Immutable array in Java

java arrays immutability
ignoramus picture ignoramus · Sep 13, 2010 · Viewed 104.8k times · Source

Is there an immutable alternative to the primitive arrays in Java? Making a primitive array final doesn't actually prevent one from doing something like

final int[] array = new int[] {0, 1, 2, 3};
array[0] = 42;

I want the elements of the array to be unchangeable.

Answer

Jason S picture Jason S · Sep 13, 2010

Not with primitive arrays. You'll need to use a List or some other data structure:

List<Integer> items = Collections.unmodifiableList(Arrays.asList(0,1,2,3));

Related questions

How do I declare and initialize an array in Java?

How do I declare and initialize an array in Java?

Read More
What's the simplest way to print a Java array?

In Java, arrays don't override toString(), so if you try to print one directly, you get the className + '@' + the hex of the hashCode of the array, as defined by Object.toString(): int[] intArray = new int[] {1, 2, 3, 4, 5}; System.out.println(…

Read More
How do I determine whether an array contains a particular value in Java?

I have a String[] with values like so: public static final String[] VALUES = new String[] {"AB","BC","CD","AE"}; Given String s, is there a good way of testing whether VALUES contains s?

Read More