Classes not loaded by the custom class loader must be loaded by the system class loader, based on the search order specified by the server class path settings described here.
Like other Java programs, the system class loader running in EAServer loads classes in the order specified by the CLASSPATH environment variable. However, you can configure additional entries in the Class Path property, on the General page of the server’s property pages in the Web console (or the classPath property if configuring with the Ant setProperties task). For details, see “General tab”.
In some cases, you may need to override class versions that are part of the Java runtime core classes. For example, you may need to use a newer version of the XML parsing API (org.xml.*) packages. You cannot override these classes by setting the CLASSPATH environment variable or Class Path server property. Instead, you must use the Java Endorsed Standards Override Mechanism.
The Java Endorsed Standards Override Mechanism allows you to place JAR files in a directory specified by the java.endorsed.dirs Java system property. Classes in the JAR files override like-named classes in the Java core runtime classes. For more information, see Java Endorsed Standards Override Mechanism.
To use this mechanism with EAServer, place JAR files containing the classes that override core runtime class versions in the lib/endorsed subdirectory of your EAServer installation.
You can place non-refreshable extension JARS in the lib/ext directory. These are added automatically to the class path during server start-up. You can place refreshable extension JARS in the lib/default/ext directory. These are loaded by the lib.default-ext class loader, which is a child of the default class loader.
The BOOTCLASSPATH environment variable allows you to override class versions that are part of the Java runtime core classes. Sybase recommends that you use the Java Endorsed Standards Override mechanism to override core runtime classes rather than setting this environment variable.
