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The following code tests whether a float value is denormalized in strictfp FP-strict mode or for platforms that lack extended range support. Testing for denormalized numbers in the presence of extended range support is platform-dependent; see rule NUM06-J for additional information.

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Here is a small program, along with its output, that demonstrates the print representation of denormalized numbers.

strictfp class FloatingPointFormats {
  public static void main(String[] args) {
    float x = 0x1p-125f;
    double y = 0x1p-1020;
    System.out.format("normalized float with %%e    : %e\n", x);
    System.out.format("normalized float with %%a    : %a\n", x);
    x = 0x1p-140f;
    System.out.format("denormalized float with %%e  : %e\n", x);
    System.out.format("denormalized float with %%a  : %a\n", x);
    System.out.format("normalized double with %%e   : %e\n", y);
    System.out.format("normalized double with %%a   : %a\n", y);
    y = 0x1p-1050;
    System.out.format("denormalized double with %%e : %e\n", y);
    System.out.format("denormalized double with %%a : %a\n", y);
  }
}

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Because this operation is imprecise, this code produces the following output when run in FP-strict mode:

Original      : 0.33333334
Denormalized  : 2.8E-45
Restored      : 0.4

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This code produces the following output in FP-strict mode:

Original      : 0.3333333333333333
Denormalized  : 2.333333333333333E-45
Restored      : 0.3333333333333333

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CVE-2010-4476 [CVE 2008 ] reports a vulnerability in the Double.parseDouble() method in Java 1.6 update 23 and earlier, Java 1.5 update 27 and earlier, and 1.4.2_29 and earlier. This vulnerability causes a DoS denial of service when this method is passed a crafted string argument. The value 2.2250738585072012e-308 is close to the minimum normalized, positiv,e double-precision floating-point number, and when encoded as a string, it triggers an infinite loop of estimations during conversion to a normalized or denormalized double.

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