org.apache.orb.config
Class DefaultLoader

java.lang.Object
  |
  +--org.apache.orb.config.DefaultLoader

All Implemented Interfaces:

org.apache.avalon.framework.activity.Disposable, ORBLoader

public class DefaultLoader

extends java.lang.Object

implements ORBLoader, org.apache.avalon.framework.activity.Disposable

The DefaultLoader provides support for the configuration of a new ORB instance based on default and supplied properties, and lifecycle processing of pluggable Initializers encountered during the configuration process. The implementation also handles the decommissioning of initializers as part of loader disposal.

Property Management

The property set profile for an ORB instance is created based on command line arguments, supplied properties, and an optional embedded configuration.

Property resolution.
Source	Description
args	Property declarations supplied under the init method take precedence. The args array is passed to the Configuration for resolution.
properties	The properties argument to the init method is the second source of property declarations. The DefaultLoader uses the properties argument to establish a new instance that is populated with additional properties based on the DefaultLoader default properties resource, and properties declared under an embedded configuration value.
configuration	A Configuration value may be embeded in the supplied Properties value under the "CONFIGURATION" key. Properties declared in the configuration instance that are recognized by the loader are detailed here. <property name="propertyName" value="propertyValue"/> <property name="propertyName" file="fileName"/> <initializer class="org.apache.pss.Initializer" name="pss"/>
defaults	A set of static default properties are used to suppliment the user defined properties. Default properties are contained in the org/apache/orb/config/orb.properties and org/apache/orb/config/DefaultLoader.xml configuration resources bundeled in the distribution jar file.

Embedded Resources

Resources required to manage pluggable component lifecycle handling are provided to the loader using special keyed values. Keys and the associated values are described in the following table.

Embedded Avalon Resources.
Key	Description
LOGGER	The logging channel to be assigned to the ORB. The logger is used as the relative root when creatiing and assigning logging channels to pluggable initializers.
CONFIGURATION	A configuration instance that may be used to supply supplimentary property declarations and initializers configuration blocks. Initializers that implement the Avalon Cascading interface will be supplied with its configuration during initializer loading.
CONTEXT	The Context is an application context that will be supplied to any initializers that implement the Contextualizable interface.

Logging Catagory Management

The logger supplied to the loader under the embedded properties LOGGER key is assigned as the root logging catagory for the ORB. Catagories for initializers are created as child catagories. If the supplied logger has the catagory name of demo.orb, an initializer catagory for PSS would be demo.orb.pss. Initializer sub-catagories are resolved from the supplied configuration. The DefaultLoader locates an initializer declaration based on an initilizer element with a class attribute value matching that initializer implementation class name. The name attribute value is used as the logging channel sub-catagory name.

     <initializer class="org.apache.pss.Initializer" name="pss"/>
 

Example Usage

The following code fragment demonstrates the creation of a new ORB instance using embedded resources and the DefaultLoader class.

       Properties properties = new Properties();

       // declare the ORB and Singleton implementations

       properties.setProperty( "org.omg.CORBA.ORBClass",
         "org.openorb.orb.core.ORB" );
       properties.setProperty("org.omg.CORBA.ORBSingletonClass",
         "org.openorb.orb.core.ORBSingleton" );

       
          // declare the loader that will be instatiated by the ORB

       properties.setProperty("openorb.ORBLoader",
         "org.apache.orb.config.DefaultLoader");

       
         // add the embedded configuration, logger and context resources

       properties.put( "CONFIGURATION", m_config );
       properties.put( "LOGGER", getLogger().getChildLogger("orb") );
       properties.put( "CONTEXT", m_context );

       // create the ORB

       orb = ORB.init( m_args, properties );
 

Author:

Stephen McConnell

Constructor Summary

DefaultLoader()

