Problem: Product Name: VisiBroker Product Version: 5.x onwards Product Component: All Platform/OS version: All JDK: Java 1.4 onwards Certain CORBA functionality like creation of POA in Java requires classes packaged in vbjendorse.jar . Unlike other jar files, placing vbjendorse.jar in the Java classpath does not work. In Java 1.4 and 1.5, Sun included in its distributions, a functional ORB based on CORBA 2.3.1 specification. Sun ORB includes org.omg.* packages which VisiBroker also uses. However, VisiBroker made enhancement to certain org.omg classes to support CORBA 2.6 specification. This inevitably leads to the question of which classes (sharing the same name) should the JVM load and use? Resolution: To solve this problem, Sun introduced the "endorsed" mechanism to allow third-party classes (with a higher specification version) to take precedence over Sun's classes. Only versions of the classes that are newer than that provided by the JRE may be overridden. Such classes provided by third-party vendors should be packaged in a jar and placed in a directory that the Java system property java.endorsed.dirs is mapped to. In VisiBroker context, these classes are contained within the vbjendorse.jar file. After a successful installation of VisiBroker, this vbjendorse.jar file is to be found in VBROKERDIR /lib/endorsed folder. Customer using their own mechanism to start the JVM running VisiBroker ORB has to set the Java system property " java.endorsed.dirs " to include the directory where vbjendorse.jar resides ( java -Djava.endorsed.dirs= VBROKERDIR /lib/endorsed ....). Starting CORBA server or client applications using "vbj" launcher does not require setting of this system property as "vbj" is already programmed to do so prior to starting up the JVM. In applet context, user has to create a directory named "endorsed" in the lib folder of the JRE that is used by the browser and place a copy of vbjendorse.jar in the "endorsed" directory. (Example, if a browser in Windows platform is accessing the Java Runtime in C:\Program Files\Java\jre1.5.0_09, then the default endorsed directory that the browser's Java looks for is C:\Program Files\Java\jre1.5.0_09\lib\endorsed.) Note that placing the jar in the applet archive tag (to download the jar when the applet is run) does not work. Resources: Endorsed Standards Override Mechanism: http://docs.oracle.com/javase/1.5.0/docs/guide/standards/ CORBA support in J2SE1.4: http://docs.oracle.com/javase/1.5.0/docs/api/org/omg/CORBA/doc-files/compliance.html CORBA support in J2SE 5.0: http://docs.oracle.com/javase/1.5.0/docs/guide/idl/compliance.html
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