# Java Find a Specific Value in an Array Using Streams

> Use the Stream API's anyMatch method to check if a Java array contains a value, or convert the array to a list with Arrays.asList for reference types

**URL:** https://sentry.io/answers/find-a-specific-value-in-an-array-in-java/

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## The Problem

Using Java, how can I test whether an array contains a specific value?

## The Solution

We can achieve this for an array of any type using Java's [Stream API](https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/util/stream/Stream.html), introduced in Java 8. Streams are a method for processing collections of objects and can be used to perform operations such as finding values in arrays without having to explicitly loop through them. In a single line of code, we can give a stream a function to execute at every element in a given collection and retrieve the result. For example, to find a string in an array of strings, we could use the following code:

```java
import java.util.Arrays;

public class Main {
    public static void main(String[] args) {

        String[] products = new String[]{"Coffee", "Tea", "Chocolate Bar"};
        if (Arrays.stream(products).anyMatch("Coffee"::equals)) {
            System.out.println("Array contains 'Coffee'!");
        } else {
            System.out.println("Array does not contain 'Coffee'.");
        }
    }
}
```

Different stream types are required for arrays of different types. To find an integer in an array of integers, we could use an [`IntStream`](https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/util/stream/IntStream.html). For example:

```java
import java.util.stream.IntStream;

public class Main {
    public static void main(String[] args) {

        int[] values = {1, 2, 3, 4, 5};
        if (IntStream.of(values).anyMatch(x -> x == 3)) {
            System.out.println("Array contains 3!");
        } else {
            System.out.println("Array does not contain 3.");
        }
    }
}
```

We can adapt this for longs or doubles by using a [`LongStream`](https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/util/stream/LongStream.html) or [`DoubleStream`](https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/util/stream/DoubleStream.html) instead.

An alternative but less generalizable method for achieving this is to cast our array to a list using [`Arrays.asList`](https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/util/Arrays.html#asList(T...)) and then use the [`contains`](https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/util/Collection.html#contains(java.lang.Object)) method on that list. While this may be more readable for a developer unfamiliar with Java's Stream API, it does not work for primitive values like for arrays with ints, doubles, or longs. However, it will work for an array of strings:

```java
import java.util.Arrays;

public class Main {
    public static void main(String[] args) {

        String[] products = new String[]{"Coffee", "Tea", "Chocolate Bar"};
        if (Arrays.asList(products).contains("Coffee")) {
            System.out.println("Array contains 'Coffee'!");
        } else {
            System.out.println("Array does not contain 'Coffee'.");
        }
    }
}
```

Note that if we attempt this same approach with an array of primitive types, the `contains` method will not throw an error, but will always return `false`, even if the array contains the value we specify. We can run the code below to verify this:

```java
// BROKEN CODE DO NOT USE

import java.util.Arrays;

public class Main {
    public static void main(String[] args) {

        int[] values = {1, 2, 3, 4, 5};
        if (Arrays.asList(values).contains(3)) {
            System.out.println("Array contains 3!");
        } else { // this block will be executed
            System.out.println("Array does not contain 3.");
        }
    }
}
// BROKEN CODE DO NOT USE
```

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*Source: [sentry.io/answers/find-a-specific-value-in-an-array-in-java/](https://sentry.io/answers/find-a-specific-value-in-an-array-in-java/)*