METHOD FOR PRESERVING THE STATE OF A JAVA APPLET DURING THE LIFETIME OF ITS CONTAINER

• US 20020152232A1
• Filed: 09/21/1998
• Published: 10/17/2002
• Est. Priority Date: 09/21/1998
• Status: Active Grant

• Current Assignee: Micro Focus Incorporated (Open Text Corporation)
• Original Assignee: Wall Data, Inc. (Open Text Corporation)
• Inventors: UPPIANO, KARL A., YOUNGER, JOSEPH C., WINE, VAUGHN H.
• Granted Patent: US 6,638,315 B2
• Time in Patent Office: Days
• US Class Current: 715/500
• CPC Class Codes: G06F 9/4493 Object persistence
• CPC Class Codes: Y10S 707/99953 Recoverability
• CPC Class Codes: Y10S 707/99957 Garbage collection

Abstract

The present invention is a method of controlling the existence of a Java object that is associated with a Web page in order to reuse the object rather than create a new one when the Web page is revisited. The invention provides a method for allowing an object to register with a persistence manager upon creation, which maintain objects registered with it while the Web page is no longer being viewed.

A Web browser receives one or more instructions that define a Web page. The browser translates the instructions to create a Web page, and invokes any Java objects that reside on the page. The objects then check with the persistence manager, which can be located on the page or within one or more of the objects. If the objects are present in the persistence manager, the objects in the persistence manager are used, rather than creating new objects. If the objects (or some subset thereof) do not exist within the persistence manager, the necessary objects are created and are registered with the persistence manager. The object remains registered with the persistence manager until such time as it no longer needs to persist (as determined by the users needs, not by the Web page being displayed within the Web browser) or until the Web browser or JVM is completely shut down. Registration with the persistence manager prevents the destruction of the object when the Web browser exits from a Web page.

Claims

1. A method of controlling the creation of a software object associated with a markup language document that at least partially defines a Web page displayed by a browser when the browser visits the Web page, the browser executing on a client computer connectable to a server computer, the method comprising:

receiving the markup language document that at least partially defines a Web page;

analyzing the markup language document to determine if an instruction to create the software object is contained therein;

determining whether the software object exists in a persistence manager object; and

if the software object does not exist in the persistence manager object, creating the software object and registering the software object with the persistence manager.

2. The method of claim 1, further comprising:

if the software object exists in the persistence manager object, returning the software object from the persistence manager.

3. The method of claim 1, wherein the steps of registering the software object with the persistence manager or returning the software object in the persistence manager is accomplished by persistence carriers contained in a static reference mechanism.

4. The method of claim 3, wherein the step of determining whether the software object exists in the persistence manager comprises:

passing a predetermined identifier of a desired persistence carrier to the persistence manager; and

using this predetermined identifier, determining whether the software object already exists.

5. The method of claim 2, wherein the steps of registering the software object with the persistence manager or returning the software object in the persistence manager is accomplished by persistence carriers contained in a static reference mechanism.

6. The method of claim 5, wherein the step of determining whether the software object exists in the persistence manager comprises:

passing a predetermined identifier of a desired persistence carrier to the persistence manager; and

using this predetermined identifier, determining whether the software object already exists.