Pointless bitwise expression

Reports pointless bitwise expressions.

Such expressions include applying the & operator to the maximum value for the given type, applying the or operator to zero, and shifting by zero. Such expressions may be the result of automated refactorings not followed through to completion and are unlikely to be originally intended.

Examples:

  // Warning: operation is pointless and can be replaced with just `flags`
  // 0xFFFF_FFFF is the maximum value for an integer, and both literals are treated
  // as 32 bit integer literals.
  int bits = flags & 0xFFFF_FFFF;

  // Warning: operation is pointless and can be replaced with just `bits`
  // OR-ing with 0 always outputs the other operand.
  int or = bits | 0x0;

  // Warning: operation is pointless, as always results in 0
  int xor = or ^ or;

Locating this inspection

By ID

Can be used to locate inspection in e.g. Qodana configuration files, where you can quickly enable or disable it, or adjust its settings.

PointlessBitwiseExpression

Via Settings dialog

Path to the inspection settings via IntelliJ Platform IDE Settings dialog, when you need to adjust inspection settings directly from your IDE.

Settings or Preferences | Editor | Inspections | Java | Bitwise operation issues

Inspection options

Here you can find the description of settings available for the Pointless bitwise expression inspection, and the reference of their default values.

Ignore named constants in determining pointless expressions: Default: Selected

Availability

By default bundled with: IntelliJ IDEA 2024.1, Qodana for JVM 2024.1,
Can be installed with plugin: Java, 241.18072

Last modified: 18 June 2024