Collections.singleton

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String init[] = { "One", "Two", "Three", "One", "Two", "Three" };

List list1 = new ArrayList(Arrays.asList(init));

List list2 = new ArrayList(Arrays.asList(init));

list1.remove("One");

System.out.println(list1);

// [Two, Three, One, Two, Three]

list2.removeAll(Collections.singleton("One"));

System.out.println(list2);

// [Two, Three, Two, Three]