/*
* Copyright 2002-2016 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.web.context.support;
import java.util.Arrays;
import java.util.LinkedHashSet;
import java.util.Set;
import org.springframework.beans.factory.support.BeanNameGenerator;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.context.annotation.AnnotatedBeanDefinitionReader;
import org.springframework.context.annotation.AnnotationConfigRegistry;
import org.springframework.context.annotation.AnnotationConfigUtils;
import org.springframework.context.annotation.ClassPathBeanDefinitionScanner;
import org.springframework.context.annotation.ScopeMetadataResolver;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
import org.springframework.web.context.ContextLoader;
/**
* {@link org.springframework.web.context.WebApplicationContext WebApplicationContext}
* implementation which accepts annotated classes as input - in particular
* {@link org.springframework.context.annotation.Configuration @Configuration}-annotated
* classes, but also plain {@link org.springframework.stereotype.Component @Component}
* classes and JSR-330 compliant classes using {@code javax.inject} annotations. Allows
* for registering classes one by one (specifying class names as config location) as well
* as for classpath scanning (specifying base packages as config location).
*
* <p>This is essentially the equivalent of
* {@link org.springframework.context.annotation.AnnotationConfigApplicationContext
* AnnotationConfigApplicationContext} for a web environment.
*
* <p>To make use of this application context, the
* {@linkplain ContextLoader#CONTEXT_CLASS_PARAM "contextClass"} context-param for
* ContextLoader and/or "contextClass" init-param for FrameworkServlet must be set to
* the fully-qualified name of this class.
*
* <p>As of Spring 3.1, this class may also be directly instantiated and injected into
* Spring's {@code DispatcherServlet} or {@code ContextLoaderListener} when using the
* new {@link org.springframework.web.WebApplicationInitializer WebApplicationInitializer}
* code-based alternative to {@code web.xml}. See its Javadoc for details and usage examples.
*
* <p>Unlike {@link XmlWebApplicationContext}, no default configuration class locations
* are assumed. Rather, it is a requirement to set the
* {@linkplain ContextLoader#CONFIG_LOCATION_PARAM "contextConfigLocation"}
* context-param for {@link ContextLoader} and/or "contextConfigLocation" init-param for
* FrameworkServlet. The param-value may contain both fully-qualified
* class names and base packages to scan for components. See {@link #loadBeanDefinitions}
* for exact details on how these locations are processed.
*
* <p>As an alternative to setting the "contextConfigLocation" parameter, users may
* implement an {@link org.springframework.context.ApplicationContextInitializer
* ApplicationContextInitializer} and set the
* {@linkplain ContextLoader#CONTEXT_INITIALIZER_CLASSES_PARAM "contextInitializerClasses"}
* context-param / init-param. In such cases, users should favor the {@link #refresh()}
* and {@link #scan(String...)} methods over the {@link #setConfigLocation(String)}
* method, which is primarily for use by {@code ContextLoader}.
*
* <p>Note: In case of multiple {@code @Configuration} classes, later {@code @Bean}
* definitions will override ones defined in earlier loaded files. This can be leveraged
* to deliberately override certain bean definitions via an extra Configuration class.
*
* @author Chris Beams
* @author Juergen Hoeller
* @since 3.0
* @see org.springframework.context.annotation.AnnotationConfigApplicationContext
*/
public class AnnotationConfigWebApplicationContext extends AbstractRefreshableWebApplicationContext
implements AnnotationConfigRegistry {
private BeanNameGenerator beanNameGenerator;
private ScopeMetadataResolver scopeMetadataResolver;
private final Set<Class<?>> annotatedClasses = new LinkedHashSet<>();
private final Set<String> basePackages = new LinkedHashSet<>();
/**
* Set a custom {@link BeanNameGenerator} for use with {@link AnnotatedBeanDefinitionReader}
* and/or {@link ClassPathBeanDefinitionScanner}.
