@ParametersAreNonnullByDefault @Nonnull

Package net.java.truelicense.core

Provides life cycle management for license keys.

See: Description

Interface Summary

Interface	Description
LicenseApplicationContext	A context which has been derived from a license management context.
LicenseApplicationContext.KsbaInjection<Target>	Injects a Key Store Based Authentication (KSBA) into some target.
LicenseApplicationContext.PbeInjection<Target>	Injects a Password Based Encryption (PBE) into some target.
LicenseAuthorization	Defines an authorization for the license key life cycle management operations.
LicenseAuthorizationProvider	Provides a license authorization.
LicenseConsumerContext	A derived context for license consumer applications.
LicenseConsumerContext.ManagerBuilder	A builder for license consumer managers.
LicenseConsumerManager	Defines the life cycle management operations for license keys in consumer applications.
LicenseInitialization	Defines a license initialization.
LicenseInitializationProvider	Provides a license initialization.
LicenseManagementContext	A root context for the life cycle management of license keys.
LicenseParameters	Defines license parameters.
LicenseParametersProvider	Provides license parameters.
LicenseProvider	Provides a license.
LicenseSubjectProvider	Provides a licensing subject.
LicenseValidation	Defines a license validation.
LicenseValidationProvider	Provides a license validation.
LicenseVendorContext	A derived context for license vendor applications alias license key tools.
LicenseVendorContext.ManagerBuilder	A builder for license vendor managers.
LicenseVendorManager	Defines the life cycle management operations for license keys in vendor applications alias key tools.

Class Summary

Class	Description
BasicLicenseManagementContext	A basic license management context.
BasicV2LicenseManagementContext	The root context for the management of V2 format license keys.
License	A Java Bean which defines and provides the common properties of any license.
V1LicenseManagementContext	The root context for the management of Version 1 (V1) format license keys.
V2XmlLicenseManagementContext	The root context for the management of Version-2-with-XML (V2/XML) format license keys.

Exception Summary

Exception	Description
LicenseManagementException	Indicates an issue when creating, installing, viewing, verifying or uninstalling a license key.
LicenseValidationException	Indicates that a license validation failed.

Package net.java.truelicense.core Description

Provides life cycle management for license keys. License keys are small binary objects which can be stored in a file, a preferences node, the heap or any custom implementation of the Store interface. License keys pass the following life cycle phases:

1. Creation,
2. installation,
3. viewing,
4. verification and
5. uninstallation

These operations are defined in the LicenseVendorManager and the LicenseConsumerManager interfaces. A Free Trial Period (FTP) is configurable with a license consumer manager in order to ease the conversion of prospects to customers. License consumer managers can also get chained in order to unlock application features based on the purchased license keys.

A license bean is an instance of the License class. This class follows the Java Bean pattern and defines common properties for the licensing subject, issue date, issuer, holder, consumer type/amount, validity period and custom data. These properties get initialized and validated whenever a license key gets created. They also get validated whenever a license key gets installed or verified.

A license key gets created from a license bean by applying the following function composition:

  encrypt(compress(encode(sign(encode(validate(initialize(duplicate(licenseBean))))))))
 

When installing or verifying a license key, a duplicate of the original license bean gets derived by applying the following (almost inverse) function composition (note that there is no initialization and hence no duplication required):

  validate(decode(authenticate(decode(decompress(decrypt(licenseKey))))))
 

The validation step is skipped when a license key is just viewed. Encryption is done via JCA with a configurable password based encryption algorithm. Authentication is done via JCA with a configurable key store type and signature algorithm. Encoding is done with XMLEncoder for simple, schema-less, yet resilient long term archival.

TrueLicense 2 retains full compatibility with TrueLicense 1 (V1) format license keys plus defines a new V2 format for enhanced encryption and compression. Applications select the class V1LicenseManagementContext or V2XmlLicenseManagementContext as their starting point for configuring a license vendor or consumer manager. These classes can get subclassed to customize special aspects, such as performing additional license validation steps, providing an authoritative clock et al. However, TrueLicense 2 has been designed so that typical applications don't need to subclass or implement any class or interface of its API.

For security, passwords are represented as an instance of the ObfuscatedString class. Other security critical string (algorithms, paths, etc.) are annotatable with @Obfuscate and processible with the TrueLicense Maven Plugin for simple, reliable obfuscation of constant string values in the byte code for license applications.

Warning: To protect against reverse engineering and modification of your application, it is strictly necessary to generally process all byte code which is comprised in your deployment unit with a tool for byte code obfuscation. TrueLicense does not provide general byte code obfuscation because there exist good quality third party tools, e.g. ProGuard.

Author:

Christian Schlichtherle