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  4. 'Map' can be replaced with 'EnumMap'

'Map' can be replaced with 'EnumMap'

Last modified: 03 December 2024

Reports instantiations of java.util.Map objects whose key types are enumerated classes. Such java.util.Map objects can be replaced with java.util.EnumMap objects.

java.util.EnumMap implementations can be much more efficient because the underlying data structure is a simple array.

Example:

Map<MyEnum, String> myEnums = new HashMap<>();

After the quick-fix is applied:

Map<MyEnum, String> myEnums = new EnumMap<>(MyEnum.class);

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.

MapReplaceableByEnumMap
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 | Performance

Inspection Details

By default bundled with:

IntelliJ IDEA 2024.3, Qodana for JVM 2024.3,

Can be installed with plugin:

Java, 243.23126