Unpredictable 'BigDecimal' constructor call

Reports calls to BigDecimal constructors that accept a double value. These constructors produce BigDecimal that is exactly equal to the supplied double value. However, because doubles are encoded in the IEEE 754 64-bit double-precision binary floating-point format, the exact value can be unexpected.

For example, new BigDecimal(0.1) yields a BigDecimal object. Its value is 0.1000000000000000055511151231257827021181583404541015625 which is the nearest number to 0.1 representable as a double. To get BigDecimal that stores the same value as written in the source code, use either new BigDecimal("0.1") or BigDecimal.valueOf(0.1).

Example:

class Constructor {
  void foo() {
    new BigDecimal(0.1);
  }
}

After the quick-fix is applied:

class Constructor {
  void foo() {
    new BigDecimal("0.1");
  }
}

Inspection options

Option	Type	Default
Ignore constructor calls with variable or method call arguments	Checkbox	true
Ignore constructor calls with multiple literals (e.g. 0.1 + 0.2)	Checkbox	false

Inspection Details
Available in:	IntelliJ IDEA 2023.3, Qodana for JVM 2023.3
Plugin:	Java, 233.SNAPSHOT

Last modified: 13 July 2023