Trail: Getting Started

Questions and Exercises: Getting Started


Question 1: When you compile a program written in the Java programming language, the compiler converts the human-readable source file into platform-independent code that a Java Virtual Machine can understand. What is this platform-independent code called?

Question 2: Which of the following is not a valid comment:

a. /** comment */
b. /* comment */
c. /* comment
d. // comment

Question 3: What is the first thing you should check if you see the following error at runtime:

Exception in thread "main" java.lang.NoClassDefFoundError:

Question 4: What is the correct signature of the main method?

Question 5: When declaring the main method, which modifier must come first, public or static?

Question 6: What parameters does the main method define?


Exercise 1: Change the program so that it displays Hola Mundo! instead of Hello World!.

Exercise 2: You can find a slightly modified version of HelloWorldApp here:

The program has an error. Fix the error so that the program successfully compiles and runs. What was the error?

Check your answers.

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