ATG ear

We can create two types of ear in ATG :

• Development mode ear, the application draws its Nucleus configuration information from the ATG Web Commerce installation.
• Standalone mode ear, the application stores its configuration in the EAR file itself.

Differences

• Loading configuration and
• Handling output files such as log files and state information.
• dynamo.env

In WEB-INF/ATG-INF directory of the atg_bootstrap.war J2EE module contains file called dynamo.env, which defines Commerce application environment properties.

In a development-mode EAR, the dynamo.env file contains :

atg.dynamo.use-install=true

which tells the application to get its configuration from the .properties and XML files in the Oracle ATG Web Commerce installation.

In a standalone EAR file, instead of using the Commerce installation properties, the ATG-INF directory contains directories corresponding to the Oracle ATG Web Commerce modules included in the application. These directories store the configuration data for the modules, making the EAR file totally self-contained.

Additionally, In a standalone EAR,
the atg_bootstrap.war/WEB-INF/ATG-INF directory contains a home/localconfig subdirectory, which replicates the localconfig directory in the Oracle ATG Web Commerce installation. This localconfig directory is added to the application’s configuration path, so that any settings stored in localconfig in the Oracle ATG Web Commerce installation are also used by the application.

Therefore, you can deploy a standalone EAR on a machine that does not have an Oracle ATG Web Commerce installation, although your ability to modify the application without rebuilding the EAR file (which requires an Oracle ATG Web Commerce installation) is limited.

• Output Files and ATG-Data

Development-mode EAR files write output files to the Oracle ATG Web Commerce installation. For example, log files are written by default to the <ATG10dir>/home/logs directory.

When a standalone EAR file first starts up, it creates an ATG-Data directory. The ATG-Data directory contains subdirectories logs, pagebuild, and data. The ATG-Data directory also contains a localconfig subdirectory that is the last entry in the configuration path.

By default, the ATG-Data directory is created in the current working directory of the Java process. If the JVM starts up in different directories, it creates ATG-Data directories there as well. To specify a location for the directory, set the atg.dynamo-data-dir system property.
For example: java <arguments>  -Datg.dynamo.data-dir=/var/data/ATG-Data/

Nucleus-Based Application Structures

Each EAR file built by runAssembler includes the following J2EE modules:

• atg_bootstrap_ejb.jar: This module contains a single session EJB. The EJB’s class loader is used to load the Oracle ATG Web Commerce classes needed by the application. These classes are stored in the lib directory (at the top level of the EAR file).
• atg_bootstrap.war: This module starts up Nucleus and runs the servlet pipeline.