Computer Applications
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);
Answer
Output of the above code is:
2019
Working
Both Integer.parseInt() and Integer.valueOf() methods convert a string into integer. Integer.parseInt() returns an int value that gets assigned to a. Integer.valueOf() returns an Integer object (i.e. the wrapper class of int). Due to auto-boxing, Integer object is converted to int and gets assigned to b. So a becomes 20 and b becomes 19. 2019 is printed as the output.
Related Questions
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
A student is trying to convert the string present in x to a numerical value, so that he can find the square root of the converted value. However the code has an error. Name the error (syntax / logical / runtime). Correct the code so that it compiles and runs correctly.
String x= "25"; int y=Double.parseDouble(x); double r=Math.sqrt(y); System.out.println(r);The method to convert a String to double is:
- String.toDouble()
- Double.Parsedouble()
- Double.parseDouble(String)
- Double.parseDouble()