* <p>Default is {@link org.springframework.context.annotation.AnnotationBeanNameGenerator}.
* @see AnnotatedBeanDefinitionReader#setBeanNameGenerator
* @see ClassPathBeanDefinitionScanner#setBeanNameGenerator
*/
public void setBeanNameGenerator(BeanNameGenerator beanNameGenerator) {
this.beanNameGenerator = beanNameGenerator;
}
/**
* Return the custom {@link BeanNameGenerator} for use with {@link AnnotatedBeanDefinitionReader}
* and/or {@link ClassPathBeanDefinitionScanner}, if any.
*/
protected BeanNameGenerator getBeanNameGenerator() {
return this.beanNameGenerator;
}
/**
* Set a custom {@link ScopeMetadataResolver} for use with {@link AnnotatedBeanDefinitionReader}
* and/or {@link ClassPathBeanDefinitionScanner}.
* <p>Default is an {@link org.springframework.context.annotation.AnnotationScopeMetadataResolver}.
* @see AnnotatedBeanDefinitionReader#setScopeMetadataResolver
* @see ClassPathBeanDefinitionScanner#setScopeMetadataResolver
*/
public void setScopeMetadataResolver(ScopeMetadataResolver scopeMetadataResolver) {
this.scopeMetadataResolver = scopeMetadataResolver;
}
/**
* Return the custom {@link ScopeMetadataResolver} for use with {@link AnnotatedBeanDefinitionReader}
* and/or {@link ClassPathBeanDefinitionScanner}, if any.
*/
protected ScopeMetadataResolver getScopeMetadataResolver() {
return this.scopeMetadataResolver;
}
/**
* Register one or more annotated classes to be processed.
* <p>Note that {@link #refresh()} must be called in order for the context
* to fully process the new classes.
* @param annotatedClasses one or more annotated classes,
* e.g. {@link org.springframework.context.annotation.Configuration @Configuration} classes
* @see #scan(String...)
* @see #loadBeanDefinitions(DefaultListableBeanFactory)
* @see #setConfigLocation(String)
* @see #refresh()
*/
public void register(Class<?>... annotatedClasses) {
Assert.notEmpty(annotatedClasses, "At least one annotated class must be specified");
this.annotatedClasses.addAll(Arrays.asList(annotatedClasses));
}
/**
* Perform a scan within the specified base packages.
* <p>Note that {@link #refresh()} must be called in order for the context
* to fully process the new classes.
* @param basePackages the packages to check for annotated classes
* @see #loadBeanDefinitions(DefaultListableBeanFactory)
* @see #register(Class...)
* @see #setConfigLocation(String)
* @see #refresh()
*/
public void scan(String... basePackages) {
Assert.notEmpty(basePackages, "At least one base package must be specified");
this.basePackages.addAll(Arrays.asList(basePackages));
}
/**
* Register a {@link org.springframework.beans.factory.config.BeanDefinition} for
* any classes specified by {@link #register(Class...)} and scan any packages
* specified by {@link #scan(String...)}.
* <p>For any values specified by {@link #setConfigLocation(String)} or
* {@link #setConfigLocations(String[])}, attempt first to load each location as a
* class, registering a {@code BeanDefinition} if class loading is successful,
* and if class loading fails (i.e. a {@code ClassNotFoundException} is raised),
* assume the value is a package and attempt to scan it for annotated classes.
* <p>Enables the default set of annotation configuration post processors, such that
* {@code @Autowired}, {@code @Required}, and associated annotations can be used.
* <p>Configuration class bean definitions are registered with generated bean
* definition names unless the {@code value} attribute is provided to the stereotype
* annotation.
* @param beanFactory the bean factory to load bean definitions into
* @see #register(Class...)
* @see #scan(String...)
