org.springframework.test.context.support

Class AbstractDelegatingSmartContextLoader

java.lang.Object

org.springframework.test.context.support.AbstractDelegatingSmartContextLoader

All Implemented Interfaces:

ContextLoader, SmartContextLoader

Direct Known Subclasses:

DelegatingSmartContextLoader, WebDelegatingSmartContextLoader

public abstract class AbstractDelegatingSmartContextLoader
extends Object
implements SmartContextLoader

AbstractDelegatingSmartContextLoader serves as an abstract base class for implementations of the SmartContextLoader SPI that delegate to a set of candidate SmartContextLoaders (i.e., one that supports XML configuration files and one that supports annotated classes) to determine which context loader is appropriate for a given test class's configuration. Each candidate is given a chance to process the ContextConfigurationAttributes for each class in the test class hierarchy that is annotated with @ContextConfiguration, and the candidate that supports the merged, processed configuration will be used to actually load the context.

Placing an empty @ContextConfiguration annotation on a test class signals that default resource locations (i.e., XML configuration files) or default configuration classes should be detected. Furthermore, if a specific ContextLoader or SmartContextLoader is not explicitly declared via @ContextConfiguration, a concrete subclass of AbstractDelegatingSmartContextLoader will be used as the default loader, thus providing automatic support for either XML configuration files or annotated classes, but not both simultaneously.

As of Spring 3.2, a test class may optionally declare neither XML configuration files nor annotated classes and instead declare only application context initializers. In such cases, an attempt will still be made to detect defaults, but their absence will not result in an exception.

Since:

3.2

Author:

Sam Brannen

See Also:

SmartContextLoader

Constructor Summary

Constructors

Constructor and Description
AbstractDelegatingSmartContextLoader()

Method Summary

Modifier and Type	Method and Description
protected abstract SmartContextLoader	getAnnotationConfigLoader() Get the delegate SmartContextLoader that supports annotated classes.
protected abstract SmartContextLoader	getXmlLoader() Get the delegate SmartContextLoader that supports XML configuration files.
ApplicationContext	loadContext(MergedContextConfiguration mergedConfig) Delegates to an appropriate candidate SmartContextLoader to load an ApplicationContext.
ApplicationContext	loadContext(String... locations) AbstractDelegatingSmartContextLoader does not support the ContextLoader.loadContext(String...) method.
void	processContextConfiguration(ContextConfigurationAttributes configAttributes) Delegates to candidate SmartContextLoaders to process the supplied ContextConfigurationAttributes.
String[]	processLocations(Class<?> clazz, String... locations) AbstractDelegatingSmartContextLoader does not support the ContextLoader.processLocations(Class, String...) method.

Methods inherited from class java.lang.Object

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

Constructor Detail

AbstractDelegatingSmartContextLoader

public AbstractDelegatingSmartContextLoader()

Method Detail

getXmlLoader

protected abstract SmartContextLoader getXmlLoader()

Get the delegate SmartContextLoader that supports XML configuration files.

getAnnotationConfigLoader

protected abstract SmartContextLoader getAnnotationConfigLoader()

Get the delegate SmartContextLoader that supports annotated classes.

processContextConfiguration

public void processContextConfiguration(ContextConfigurationAttributes configAttributes)

Delegates to candidate SmartContextLoaders to process the supplied ContextConfigurationAttributes.

Delegation is based on explicit knowledge of the implementations of the default loaders for XML configuration files and annotated classes. Specifically, the delegation algorithm is as follows:

• If the resource locations or annotated classes in the supplied ContextConfigurationAttributes are not empty, the appropriate candidate loader will be allowed to process the configuration as is, without any checks for detection of defaults.
• Otherwise, the XML-based loader will be allowed to process the configuration in order to detect default resource locations. If the XML-based loader detects default resource locations, an info message will be logged.
• Subsequently, the annotation-based loader will be allowed to process the configuration in order to detect default configuration classes. If the annotation-based loader detects default configuration classes, an info message will be logged.

Specified by:

processContextConfiguration in interface SmartContextLoader

Parameters:

configAttributes - the context configuration attributes to process

Throws:

IllegalArgumentException - if the supplied configuration attributes are null, or if the supplied configuration attributes include both resource locations and annotated classes

IllegalStateException - if the XML-based loader detects default configuration classes; if the annotation-based loader detects default resource locations; if neither candidate loader detects defaults for the supplied context configuration; or if both candidate loaders detect defaults for the supplied context configuration

loadContext

public ApplicationContext loadContext(MergedContextConfiguration mergedConfig)
                               throws Exception

Delegates to an appropriate candidate SmartContextLoader to load an ApplicationContext.

Delegation is based on explicit knowledge of the implementations of the default loaders for XML configuration files and annotated classes. Specifically, the delegation algorithm is as follows:

• If the resource locations in the supplied MergedContextConfiguration are not empty and the annotated classes are empty, the XML-based loader will load the ApplicationContext.
• If the annotated classes in the supplied MergedContextConfiguration are not empty and the resource locations are empty, the annotation-based loader will load the ApplicationContext.

Specified by:

loadContext in interface SmartContextLoader

Parameters:

mergedConfig - the merged context configuration to use to load the application context

Returns:

a new application context

Throws:

IllegalArgumentException - if the supplied merged configuration is null

IllegalStateException - if neither candidate loader is capable of loading an ApplicationContext from the supplied merged context configuration

Exception - if context loading failed

See Also:

SmartContextLoader.processContextConfiguration(ContextConfigurationAttributes), #registerAnnotationConfigProcessors(org.springframework.beans.factory.support.BeanDefinitionRegistry), MergedContextConfiguration.getActiveProfiles(), ConfigurableApplicationContext.getEnvironment()

processLocations

public final String[] processLocations(Class<?> clazz,
                                       String... locations)

AbstractDelegatingSmartContextLoader does not support the ContextLoader.processLocations(Class, String...) method. Call processContextConfiguration(ContextConfigurationAttributes) instead.

Specified by:

processLocations in interface ContextLoader

Parameters:

clazz - the class with which the locations are associated: used to determine how to process the supplied locations

locations - the unmodified locations to use for loading the application context (can be null or empty)

Returns:

an array of application context resource locations

Throws:

UnsupportedOperationException

loadContext

public final ApplicationContext loadContext(String... locations)
                                     throws Exception

AbstractDelegatingSmartContextLoader does not support the ContextLoader.loadContext(String...) method. Call loadContext(MergedContextConfiguration) instead.

Specified by:

loadContext in interface ContextLoader

Parameters:

locations - the resource locations to use to load the application context

Returns:

a new application context

Throws:

UnsupportedOperationException

Exception - if context loading failed