# QESDK Java API Source: [https://docs.qualcomm.com/doc/80-PK177-134/topic/java_api.html](https://docs.qualcomm.com/doc/80-PK177-134/topic/java_api.html) The QESDK class provides the main methods that are used to register an Android application package (APK) and validate the corresponding license file. - **[QESDK specific APIs](https://docs.qualcomm.com/doc/80-PK177-134/topic/qesdk_specific_apis.html)** - **[Initialize or de-initialize individual subsystems](https://docs.qualcomm.com/doc/80-PK177-134/topic/init_or_deinit_individual_subsystems.html)** Applications can initialize and de-initialize services independently. - **[QESDK Java callback interfaces](https://docs.qualcomm.com/doc/80-PK177-134/topic/qesdk_java_callback_interfaces.html)** - **[QESDK exceptions](https://docs.qualcomm.com/doc/80-PK177-134/topic/java_exceptions.html)** QESDK service and subsystem service exceptions are defined in the QESDK exception. - **[Example code](https://docs.qualcomm.com/doc/80-PK177-134/topic/java_example_code.html)** The following sample code shows the usage of QESDK Java APIs: **Parent Topic:** [Qualcomm Enhanced Software Development Kit](https://docs.qualcomm.com/doc/80-PK177-134/topic/qesdk_overview.html) Last Published: Nov 14, 2024 [Previous Topic Qualcomm Enhanced Software Development Kit](https://docs.qualcomm.com/bundle/publicresource/80-PK177-134/topics/qesdk_overview.md) [Next Topic QESDK specific APIs](https://docs.qualcomm.com/bundle/publicresource/80-PK177-134/topics/qesdk_specific_apis.md)