* @see #setConfigLocation(String)
* @see #setConfigLocations(String[])
* @see AnnotatedBeanDefinitionReader
* @see ClassPathBeanDefinitionScanner
*/
@Override
protected void loadBeanDefinitions(DefaultListableBeanFactory beanFactory) {
AnnotatedBeanDefinitionReader reader = getAnnotatedBeanDefinitionReader(beanFactory);
ClassPathBeanDefinitionScanner scanner = getClassPathBeanDefinitionScanner(beanFactory);
BeanNameGenerator beanNameGenerator = getBeanNameGenerator();
if (beanNameGenerator != null) {
reader.setBeanNameGenerator(beanNameGenerator);
scanner.setBeanNameGenerator(beanNameGenerator);
beanFactory.registerSingleton(AnnotationConfigUtils.CONFIGURATION_BEAN_NAME_GENERATOR, beanNameGenerator);
}
ScopeMetadataResolver scopeMetadataResolver = getScopeMetadataResolver();
if (scopeMetadataResolver != null) {
reader.setScopeMetadataResolver(scopeMetadataResolver);
scanner.setScopeMetadataResolver(scopeMetadataResolver);
}
if (!this.annotatedClasses.isEmpty()) {
if (logger.isInfoEnabled()) {
logger.info("Registering annotated classes: [" +
StringUtils.collectionToCommaDelimitedString(this.annotatedClasses) + "]");
}
reader.register(this.annotatedClasses.toArray(new Class<?>[this.annotatedClasses.size()]));
}
if (!this.basePackages.isEmpty()) {
if (logger.isInfoEnabled()) {
logger.info("Scanning base packages: [" +
StringUtils.collectionToCommaDelimitedString(this.basePackages) + "]");
}
scanner.scan(this.basePackages.toArray(new String[this.basePackages.size()]));
}
String[] configLocations = getConfigLocations();
if (configLocations != null) {
for (String configLocation : configLocations) {
try {
Class<?> clazz = getClassLoader().loadClass(configLocation);
if (logger.isInfoEnabled()) {
logger.info("Successfully resolved class for [" + configLocation + "]");
}
reader.register(clazz);
}
catch (ClassNotFoundException ex) {
if (logger.isDebugEnabled()) {
logger.debug("Could not load class for config location [" + configLocation +
"] - trying package scan. " + ex);
}
int count = scanner.scan(configLocation);
if (logger.isInfoEnabled()) {
if (count == 0) {
logger.info("No annotated classes found for specified class/package [" + configLocation + "]");
}
else {
logger.info("Found " + count + " annotated classes in package [" + configLocation + "]");
}
}
}
}
}
}
/**
* Build an {@link AnnotatedBeanDefinitionReader} for the given bean factory.
* <p>This should be pre-configured with the {@code Environment} (if desired)
* but not with a {@code BeanNameGenerator} or {@code ScopeMetadataResolver} yet.
* @param beanFactory the bean factory to load bean definitions into
* @since 4.1.9
* @see #getEnvironment()
* @see #getBeanNameGenerator()
* @see #getScopeMetadataResolver()
*/
protected AnnotatedBeanDefinitionReader getAnnotatedBeanDefinitionReader(DefaultListableBeanFactory beanFactory) {
return new AnnotatedBeanDefinitionReader(beanFactory, getEnvironment());
}
/**
* Build a {@link ClassPathBeanDefinitionScanner} for the given bean factory.
* <p>This should be pre-configured with the {@code Environment} (if desired)
* but not with a {@code BeanNameGenerator} or {@code ScopeMetadataResolver} yet.
* @param beanFactory the bean factory to load bean definitions into
* @since 4.1.9
* @see #getEnvironment()
* @see #getBeanNameGenerator()
* @see #getScopeMetadataResolver()
*/
protected ClassPathBeanDefinitionScanner getClassPathBeanDefinitionScanner(DefaultListableBeanFactory beanFactory) {
return new ClassPathBeanDefinitionScanner(beanFactory, true, getEnvironment());
}
}