Method Summary

java.lang.reflect.Constructor	classConstructor(java.lang.String key, java.lang.String defl, java.lang.Class[] args) Creation of a class constructor.
java.lang.Object	constructClass(java.lang.String prop_key, java.lang.String defl, java.lang.Object[] args) This operation is used to load a class with the given property name and default class name.
java.lang.Object	constructClass(java.lang.String prop_key, java.lang.String defl, java.lang.Object[] args, java.lang.Class[] args_t) This operation is used to load a class with the given property name and default class name.
void	display_configuration() This operation is used to display an OpenORB configuration.
void	display_configuration(org.apache.avalon.framework.logger.Logger logger) This operation is used to display an OpenORB configuration.
void	dispose() Called by the ORB during shutdown enabling the initalizer to clean up.
boolean	getBooleanProperty(java.lang.String name) Get the boolean property with the given name.
boolean	getBooleanProperty(java.lang.String name, boolean defl) Get the boolean property with the given name.
java.lang.Class	getClassProperty(java.lang.String name) Get the integer property with the given name.
java.lang.Class	getClassProperty(java.lang.String name, java.lang.Class defl) Get the Class object property with the given name.
java.lang.Class	getClassProperty(java.lang.String name, java.lang.String defl) Get the Class object property with the given name.
static java.util.Properties	getDefaultProperties() Returns the system wide default ORB properties
int	getIntProperty(java.lang.String name) Get the integer property with the given name.
int	getIntProperty(java.lang.String name, int defl) Get the integer property with the given name.
Property	getProperty(java.lang.String name) Get the Property object with the given name.
java.lang.String	getStringProperty(java.lang.String name) Get the string property with the given name.
java.lang.String	getStringProperty(java.lang.String name, java.lang.String defl) Get the string property with the given name.
java.net.URL	getURLProperty(java.lang.String name) Get the URL property with the given name.
java.net.URL	getURLProperty(java.lang.String name, java.net.URL defl) Get the URL property with the given name.
void	init(java.lang.String[] args, java.util.Properties props, ORB orb) ORB Initialization.
void	load_kernel() This operation is used to load the OpenORB kernel.
void	mergeProperties(java.io.File root, org.apache.avalon.framework.configuration.Configuration config, java.util.Properties properties) Adds property declarations to the supplied Properties argument from the supplied configuration.
java.util.Iterator	properties(java.lang.String name) Iterate over property values with the specified prefix.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DefaultLoader

public DefaultLoader()

Method Detail

load_kernel

public void load_kernel()

This operation is used to load the OpenORB kernel.

Depending on the property openorb.server.enable ( default true ) and openorb.client.enable ( default true ) this method instantiates the ServerCPCManager and the ClientCPCMamager. This instantiation is pluggable as it is driven by properties:

• openorb.server.ServerManagerClass ( default org.openorb.orb.net.ServerManagerImpl )
• openorb.client.ClientManagerClass ( default org.openorb.orb.net.ClientManagerImpl )

The interface of the ServerCPCManager is defined by the org.openorb.orb.net.ServerManager interface and by the org.openorb.orb.net.ClientManager interface for the ClientCPCManager respectively.

The property openorb.dynany.enable (default true) allows to avoid loading the DynAnyFactory if it is not used by the application. This can save you some amount memory.

The property openorb.client.enable also decides whether to load the initiali references ORBPolicyManager and PolicyCurrent into the ORB.

init

public void init(java.lang.String[] args,
                 java.util.Properties props,
                 ORB orb)

ORB Initialization.

Specified by:

init in interface ORBLoader

Parameters:

args - command line arguments

props - properties argument

orb - the ORB instance

display_configuration

public void display_configuration()

This operation is used to display an OpenORB configuration.

Specified by:

display_configuration in interface ORBLoader

display_configuration

public void display_configuration(org.apache.avalon.framework.logger.Logger logger)

This operation is used to display an OpenORB configuration.

Parameters:

logger - the logging channel to direct display of properties

properties

public java.util.Iterator properties(java.lang.String name)

Iterate over property values with the specified prefix.

Specified by:

properties in interface ORBLoader

Parameters:

name - parent of properties. Properies of the form name + "." + xxx are returned, where xxx can be anything. May be null to iterate over all properies.

Returns:

unmodifiable iterator over the name's decendants. This iterator returns objects of type Property.

getProperty

public Property getProperty(java.lang.String name)

Get the Property object with the given name.

Specified by:

getProperty in interface ORBLoader

Parameters:

name - the property name.

Returns:

Property the named property

getStringProperty

public java.lang.String getStringProperty(java.lang.String name,
                                          java.lang.String defl)

Get the string property with the given name.

Specified by:

getStringProperty in interface ORBLoader

Parameters:

name - the property name.

defl - default value to use if property not found.

Returns:

String the property value

getStringProperty

public java.lang.String getStringProperty(java.lang.String name)
                                   throws PropertyNotFoundException

Get the string property with the given name.

Specified by:

getStringProperty in interface ORBLoader

Parameters:

name - the property name.

Returns:

String the property value

Throws:

PropertyNotFoundException - the property cannot be found.

getIntProperty

public int getIntProperty(java.lang.String name,
                          int defl)

Get the integer property with the given name.

Specified by:

getIntProperty in interface ORBLoader

Parameters:

name - the property name.

defl - default value to use if property not found.

Returns:

int the property value

getIntProperty

public int getIntProperty(java.lang.String name)
                   throws PropertyNotFoundException

Get the integer property with the given name.

Specified by:

getIntProperty in interface ORBLoader

Parameters:

name - the property name.

Returns:

int the property value

Throws:

PropertyNotFoundException - the property cannot be found.

getBooleanProperty

public boolean getBooleanProperty(java.lang.String name,
                                  boolean defl)

Get the boolean property with the given name.

Specified by:

getBooleanProperty in interface ORBLoader

Parameters:

name - the property name.

defl - default value to use if property not found.

