root@generate-random:~/api-keys/java$ _

Generate API Keys in Java

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[ Code Example - Quick Summary ]

Language: Java

What: Generate cryptographically secure API keys in Java using <code>SecureRandom</code> for enterprise applications. Suitable for Spring Boot, microservices, and RESTful APIs.

Try it: Use our interactive Api-keys generator or integrate this code into your Java application.

Generate cryptographically secure API keys in Java using SecureRandom for enterprise applications. Suitable for Spring Boot, microservices, and RESTful APIs. Looking for other languages? Check our code examples in PHP , JavaScript , Python , C# , C++ , Ruby and Go or use our interactive web generator.

Java Code Example

import java.security.SecureRandom;
import java.util.Base64;

public class ApiKeyGenerator {
    private static final SecureRandom random = new SecureRandom();

    public static String generateApiKey(int length) {
        byte[] bytes = new byte[length];
        random.nextBytes(bytes);

        // Convert to hexadecimal
        StringBuilder sb = new StringBuilder();
        for (byte b : bytes) {
            sb.append(String.format("%02x", b));
        }
        return sb.toString();
    }

    public static String generateApiKeyBase64(int length) {
        byte[] bytes = new byte[length];
        random.nextBytes(bytes);

        // Base64 URL-safe encoding
        return Base64.getUrlEncoder()
                     .withoutPadding()
                     .encodeToString(bytes);
    }

    public static void main(String[] args) {
        // Generate 256-bit (32 byte) API key
        String apiKey = generateApiKey(32);
        System.out.println("Hex: " + apiKey);
        // Output: "a7f3e9c2d8b4f1a6e5c9d7b3f8a2e6c4d9b5f7a3e8c6d2b9f4a7e1c5d8b3f6a9"

        String apiKeyBase64 = generateApiKeyBase64(32);
        System.out.println("Base64: " + apiKeyBase64);
        // Output: "p3_pwr2L8RpuXJbT-IouaztX86jG0rmU9KfhxdizNpo"
    }
}

[EXPLANATION]

Java's SecureRandom class provides cryptographically strong random number generation. The implementation uses Base64.getUrlEncoder().withoutPadding() for URL-safe encoding without padding characters. This approach is thread-safe and suitable for high-concurrency enterprise applications.

Expected Output

Hexadecimal: a7f3e9c2d8b4f1a6e5c9d7b3f8a2e6c4d9b5f7a3e8c6d2b9f4a7e1c5d8b3f6a9
Base64 URL-safe: p3_pwr2L8RpuXJbT-IouaztX86jG0rmU9KfhxdizNpo
With prefix: sk-live-p3_pwr2L8RpuXJbT-IouaztX86jG0rmU9KfhxdizNpo