The ast.properties file is searched for in these locations:

If the ast.properties file is located in the top of the JAR file it is always found and loaded if the JAR file is in the current class path. This is the simplest and most transparent mechanism to locate the ast.properties file.

It is also possible to locate the ast.properties file in a nested directory in a JAR file if this directory is specified in the class path.

If there are multiple ast.properties file located in a JAR file, the first one located is used. All others are ignored.

This is an example of a JAR file that contains the ast.properties file at the top of the JAR file.

jar tf snippets.jar

META-INF/
META-INF/MANIFEST.MF
com/
com/kabira/
com/kabira/snippets/
com/kabira/snippets/components/
com/kabira/snippets/development/
com/kabira/snippets/distributedcomputing/
com/kabira/snippets/highavailability/
com/kabira/snippets/managedobjects/
com/kabira/snippets/management/
com/kabira/snippets/reference/
com/kabira/snippets/transactions/
com/kabira/snippets/vmlifecycle/

...

ast.properties

Component notifiers provide a mechanism to transparently perform component initialization and termination. The user of the component does not need to explicitly initialize or terminate a component.

A notifier is implemented by extending com.kabira.platform.Notifier and overriding the methods are that are needed to perform component initialization and termination. See Example 11.3, “Component notifier” for an example notifier.

//     $Revision: 1.1.2.1 $
package com.kabira.snippets.components;

import com.kabira.platform.component.Notifier;
import com.kabira.platform.component.ComponentException;

/**
 * Component notifier one
 */
public class NotifierOne extends Notifier
{
    @Override
    protected void preConfigurationInitialize()
        throws ComponentException
    {
        try
        {
            //
            //  Resolve configuration class
            //
            Class.forName("com.kabira.snippets.components.Defaults");
        }
        catch (ClassNotFoundException ex)
        {
            new ComponentException("Class resolution failed", ex);
        }

        m_notifierName = getClass().getSimpleName();
        
        System.out.println(m_notifierName + ": - preConfigurationInitialize");
    }

    @Override
    protected void postConfigurationInitialize()
    {
        System.out.println(m_notifierName + ": - postConfigurationInitialize");

    }

    @Override
    protected void preConfigurationTerminate()
    {
        System.out.println(m_notifierName + ": - preConfigurationTerminate");

    }

    @Override
    protected void postConfigurationTerminate()
    {
        System.out.println(m_notifierName + ": - postConfigurationTerminate");
    }

    private String  m_notifierName;
}

Notifiers are created and executed in the order they are specified in the Component-Notifiers property during component initialization. They are executed and released for garbage collection in the reverse order during component termination. Since the same notifier instance is used for initialization and termination, state information can be stored in the notifier during the lifetime of the component for implementation specific reasons.

Component activation fails if:

Components may contain configuration files. The configuration files contained in a component are automatically loaded and activated when a component is initialized. They are loaded and activated in the order they are specified in the Configuration-Files property. The configuration files are deactivated and removed when the component is terminated. They are deactivated and removed in the reverse order from which they were activated during initialization.

Component activation fails if:

Any failures deactivating and removing configuration files during component termination are ignored.