Returns:

boolean the property value

getBooleanProperty

public boolean getBooleanProperty(java.lang.String name)
                           throws PropertyNotFoundException

Get the boolean property with the given name.

Specified by:

getBooleanProperty in interface ORBLoader

Parameters:

name - the property name.

Returns:

boolean the property value

Throws:

PropertyNotFoundException - the property cannot be found.

getURLProperty

public java.net.URL getURLProperty(java.lang.String name,
                                   java.net.URL defl)

Get the URL property with the given name.

Specified by:

getURLProperty in interface ORBLoader

Parameters:

name - the property name.

defl - default value to use if property not found.

Returns:

URL the property value

getURLProperty

public java.net.URL getURLProperty(java.lang.String name)
                            throws PropertyNotFoundException

Get the URL property with the given name.

Specified by:

getURLProperty in interface ORBLoader

Parameters:

name - the property name.

Returns:

URL the property value

Throws:

PropertyNotFoundException - the property cannot be found.

getClassProperty

public java.lang.Class getClassProperty(java.lang.String name,
                                        java.lang.Class defl)

Get the Class object property with the given name.

Specified by:

getClassProperty in interface ORBLoader

Parameters:

name - the property name.

defl - default value to use if property not found.

Returns:

Class the property value

getClassProperty

public java.lang.Class getClassProperty(java.lang.String name,
                                        java.lang.String defl)

Get the Class object property with the given name.

Specified by:

getClassProperty in interface ORBLoader

Parameters:

name - the property name.

defl - String name of default value to use if property not found.

Returns:

Class the property value

getClassProperty

public java.lang.Class getClassProperty(java.lang.String name)
                                 throws PropertyNotFoundException

Get the integer property with the given name.

Specified by:

getClassProperty in interface ORBLoader

Parameters:

name - the property name.

Returns:

Class the property value

Throws:

PropertyNotFoundException - the property cannot be found.

constructClass

public java.lang.Object constructClass(java.lang.String prop_key,
                                       java.lang.String defl,
                                       java.lang.Object[] args)
                                throws java.lang.reflect.InvocationTargetException

This operation is used to load a class with the given property name and default class name.

Specified by:

constructClass in interface ORBLoader

Parameters:

prop_key - Property name, this string property holds the name of the class. May be null if no property is used.

defl - Default class name. Used if the named property is not found. May be null to indicate no load should be performed if property is missing.

args - arguments to constructor. If any constructor arguments are primitive types then the four argument version of this function must be used.

Returns:

the newly constructed object, or null if the property value is set to the empty string.

Throws:

java.lang.reflect.InvocationTargetException - an exception occoured in the constructor.

constructClass

public java.lang.Object constructClass(java.lang.String prop_key,
                                       java.lang.String defl,
                                       java.lang.Object[] args,
                                       java.lang.Class[] args_t)
                                throws java.lang.reflect.InvocationTargetException

This operation is used to load a class with the given property name and default class name.

Specified by:

constructClass in interface ORBLoader

Parameters:

prop_key - Property name, this string property holds the name of the class. May be null if no property is used.

defl - Default class name. Used if the named property is not found. May be null to indicate no load should be performed if property is missing.

args - arguments to constructor. If any constructor arguments are primitive types then the four argument version of this function must be used.

args_t - types of onstructor arguments. If any of these are null they will be determined from getClass on the matching arg. Length must match length of args.

Returns:

the newly constructed object, or null if the property value is set to the empty string.

Throws:

java.lang.reflect.InvocationTargetException - an exception occoured in the constructor.

classConstructor

public java.lang.reflect.Constructor classConstructor(java.lang.String key,
                                                      java.lang.String defl,
                                                      java.lang.Class[] args)

Creation of a class constructor.

Specified by:

classConstructor in interface ORBLoader

Parameters:

key - property key

defl - default value

args - constructor arguments

Returns:

java.lang.reflect.Constructor the constructor

getDefaultProperties

public static java.util.Properties getDefaultProperties()

Returns the system wide default ORB properties

Returns:

java.util.Properties default properties

mergeProperties

public void mergeProperties(java.io.File root,
                            org.apache.avalon.framework.configuration.Configuration config,
                            java.util.Properties properties)
                     throws java.lang.Exception

Adds property declarations to the supplied Properties argument from the supplied configuration. Any configuration elements of the following form will be translated to property values and added to the property set.

   <any-containing-element>
      <property name="myProperty" value="someValue"/>
      <property name="info" file="eggs.xml"/>
   </any-containing-element>
 

Parameters:

root - the file path to be used in resolution of property element in the configuration that contain 'file' attributes as the property value

config - a configuration containing 'property' element declarations

properties - the properties to merge

Throws:

java.lang.Exception - if an merge error occurs

dispose

public void dispose()

Called by the ORB during shutdown enabling the initalizer to clean up.

Specified by:

dispose in interface org.apache.avalon.framework.activity.Disposable