Package org.apache.commons.configuration2.beanutils

Interface BeanDeclaration

All Known Implementing Classes:

CombinedBeanDeclaration, ConfigurationDeclaration, XMLBeanDeclaration

public interface BeanDeclaration

Definition of an interface for declaring a bean in a configuration file.

Commons Configurations allows to define beans (i.e. simple Java objects) in configuration files, which can be created at runtime. This is especially useful if you program against interfaces and want to define the concrete implementation class is a configuration file.

This interface defines methods for retrieving all information about a bean that should be created from a configuration file, e.g. the bean's properties or the factory to use for creating the instance. With different implementations different "layouts" of bean declarations can be supported. For instance if an XML configuration file is used, all features of XML (e.g. attributes, nested elements) can be used to define the bean. In a properties file the declaration format is more limited. The purpose of this interface is to abstract from the concrete declaration format.

Since:

1.3

Version:

$Id: BeanDeclaration.java 1624601 2014-09-12 18:04:36Z oheger $

Author:

Commons Configuration team

Method Summary

Modifier and Type	Method	Description
java.lang.String	getBeanClassName()	Returns the name of the bean class, from which an instance is to be created.
java.lang.String	getBeanFactoryName()	Returns the name of the BeanFactory that should be used for creating the bean instance.
java.lang.Object	getBeanFactoryParameter()	Here an arbitrary object can be returned that will be passed to the bean factory.
java.util.Map<java.lang.String,java.lang.Object>	getBeanProperties()	Returns a map with properties that should be initialized on the newly created bean.
java.util.Collection<ConstructorArg>	getConstructorArgs()	Returns a collection with constructor arguments.
java.util.Map<java.lang.String,java.lang.Object>	getNestedBeanDeclarations()	Returns a map with declarations for beans that should be set as properties of the newly created bean.

Method Detail

getBeanFactoryName

java.lang.String getBeanFactoryName()

Returns the name of the BeanFactory that should be used for creating the bean instance. This can be null, then a default factory will be used.

Returns:

the name of the bean factory

getBeanFactoryParameter

java.lang.Object getBeanFactoryParameter()

Here an arbitrary object can be returned that will be passed to the bean factory. Its meaning is not further specified. The purpose of this additional parameter is to support a further configuration of the bean factory that can be placed directly at the bean declaration.

Returns:

a parameter for the bean factory

getBeanClassName

java.lang.String getBeanClassName()

Returns the name of the bean class, from which an instance is to be created. This value must be defined unless a default class is provided for the bean creation operation.

Returns:

the name of the bean class

getBeanProperties

java.util.Map<java.lang.String,java.lang.Object> getBeanProperties()

Returns a map with properties that should be initialized on the newly created bean. The map's keys are the names of the properties; the corresponding values are the properties' values. The return value can be null if no properties should be set.

Returns:

a map with properties to be initialized

getNestedBeanDeclarations

java.util.Map<java.lang.String,java.lang.Object> getNestedBeanDeclarations()

Returns a map with declarations for beans that should be set as properties of the newly created bean. This allows for complex initialization scenarios: a bean for a bean that contains complex properties (e.g. other beans) can have nested declarations for defining these complex properties. The returned map's key are the names of the properties to initialize. The values are either BeanDeclaration implementations or collections thereof. They will be treated like this declaration (in a recursive manner), and the resulting beans are assigned to the corresponding properties.

Returns:

a map with nested bean declarations

getConstructorArgs

java.util.Collection<ConstructorArg> getConstructorArgs()

Returns a collection with constructor arguments. This data is used to determine the constructor of the bean class to be invoked. The values of the arguments are passed to the constructor. An implementation can return null or an empty collection; then the standard constructor of the bean class is called.

Returns:

a collection with the arguments to be passed to the bean class's constructor