Object management system and method for distributed object system

• US 6,701,323 B2
• Filed: 01/29/2001
• Issued: 03/02/2004
• Est. Priority Date: 04/18/2000
• Status: Expired due to Fees

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Iwasaki, Motoaki, Chaki, Yuuichiro, Sashino, Atsushi
• Primary Examiner(s): ALAM, SHAHID AL
• Application Number:
  US09/772,294
• Publication Number:
  US 20010032239A1
• Time in Patent Office: 1,128 Days
• Field of Search: 707/10, 707/103.R, 707/102, 709/105, 709/203, 709/219, 709/223, 709/224, 709/226, 709/229
• US Class Current: 1/1
• CPC Class Codes: G06F 9/465 Distributed object oriented systems remote method invocation [RMI] G06F9/548
• CPC Class Codes: G06F 9/505 considering the load
• CPC Class Codes: Y10S 707/99944 Object-oriented database structure

Abstract

A distributed object system having a load balancing feature that can be expanded by adding a new computer to the cluster of server computers. Objects can be activated and deactivated and system service alteration is performed by renewing objects. By request from a client, the object invocation unit obtains object code and object data from the object access unit in response to remote object invocation, executes the requested method, and requests the object access unit to overwrite the object data. The object manager unit activates or deactivates an object.

Claims

1. An object management method applicable to distributed object system, which includes at least one client computer at least one server computer, and at least one managing computer, the method comprising:

providing the at least one server computer with a load balancing feature.

obtaining object code and object data from the at least one managing computer in response to a remote object invocation from the at least one client computer,

wherein said object code includes an attribute which indicates whether a read or a write is to be conducted during execution of a method defined by said object code,

executing a requested method of the object on the at least one server computer; and

performing object data overwrite on the at least one managing computer, when the attribute indicates that a write is to be conducted during execution of said method defined by said object code.

2. The method of claim 1, comprising:

at least one of activating objects and deactivating objects only on the at least one managing computer.

3. The method of claim 1, comprising:

performing senalized object invocation and method execution on the at least one server computer when a plurality of remote object invocations of a same object to execute a synchronized method of the object are issued from the at least one client-run computer.

4. The method of claim 1, comprising:

performing concurrent object invocation and method execution on the at least one server computer when a plurality of remote object invocations of a same object to execute a non-synchronized method of the object are issued from the at least one client-run computer.

5. The method of claim 1, comprising:

requesting the at least one managing computer to overwrite the object data and change the object data use flag when a write method is executed on the at least one server-run computer.

6. The method of claim 1, comprising:

performing both object data overwrite and object data use flag change on the at least one server computer when a read-only and non-synchronized method is executed on the at least one server-run computer.

7. The method of claim 1, comprising:

requesting the at least one managing computer to simply update the object data use flag when a read-only and synchronized method is executed on the at least one server computer.

8. The method of claim 1, comprising:

providing an object database containing catalog object and data and cart object and data.

9. A server computer, comprising:

an object invocation unit; and

a load balancing unit for selecting the server computer to perform a method execution task according to a load condition and for sending a request message to the object invocation unit of the selected server computer,

wherein the object invocation unit receives the request message from the load balancing unit, sends a request for object code and object data to a managing computer, receives object code and object data from the managing computer, said object code includes an attribute which indicates whether a read or a write is to be conducted during execution of a method defined by said object code, executes the requested method, and sends object data fixed after said method has been executed and a request for object data overwrite to the managing computer, when the attribute indicates that a write is to be conducted during execution of said method defined by said object code.

10. A managing computer, comprising:

an object access unit for receiving a request to obtain object code and object data from a server computer, obtaining object code from an object code table and obtaining object data from an object data table, said object code includes an attribute which indicates whether a read or a write is to be conducted dung execution of a method defined by said object code, sending the obtained object code and the obtained object data to the server computer, receiving object data fixed after said method has been executed and a request for object data overwrite, and writing object data fixed after said method has been executed over corresponding object data in the object data table, when the attribute indicates that a write is to be conducted during execution of said method defined by said object code; and

an object manager unit for receiving a command to activate an object from an object management user program, retrieving the object from a database of executable-formed objects, registering object code into an object code table wherein object codes are stored, and registering object data into an object data into an object data table wherein object data are stored,

wherein the object management user program provides at least one object activation command and at least one object deactivation command to the object manager unit, and

wherein the database of executable-formed objects comprising the objects are represented as executable programs.

11. A program for implementing an object management method in a distributed object system, the distributed object system including at least one client computer, at least one server computer, and at least one managing computer, the program when executed causes the distributed object system to perform the steps of:

providing the at least one server computer with a load balancing feature;

obtaining object code and object data from the at least one managing computer in response to a remote object invocation from the at least one client-run computer,

wherein said object code includes an attribute which indicates whether a read or a write is to be conducted during execution of a method defined by said object code,

executing a requested method of the object on the at least one server-run computer, and

performing object data overwrite on the at least one managing computer, when the attribute indicates that a write is to be conducted during execution of said method defined by said object code.