'if' statement with negated condition

Reports if statements that contain else branches and whose conditions are negated.

Flipping the order of the if and else branches usually increases the clarity of such statements.

There is a fix that inverts the current if statement.

Example:

    void m(Object o1, Object o2) {
        if (o1 != o2) {
            System.out.println(1);
        }
        else {
            System.out.println(2);
        }
    }

After applying the quick-fix:

    void m(Object o1, Object o2) {
        if (o1 == o2) {
            System.out.println(2);
        } else {
            System.out.println(1);
        }
    }

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.

IfStatementWithNegatedCondition

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 | Control flow issues

Use the Ignore '!= null' comparisons option to ignore comparisons of the != null form.

Use the Ignore '!= 0' comparisons option to ignore comparisons of the != 0 form.

Inspection options

Here you can find the description of settings available for the 'if' statement with negated condition inspection, and the reference of their default values.

Ignore '!= null' comparisons: Default: Selected
Ignore '!= 0' comparisons: Not selected

Inspection Details
By default bundled with:	IntelliJ IDEA 2024.2, Qodana for JVM 2024.2,
Can be installed with plugin:	Java, 242.22892

Last modified: 11 September 2024