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/**
* Copyright (c) 2012-2014, jcabi.com
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met: 1) Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer. 2) Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials provided
* with the distribution. 3) Neither the name of the jcabi.com nor
* the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior written
* permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
* NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
* THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
* OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.jcabi.aspects;
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 java.util.concurrent.TimeUnit;
/**
* Makes a method response cacheable in memory for some time.
*
* For example, this {@code load()} method loads some data from the network
* and we want it to cache loaded data for 5 seconds (to avoid delays):
*
*
@Cacheable(lifetime = 5, unit = TimeUnit.SECONDS)
* String load(String resource) throws IOException {
* return "something";
* }
*
* You can cache them forever, which means that once calculated and
* cached value will never expire (may be a nice alternative to static
* initializers):
*
*
@Cacheable(forever = true)
* String load(String resource) throws IOException {
* return "something";
* }
*
* Since version 0.7.14 you can also annotate methods that should flush
* cache of the object, for example:
*
*
public class Page {
* @Cacheable
* public String get() {
* // load data from external source, e.g. the network
* return data;
* }
* @Cacheable.Flush
* public void set(String data) {
* // save data to the network
* }
* }
*
* Since 0.7.18 you can control when exactly flushing happens, with
* {@link Cacheable.FlushBefore} and {@link Cacheable.FlushAfter} annotations
* ({@link Cacheable.Flush} is deprecated).
*
* @author Yegor Bugayenko ([email protected])
* @version $Id$
* @since 0.7.7
* @see http://www.jcabi.com/jcabi-aspects/
*/
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface Cacheable {
/**
* Lifetime of an object in cache, in time units.
*/
int lifetime() default 1;
/**
* Time units of object lifetime.
*
*
The minimum unit you can use is a second. We simply can't cache for
* less than a second, because cache is being cleaned every second.
*/
TimeUnit unit() default TimeUnit.MINUTES;
/**
* Keep in cache forever.
*/
boolean forever() default false;
/**
* Identifies a method that should flush all cached entities of
* this class/object.
* @since 0.7.14
* @deprecated It is identical to {@link FlushBefore}
*/
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
@Deprecated
public @interface Flush {
}
/**
* Identifies a method that should flush all cached entities of
* this class/object, before being executed.
* @since 0.7.18
*/
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface FlushBefore {
}
/**
* Identifies a method that should flush all cached entities of
* this class/object, after being executed.
* @since 0.7.18
*/
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.METHOD)
public @interface FlushAfter {
}
}