Java SDK

The Java 17+ SDK is com.dycrypt:dycrypt-license-sdk. It has no runtime dependencies and uses Java’s standard cryptography and HTTP APIs.

Install

Until the package is published to a public registry, build it from the DYCRYPT SDK checkout:

cd sdk/java
mvn install

<dependency>
  <groupId>com.dycrypt</groupId>
  <artifactId>dycrypt-license-sdk</artifactId>
  <version>0.1.0</version>
</dependency>

LicenseVerifier verifier = LicenseVerifier.builder()
    .publicKeyPem(Files.readString(Path.of("product-public-key.pem")))
    .productKey("your-product-key")
    .build();

LicenseResult result = verifier.verify(
    Files.readString(Path.of("customer.lic"))
);

if (!result.valid()) {
    throw new IllegalStateException("Unlicensed: " + result.reason());
}

Build the verifier once and reuse it. It is immutable and holds only public verification material.

Print a machine fingerprint

Full Offline and offline-activated Hybrid licences need the customer’s fingerprint before issue:

import com.dycrypt.license.Fingerprint;

if (args.length > 0 && "--fingerprint".equals(args[0])) {
    System.out.println(Fingerprint.of());
    return;
}

Run this on the machine that will use the licence and copy the complete DYC1.… output into the DYCRYPT issue form.

Configure one verifier

Copy the public key, product key, issuer URL, and organisation slug from the product’s Quick Start Guide.

import com.dycrypt.license.*;
import java.nio.file.*;
import java.time.Duration;

LicenseVerifier verifier = LicenseVerifier.builder()
    .publicKeyPem(Files.readString(Path.of("product-public-key.pem")))
    .productKey("your-product-key")
    .issuer("https://app.dycrypt.com", "your-org-slug")
    .policy(OnlinePolicy.ADVISORY)
    .timeout(Duration.ofSeconds(5))
    .build();

Omit issuer(...) for a Full Offline product. A malformed public key or missing product key fails during construction instead of turning every licence into an unexplained invalid result.

Full Offline

LicenseResult result = verifier.verify(
    Files.readString(Path.of("customer.lic"))
);
enforce(result);

verify() never performs a network request and never throws for hostile licence input. A wrong machine, signature, product, or schema returns INVALID.

Full Online and Hybrid

LicenseResult result = verifier.check(
    Files.readString(Path.of("customer.lic"))
);
enforce(result);

check() verifies locally first and sends only a locally verified licence to DYCRYPT. Call it at startup and on the check interval configured for your product. The SDK does not start a background scheduler.

Keep the verifier for the lifetime of the process. If your application persists the time of a successful check across restarts, restore it with recordGoodCheck(licenceId, instant) before relying on the remaining offline window.

Handle every status

static void enforce(LicenseResult result) {
    switch (result.status()) {
        case ACTIVE -> { /* enable licensed functionality */ }
        case GRACE -> warn("Licence expired; grace period is active");
        case PENDING -> stop("Licence starts at " + result.startsAt());
        case STALE -> stop("Reconnect to refresh the licence status");
        case REVOKED -> stop("This licence was revoked");
        case EXPIRED -> stop("This licence expired");
        case INVALID, UNKNOWN -> stop("Licence rejected: " + result.reason());
    }
}

ACTIVE and GRACE are the only valid statuses.

Read product claims

int maxUsers = result.getInt("maxUsers", 5);
String edition = result.getString("edition", "standard");
boolean exportEnabled = result.getBoolean("exportEnabled", false);
List<String> features = result.getStringList("features", List.of());

Typed accessors return your fallback for an absent or wrong-type claim and never coerce values silently.