org.springframework.test.context.support
Class DelegatingSmartContextLoader

java.lang.Object
  org.springframework.test.context.support.DelegatingSmartContextLoader

All Implemented Interfaces:

ContextLoader, SmartContextLoader

public class DelegatingSmartContextLoader
extends Object
implements SmartContextLoader

DelegatingSmartContextLoader is an implementation of the SmartContextLoader SPI that delegates to a set of candidate SmartContextLoaders (i.e., GenericXmlContextLoader and AnnotationConfigContextLoader) 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, DelegatingSmartContextLoader will be used as the default loader, thus providing automatic support for either XML configuration files or configuration classes, but not both simultaneously.

Since:

3.1

Author:

Sam Brannen

See Also:

SmartContextLoader, GenericXmlContextLoader, AnnotationConfigContextLoader

Constructor Summary

DelegatingSmartContextLoader()

Method Summary

ApplicationContext	loadContext(MergedContextConfiguration mergedConfig) Delegates to an appropriate candidate SmartContextLoader to load an ApplicationContext.
ApplicationContext	loadContext(String... locations) DelegatingSmartContextLoader 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) DelegatingSmartContextLoader 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

DelegatingSmartContextLoader

public DelegatingSmartContextLoader()

Method Detail

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 GenericXmlContextLoader and AnnotationConfigContextLoader. Specifically, the delegation algorithm is as follows:

• If the resource locations or configuration 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, GenericXmlContextLoader will be allowed to process the configuration in order to detect default resource locations. If GenericXmlContextLoader detects default resource locations, an info message will be logged.
• Subsequently, AnnotationConfigContextLoader will be allowed to process the configuration in order to detect default configuration classes. If AnnotationConfigContextLoader 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 configuration classes

IllegalStateException - if GenericXmlContextLoader detects default configuration classes; if AnnotationConfigContextLoader 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 GenericXmlContextLoader and AnnotationConfigContextLoader. Specifically, the delegation algorithm is as follows:

• If the resource locations in the supplied MergedContextConfiguration are not empty and the configuration classes are empty, GenericXmlContextLoader will load the ApplicationContext.
• If the configuration classes in the supplied MergedContextConfiguration are not empty and the resource locations are empty, AnnotationConfigContextLoader 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), org.springframework.context.annotation.AnnotationConfigUtils#registerAnnotationConfigProcessors(), MergedContextConfiguration.getActiveProfiles(), ConfigurableApplicationContext.getEnvironment()

processLocations

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

DelegatingSmartContextLoader 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 ApplicationContext loadContext(String... locations)
                               throws Exception

DelegatingSmartContextLoader 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