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This noncompliant code example uses a floating-point variable as a loop counter. The decimal number 0.1 cannot be precisely represented as a float or even as a double.

for (float x = 0.1f; x <= 1.0f; x += 0.1f) {
  System.out.println(x);
}

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This compliant solution uses an integer loop counter from which the desired floating-point value is derived.

for (int count = 1; count <= 10; count += 1) {
  float x = count/10.0f;
  System.out.println(x);
}

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This noncompliant code example uses a floating-point loop counter that is incremented by an amount that is typically too small to change its value given the precision.

for (float x = 100000001.0f; x <= 100000010.0f; x += 1.0f) {
  /* ... */
}

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This compliant solution uses an integer loop counter from which the floating-point value is derived. Additionally, it uses a double to ensure that the available precision suffices to represent the desired values. The solution also runs in FP-strict mode to guarantee portability of its results. See NUM06-J. Use the strictfp modifier for floating-point calculation consistency across platforms for more information.

for (int count = 1; count <= 10; count += 1) {
  double x = 100000000.0 + count;
  /* ... */
}

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[Bloch 2005]	Puzzle 34. Down for the count
[JLS 2005]	§4.2.3, Floating-Point Types, Formats, and Values
[Seacord 2015]	Image Added NUM09-J. Do not use floating-point variables as loop counters LiveLesson