Analyze the following program fragment: int x; double d = 1.5; switch (d) { case 1.0: x = 1; case 1.5: x = 2; case 2.0: x = 3; }
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The program has a syntax error because the required break statement is missing in the switch statement.
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The program has a syntax error because the required default case is missing in the switch statement
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The switch control variable cannot be double.
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No errors
Java switch statements only work with integral types (byte, short, char, int) and their wrapper classes, enums, and String. A double variable like 'd' cannot be used as a switch expression because doubles are not integral and floating-point equality comparisons are unreliable. The break statement and default case are optional: their absence does not cause a syntax error.
To analyze the given program fragment, let's go through each option:
Option A) The program has a syntax error because the required break statement is missing in the switch statement. This option is incorrect because the absence of a break statement is not a syntax error. However, it can lead to unexpected behavior in the program, such as falling through to the next case.
Option B) The program has a syntax error because the required default case is missing in the switch statement. This option is incorrect because the absence of a default case is not a syntax error. A default case is optional and is executed when none of the cases match the switch control variable.
Option C) The switch control variable cannot be double. This option is correct. In C, the switch control variable can only be an integer type (char, int, long, enum). It cannot be a floating-point type like double. Therefore, this program fragment would result in a compilation error.
Option D) No errors. This option is incorrect because, as mentioned earlier, the program fragment would result in a compilation error due to using a double as the switch control variable.
Therefore, the correct answer is C) The switch control variable cannot be double.