Sunday, 22 January 2017

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?


Answer



Arrays.asList(yourArray).contains(yourValue)



Warning: this doesn't work for arrays of primitives (see the comments).






Since you can now use Streams.



String[] values = {"AB","BC","CD","AE"};
boolean contains = Arrays.stream(values).anyMatch("s"::equals);



To check whether an array of int, double or long contains a value use IntStream, DoubleStream or LongStream respectively.



Example



int[] a = {1,2,3,4};
boolean contains = IntStream.of(a).anyMatch(x -> x == 4);

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