io.microsphere.spring.config.context.annotation.AnnotatedPropertySourceLoader Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 io.microsphere.spring.config.context.annotation;
import io.microsphere.spring.context.annotation.BeanCapableImportCandidate;
import io.microsphere.spring.core.annotation.ResolvablePlaceholderAnnotationAttributes;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.BeanCreationException;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.ImportSelector;
import org.springframework.core.ResolvableType;
import org.springframework.core.annotation.AnnotationAttributes;
import org.springframework.core.env.MutablePropertySources;
import org.springframework.core.env.PropertySource;
import org.springframework.core.type.AnnotationMetadata;
import org.springframework.lang.NonNull;
import org.springframework.lang.Nullable;
import java.lang.annotation.Annotation;
import java.util.Map;
import static io.microsphere.util.StringUtils.EMPTY_STRING_ARRAY;
import static org.springframework.util.StringUtils.hasText;
/**
* Abstract {@link ImportSelector} class to load the {@link PropertySource PropertySource}
* when the {@link Configuration configuration} annotated the specified annotation
*
* @param The type of {@link Annotation}
* @author Mercy
* @see ResourcePropertySourceLoader
* @see PropertySourceExtensionLoader
* @see ImportSelector
* @since 1.0.0
*/
public abstract class AnnotatedPropertySourceLoader extends BeanCapableImportCandidate
implements ImportSelector {
private static final String[] NO_CLASS_TO_IMPORT = EMPTY_STRING_ARRAY;
protected static final String NAME_ATTRIBUTE_NAME = "name";
protected final Logger logger = LoggerFactory.getLogger(this.getClass());
private final Class annotationType;
private String propertySourceName;
public AnnotatedPropertySourceLoader() {
this.annotationType = resolveAnnotationType();
}
protected Class resolveAnnotationType() {
ResolvableType type = ResolvableType.forType(this.getClass());
ResolvableType superType = type.as(AnnotatedPropertySourceLoader.class);
return (Class) superType.resolveGeneric(0);
}
@Override
public final String[] selectImports(AnnotationMetadata metadata) {
String annotationClassName = annotationType.getName();
Map annotationAttributes = metadata.getAnnotationAttributes(annotationClassName);
ResolvablePlaceholderAnnotationAttributes attributes = ResolvablePlaceholderAnnotationAttributes.of(annotationAttributes, annotationType, getEnvironment());
String propertySourceName = resolvePropertySourceName(attributes, metadata);
this.propertySourceName = propertySourceName;
MutablePropertySources propertySources = getEnvironment().getPropertySources();
try {
loadPropertySource(attributes, metadata, propertySourceName, propertySources);
} catch (Throwable e) {
String errorMessage = "The Configuration bean[class : '" + metadata.getClassName() + "', annotated : @" + annotationClassName + "] can't load the PropertySource[name : '" + propertySourceName + "']";
logger.error(errorMessage, e);
throw new BeanCreationException(errorMessage, e);
}
return NO_CLASS_TO_IMPORT;
}
/**
* Resolve the name of {@link PropertySource}
*
* @param attributes {@link AnnotationAttributes}
* @param metadata {@link AnnotationMetadata}
* @return non-null
*/
@NonNull
protected final String resolvePropertySourceName(AnnotationAttributes attributes, AnnotationMetadata metadata) {
String name = buildPropertySourceName(attributes, metadata);
if (!hasText(name)) {
name = buildDefaultPropertySourceName(attributes, metadata);
}
return name;
}
/**
* Build the name of {@link PropertySource}
*
* @param attributes {@link AnnotationAttributes}
* @param metadata {@link AnnotationMetadata}
* @return the attribute value of annotation if the {@link #NAME_ATTRIBUTE_NAME "name"} attribute present, or null
*/
@Nullable
protected String buildPropertySourceName(AnnotationAttributes attributes, AnnotationMetadata metadata) {
if (attributes.containsKey(NAME_ATTRIBUTE_NAME)) {
return attributes.getString(NAME_ATTRIBUTE_NAME);
}
return null;
}
/**
* Build the default name of {@link PropertySource}
*
* @param attributes {@link AnnotationAttributes}
* @param metadata {@link AnnotationMetadata}
* @return non-null
*/
@NonNull
protected String buildDefaultPropertySourceName(AnnotationAttributes attributes, AnnotationMetadata metadata) {
String annotationClassName = annotationType.getName();
String introspectedClassName = metadata.getClassName();
return introspectedClassName + "@" + annotationClassName;
}
/**
* Load the {@link PropertySource}
*
* @param attributes {@link AnnotationAttributes}
* @param metadata {@link AnnotationMetadata}
* @param propertySourceName the name of {@link PropertySource}
* @param propertySources {@link MutablePropertySources} to be added
* @throws Throwable the failure of the loading
*/
@Nullable
protected abstract void loadPropertySource(AnnotationAttributes attributes, AnnotationMetadata metadata,
String propertySourceName, MutablePropertySources propertySources) throws Throwable;
/**
* The annotation type
*
* @return non-null
*/
@NonNull
public final Class getAnnotationType() {
return annotationType;
}
protected String getPropertySourceName() {
return this.propertySourceName;
}
}