Manual array to collection copy

Reports code that uses a loop to copy the contents of an array into a collection.

A shorter and potentially faster (depending on the collection implementation) way to do this is using Collection.addAll(Arrays.asList()) or Collections.addAll().

Only loops without additional statements inside are reported.

Example:

  void addAll(List<String> list, String[] arr) {
    for (int i = 0; i < arr.length; i++) {
      String s = arr[i];
      list.add(s);
    }
  }

After the quick-fix is applied:

  void addAll(List<String> list, String[] arr) {
    Collections.addAll(list, arr);
  }

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.

ManualArrayToCollectionCopy

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 ID: ManualArrayToCollectionCopy

Suppressing Inspection

You can suppress this inspection by placing the following comment marker before the code fragment where you no longer want messages from this inspection to appear:

//noinspection ManualArrayToCollectionCopy

More detailed instructions as well as other ways and options that you have can be found in the product documentation:

IntelliJ IDEA 2025.3

Inspection Details
By default bundled with:	IntelliJ IDEA 2025.3, Qodana for JVM 2025.3,

Last modified: 03 December 2025