/*
 * Copyright 2012-2019 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.web.servlet;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

import javax.servlet.annotation.WebFilter;
import javax.servlet.annotation.WebListener;
import javax.servlet.annotation.WebServlet;

import org.springframework.context.annotation.Import;
import org.springframework.core.annotation.AliasFor;

Enables scanning for Servlet components (filters, 
servlets, and listeners). Scanning is only performed when using an embedded web server. 
 Typically, one of value, basePackages, or basePackageClasses should be specified to control the packages to be scanned for components. In their absence, scanning will be performed from the package of the class with the annotation. 
Author:
Andy Wilkinson
See Also:
WebServlet
WebFilter
WebListener
Since:
1.3.0/**
 * Enables scanning for Servlet components ({@link WebFilter filters}, {@link WebServlet
 * servlets}, and {@link WebListener listeners}). Scanning is only performed when using an
 * embedded web server.
 * <p>
 * Typically, one of {@code value}, {@code basePackages}, or {@code basePackageClasses}
 * should be specified to control the packages to be scanned for components. In their
 * absence, scanning will be performed from the package of the class with the annotation.
 *
 * @author Andy Wilkinson
 * @since 1.3.0
 * @see WebServlet
 * @see WebFilter
 * @see WebListener
 */
@Target(ElementType.TYPE)
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Import(ServletComponentScanRegistrar.class)
public @interface ServletComponentScan {

	
Alias for the basePackages() attribute. Allows for more concise annotation declarations e.g.: @ServletComponentScan("org.my.pkg") instead of @ServletComponentScan(basePackages="org.my.pkg"). 
Returns:
the base packages to scan/**
	 * Alias for the {@link #basePackages()} attribute. Allows for more concise annotation
	 * declarations e.g.: {@code @ServletComponentScan("org.my.pkg")} instead of
	 * {@code @ServletComponentScan(basePackages="org.my.pkg")}.
	 * @return the base packages to scan
	 */
	@AliasFor("basePackages")
	String[] value() default {};

	
Base packages to scan for annotated servlet components. value() is an alias for (and mutually exclusive with) this attribute. 
 Use basePackageClasses() for a type-safe alternative to String-based package names. 
Returns:
the base packages to scan/**
	 * Base packages to scan for annotated servlet components. {@link #value()} is an
	 * alias for (and mutually exclusive with) this attribute.
	 * <p>
	 * Use {@link #basePackageClasses()} for a type-safe alternative to String-based
	 * package names.
	 * @return the base packages to scan
	 */
	@AliasFor("value")
	String[] basePackages() default {};

	
Type-safe alternative to basePackages() for specifying the packages to scan for annotated servlet components. The package of each class specified will be scanned. 
Returns:
classes from the base packages to scan/**
	 * Type-safe alternative to {@link #basePackages()} for specifying the packages to
	 * scan for annotated servlet components. The package of each class specified will be
	 * scanned.
	 * @return classes from the base packages to scan
	 */
	Class<?>[] basePackageClasses() default {};

}