How do I remove duplicate elements from a String Array in Java?

Using Java Collection framework API, the duplicate elements in a string array can be removed easily by converting the string array to List, creating a HashSet from the List that removes the duplicates and converting set to String array back. See the example below.

String[] data = { "a", "c", "b", "d","a", "c", "b", "d"};
System.out.println("Actual array: " + Arrays.toString(data));

List<String> strList = Arrays.asList(data);
Set<String> strSet = new HashSet<String>(strList);
String[] result = new String[strSet.size()];

strSet.toArray(result);

System.out.println("Array without duplicates: ");
for (String s : result) {
  System.out.print(s + ", ");
}

The above program can be shortened further as shown below.

String[] data = { "a", "c", "b", "d", "a", "c", "b", "d" };

data = new HashSet<String>(Arrays.asList(data)).toArray(new String[0]);

for (String s : data) {
	System.out.print(s + ", ");
}

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