spring AutoConfigurationPackages 源码

  • 2022-08-12
  • 浏览 (459)

springboot AutoConfigurationPackages 代码

文件路径:/spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/AutoConfigurationPackages.java

/*
 * Copyright 2012-2022 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
 *
 *      https://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.boot.autoconfigure;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Set;
import java.util.stream.Stream;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.beans.factory.BeanFactory;
import org.springframework.beans.factory.NoSuchBeanDefinitionException;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.config.ConstructorArgumentValues;
import org.springframework.beans.factory.support.BeanDefinitionRegistry;
import org.springframework.beans.factory.support.RootBeanDefinition;
import org.springframework.boot.context.annotation.DeterminableImports;
import org.springframework.context.annotation.ImportBeanDefinitionRegistrar;
import org.springframework.core.annotation.AnnotationAttributes;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.util.ClassUtils;
import org.springframework.util.StringUtils;

/**
 * Class for storing auto-configuration packages for reference later (e.g. by JPA entity
 * scanner).
 *
 * @author Phillip Webb
 * @author Dave Syer
 * @author Oliver Gierke
 * @since 1.0.0
 */
public abstract class AutoConfigurationPackages {

	private static final Log logger = LogFactory.getLog(AutoConfigurationPackages.class);

	private static final String BEAN = AutoConfigurationPackages.class.getName();

	/**
	 * Determine if the auto-configuration base packages for the given bean factory are
	 * available.
	 * @param beanFactory the source bean factory
	 * @return true if there are auto-config packages available
	 */
	public static boolean has(BeanFactory beanFactory) {
		return beanFactory.containsBean(BEAN) && !get(beanFactory).isEmpty();
	}

	/**
	 * Return the auto-configuration base packages for the given bean factory.
	 * @param beanFactory the source bean factory
	 * @return a list of auto-configuration packages
	 * @throws IllegalStateException if auto-configuration is not enabled
	 */
	public static List<String> get(BeanFactory beanFactory) {
		try {
			return beanFactory.getBean(BEAN, BasePackages.class).get();
		}
		catch (NoSuchBeanDefinitionException ex) {
			throw new IllegalStateException("Unable to retrieve @EnableAutoConfiguration base packages");
		}
	}

	/**
	 * Programmatically registers the auto-configuration package names. Subsequent
	 * invocations will add the given package names to those that have already been
	 * registered. You can use this method to manually define the base packages that will
	 * be used for a given {@link BeanDefinitionRegistry}. Generally it's recommended that
	 * you don't call this method directly, but instead rely on the default convention
	 * where the package name is set from your {@code @EnableAutoConfiguration}
	 * configuration class or classes.
	 * @param registry the bean definition registry
	 * @param packageNames the package names to set
	 */
	public static void register(BeanDefinitionRegistry registry, String... packageNames) {
		if (registry.containsBeanDefinition(BEAN)) {
			addBasePackages(registry.getBeanDefinition(BEAN), packageNames);
		}
		else {
			RootBeanDefinition beanDefinition = new RootBeanDefinition(BasePackages.class);
			beanDefinition.setRole(BeanDefinition.ROLE_INFRASTRUCTURE);
			addBasePackages(beanDefinition, packageNames);
			registry.registerBeanDefinition(BEAN, beanDefinition);
		}
	}

	private static void addBasePackages(BeanDefinition beanDefinition, String[] additionalBasePackages) {
		ConstructorArgumentValues constructorArgumentValues = beanDefinition.getConstructorArgumentValues();
		if (constructorArgumentValues.hasIndexedArgumentValue(0)) {
			String[] existingPackages = (String[]) constructorArgumentValues.getIndexedArgumentValue(0, String[].class)
					.getValue();
			constructorArgumentValues.addIndexedArgumentValue(0,
					Stream.concat(Stream.of(existingPackages), Stream.of(additionalBasePackages)).distinct()
							.toArray(String[]::new));
		}
		else {
			constructorArgumentValues.addIndexedArgumentValue(0, additionalBasePackages);
		}
	}

	/**
	 * {@link ImportBeanDefinitionRegistrar} to store the base package from the importing
	 * configuration.
	 */
	static class Registrar implements ImportBeanDefinitionRegistrar, DeterminableImports {

		@Override
		public void registerBeanDefinitions(AnnotationMetadata metadata, BeanDefinitionRegistry registry) {
			register(registry, new PackageImports(metadata).getPackageNames().toArray(new String[0]));
		}

		@Override
		public Set<Object> determineImports(AnnotationMetadata metadata) {
			return Collections.singleton(new PackageImports(metadata));
		}

	}

	/**
	 * Wrapper for a package import.
	 */
	private static final class PackageImports {

		private final List<String> packageNames;

		PackageImports(AnnotationMetadata metadata) {
			AnnotationAttributes attributes = AnnotationAttributes
					.fromMap(metadata.getAnnotationAttributes(AutoConfigurationPackage.class.getName(), false));
			List<String> packageNames = new ArrayList<>(Arrays.asList(attributes.getStringArray("basePackages")));
			for (Class<?> basePackageClass : attributes.getClassArray("basePackageClasses")) {
				packageNames.add(basePackageClass.getPackage().getName());
			}
			if (packageNames.isEmpty()) {
				packageNames.add(ClassUtils.getPackageName(metadata.getClassName()));
			}
			this.packageNames = Collections.unmodifiableList(packageNames);
		}

		List<String> getPackageNames() {
			return this.packageNames;
		}

		@Override
		public boolean equals(Object obj) {
			if (obj == null || getClass() != obj.getClass()) {
				return false;
			}
			return this.packageNames.equals(((PackageImports) obj).packageNames);
		}

		@Override
		public int hashCode() {
			return this.packageNames.hashCode();
		}

		@Override
		public String toString() {
			return "Package Imports " + this.packageNames;
		}

	}

	/**
	 * Holder for the base package (name may be null to indicate no scanning).
	 */
	static final class BasePackages {

		private final List<String> packages;

		private boolean loggedBasePackageInfo;

		BasePackages(String... names) {
			List<String> packages = new ArrayList<>();
			for (String name : names) {
				if (StringUtils.hasText(name)) {
					packages.add(name);
				}
			}
			this.packages = packages;
		}

		List<String> get() {
			if (!this.loggedBasePackageInfo) {
				if (this.packages.isEmpty()) {
					if (logger.isWarnEnabled()) {
						logger.warn("@EnableAutoConfiguration was declared on a class "
								+ "in the default package. Automatic @Repository and "
								+ "@Entity scanning is not enabled.");
					}
				}
				else {
					if (logger.isDebugEnabled()) {
						String packageNames = StringUtils.collectionToCommaDelimitedString(this.packages);
						logger.debug("@EnableAutoConfiguration was declared on a class in the package '" + packageNames
								+ "'. Automatic @Repository and @Entity scanning is enabled.");
					}
				}
				this.loggedBasePackageInfo = true;
			}
			return this.packages;
		}

	}

}

相关信息

spring 源码目录

相关文章

spring AbstractDependsOnBeanFactoryPostProcessor 源码

spring AutoConfiguration 源码

spring AutoConfigurationExcludeFilter 源码

spring AutoConfigurationImportEvent 源码

spring AutoConfigurationImportFilter 源码

spring AutoConfigurationImportListener 源码

spring AutoConfigurationImportSelector 源码

spring AutoConfigurationMetadata 源码

spring AutoConfigurationMetadataLoader 源码

spring AutoConfigurationPackage 源码

0  赞