Java MCQs on Syntax and Semantics

Which of the following correctly describes Syntax in Java?

• The meaning of a syntactically correct program.

• The structure of statements or elements in a programming language.

• The algorithm used to check errors in a program.

• The way objects are stored in memory.

What is wrong with the following code? int[] arr = [1, 2, 3];

• Syntax error

• Semantic error

• No error

• Runtime error

What is the semantic error in the following code? String a = new String("hello"); String b = new String("hello"); if (a == b) { System.out.println("Equal"); } else { System.out.println("Not Equal"); }

• Syntax error because == cannot be used with String.

• Semantic error because == compares references instead of string content.

• No error, the program runs correctly.

• Runtime error because a and b are not initialized.

To identify syntax errors in Java, you need to:

• Understand the program's algorithm.

• Check the code against rules in The Java Language Specification.

• Run the program and check the output.

• Use knowledge of memory and resource management.

What is wrong with the following code? int x = 10 System.out.println(x);

• Syntax error due to missing semicolon.

• Semantic error because x is not initialized.

• Syntax error because System.out.println is invalid.

• No error.

What is the semantic error in the following code? int sum = 0; for (int i = 1; i <= 5; i++) { sum = i; } System.out.println(sum);

• Syntax error due to incorrect for loop format.

• Semantic error because sum does not accumulate i values.

• Runtime error because sum exceeds int limits.

• No error.

In Java, the {x} notation in grammar rules indicates:

• Exactly one occurrence of x.

• Zero or one occurrence of x.

• Zero or more occurrences of x.

• A sequence of x elements concatenated together.

What is the value of the number 12_34_56 in Java?

• Invalid, causes a syntax error.

• 123456

• 12

• 56

Is the following code syntactically correct? int a, b = 5, c

• Correct syntax.

• Syntax error due to missing semicolon.

• Syntax error because c is not initialized.

• Syntax error because int cannot be used for multiple variables.

In the Syntax Tree for int x = 10;, which component is the UnannType?

• x

• 10

• int

• =