Autonomic self-healing of java resources
View Patent ↗A method and system for using a JAVA™ Custom ClassLoader to dynamically build and maintain a list of JAVA™ Class Files and resources that are used by applications that run in Point Of Sale (POS) terminals or other POS devices. The JAVA™ Class Files and resources are ordinarily obtained from a file server known as a controller. If communication between the POS terminal and the controller is lost, other POS devices dynamically collaborate in a “self healing” process to find and provide the required resources (e.g., JAVA™ Class Files) to run the POS terminal in an off-line mode. The present system is thus autonomic, self-learning and self-healing.
1. A method comprising:
creating a Custom Class Loader from a Base Class Loader in a JAVA™ environment, wherein the Custom Class Loader is able to load JAVA™ class files either using a JAVA™ “import” mechanism or a JAVA™ Class.forName( ) mechanism, wherein the JAVA™ environment operates within an IBM™ 4690 Operating System environment, and wherein the Custom Class Loader operates in a first Point Of Sale (POS) device that is coupled to a controller;
using the Custom Class Loader to dynamically load JAVA™ Classes from the controller to the first POS device, wherein the first POS device requests the JAVA™ Classes in response to a request from an application running on the first POS device, wherein the first POS device is coupled to other POS devices, the other POS devices including a second POS device and a third POS device;
upon an interruption in communication between the controller and the first POS device, sending a request from the first POS device to the other POS devices requesting the JAVA™ Class;
storing in the second POS device a record of JAVA™ Classes stored in the third POS device;
sending a request for the JAVA™ Class from the first POS device to the second POS device, wherein the requested JAVA™ Class is not stored in the second POS device, and wherein the requested JAVA™ Class is stored in the third POS device; and
in response to the second POS device not having the requested JAVA™ Class, sending the first POS device information identifying the third POS device as having the requested JAVA™ Class.
2. The method of claim 1 , wherein the information includes a TCP/IP address for the third POS device.
3. The method of claim 1 , wherein the first POS device is a POS terminal.
4. A method performed in an Object Oriented Programming (OOP) language environment that supports class files, the method comprising:
creating a Custom Class Loader from a Base Class Loader, wherein the Custom Class Loader is able to load class files, and wherein the Custom Class Loader operates in a first Point Of Sale (POS) device that is coupled to a controller;
using the Custom Class Loader to dynamically load Classes from the controller to the first POS device, wherein the first POS device requests the Classes in response to a request from an application running on the first POS device, wherein the first POS device is coupled to other POS devices, the other POS devices including a second POS device and a third POS device;
upon an interruption in communication between the controller and the first POS device, sending a request from the first POS device to the other POS devices requesting the Class;
storing in the second POS device a record of Classes stored in the third POS device;
sending a request for the Class from the first POS device to the second POS device, wherein the requested Class is not stored in the second POS device, and wherein the requested Class is stored in the third POS device; and
in response to the second POS device not having the requested Class, sending the first POS device information identifying the third POS device as having the requested Class.
5. The method of claim 4 , wherein the information includes a TCP/IP address for the third POS device.
6. The method of claim 4 , wherein the first POS device is a POS terminal.
7. A computer storage medium comprising:
computer executable code for creating a Custom Class Loader from a Base Class Loader, wherein the Custom Class Loader is able to load class files, and wherein the Custom Class Loader operates in a first Point Of Sale (POS) device that is coupled to a controller;
computer executable code for using the Custom Class Loader to dynamically load Classes from the controller to the first POS device, wherein the first POS device requests the Classes in response to a request from an application running on the first POS device, wherein the first POS device is coupled to other POS devices, the other POS devices including a second POS device and a third POS device;
computer executable code for upon an interruption in communication between the controller and the first POS device, sending a request from the first POS device to the other POS devices requesting the Class;
computer executable code for storing in the second POS device a record of Classes stored in the third POS device;
computer executable code for sending a request for the Class from the first POS device to the second POS device, wherein the requested Class is not stored in the second POS device, and wherein the requested Class is stored in the third POS device; and
computer executable code for in response to the second POS device not having the requested Class, sending the first POS device information identifying the third POS device as having the requested Class.
8. The computer storage medium of claim 7 , wherein the information includes a TCP/IP address for the third POS device.
9. The computer storage medium of claim 7 , wherein the first POS device is a POS terminal.