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MAKING a list unmodifiable - Lists - Java
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Java - Lists - Making a list unmodifiable
Making a list unmodifiable

The Collections class provides a way to make a list unmodifiable:

List<String> ls = new ArrayList<String>();
List<String> unmodifiableList = Collections.unmodifiableList(ls);

If you want an unmodifiable list with one item you can use:

List<String> unmodifiableList = Collections.singletonList("Only string in the list");

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