Java, Simplified check if int array contains int

user_1565994 0
Viewed 301829

Basically my mate has been saying that I could make my code shorter by using a different way of checking if an int array contains an int, although he won't tell me what it is :P.

Current: 

public boolean contains(final int[] array, final int key) {
    for (final int i : array) {
        if (i == key) {
            return true;
        }
    }
    return false;
}

Have also tried this, although it always returns false for some reason.

public boolean contains(final int[] array, final int key) {
    return Arrays.asList(array).contains(key);
}

Could anyone help me out?

Thank you.

int contains arrays java
15 Answers

You can convert your primitive int array into an arraylist of Integers using below Java 8 code,

List<Integer> arrayElementsList = Arrays.stream(yourArray).boxed().collect(Collectors.toList());

And then use contains() method to check if the list contains a particular element,

boolean containsElement = arrayElementsList.contains(key);
user_82214700

Try this:

public static void arrayContains(){
    int myArray[]={2,2,5,4,8};

    int length=myArray.length;

    int toFind = 5;
    boolean found = false;

    for(int i = 0; i < length; i++) {
        if(myArray[i]==toFind) {
            found=true;
        }
    }

    System.out.println(myArray.length);
    System.out.println(found); 
}
user_61296130 
private static void solutions() {
    int[] A = { 1, 5, 10, 20, 40, 80 };
    int[] B = { 6, 7, 20, 80, 100 };
    int[] C = { 3, 4, 15, 20, 30, 70, 80, 120 };

    List<Integer> aList = Arrays.stream(A).boxed().collect(Collectors.toList());

    List<Integer> cList = Arrays.stream(C).boxed().collect(Collectors.toList());
    String s = "";
    for (Integer a : C) {
        if (aList.contains(a) && cList.contains(a)) {
            s = s.concat(String.valueOf(a)).concat("->");
        }
    }
}
user_115904040

Java 9+

public boolean contains(final int[] array, final int key) {
    return List.of(array).contains(key);
}
user_2602290
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