To solve this question, the user needs to know that the given code is testing whether a string value is null or empty. They also need to know the syntax of if-else statements in Java.
Now, let's go through each option and explain why it is right or wrong:
A. null: This option is incorrect because the code checks if the string is null using the expression str == null
, which evaluates to false since str
is "null" (a non-null string literal).
B. zero: This option is incorrect because the code does not check if the string is empty using the expression str.length() == 0
. Instead, it tries to use an invalid syntax by placing an else block after the if block. This leads to a compilation error.
C. some: This option is incorrect because the code won't reach this block due to the compilation error mentioned above.
D. Compilation fails: This option is correct. The code will fail to compile due to the invalid syntax in the else block. The correct syntax for an if-else statement is:
if (condition) {
// code block for true case
} else {
// code block for false case
}
Therefore, the correct code should be:
public static void main(String[] args) {
String str = "null";
if (str == null) {
System.out.println("null");
} else if (str.length() == 0) {
System.out.println("zero");
} else {
System.out.println("some");
}
}
The Answer is: D