation. Library classes simplify the job of programmers by providing built-in methods for common and non-trivial tasks like taking input from user, displaying output to user, etc. For example, System class in java.lang package of Java Library classes provides the print() and println() methods for displaying output to user.
Related Questions
Predict the output of the following code snippet:
char ch='B', char chr=Character.toLowerCase(ch); int n=(int)chr-10; System.out.println((char)n+"\t"+chr);Give the output of the following code:
String P = "20", Q ="19"; int a = Integer.parseInt(P); int b = Integer.valueOf(Q); System.out.println(a+""+b);Primitive data types are built in data types which are a part of the wrapper classes. These wrapper classes are encapsulated in the java.lang package. Non primitive datatypes like Scanner class are a part of the utility package for which an object needs to be created.
(a) To which package the Character and Boolean classes belong?
(b) Write the statement to access the Scanner class in the program.
Assertion (A): Integer class can be used in the program without calling a package.
Reason (R): It belongs to the default package java.lang.
- Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A)
- Both Assertion (A) and Reason (R) are true and Reason (R) is not a correct explanation of Assertion(A)
- Assertion (A) is true and Reason (R) is false
- Assertion (A) is false and Reason (R) is true