src/main/java/org/takes/tk/TkRetry.java
/*
* The MIT License (MIT)
*
* Copyright (c) 2014-2024 Yegor Bugayenko
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included
* in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package org.takes.tk;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.TimeUnit;
import org.cactoos.iterable.Mapped;
import org.cactoos.list.ListOf;
import org.takes.Request;
import org.takes.Response;
import org.takes.Take;
/**
* Decorator TkRetry, which will not fail immediately on Exception, but
* will retry a few times.
*
* @since 0.28.3
*/
public final class TkRetry implements Take {
/**
* Maximum number of retry attempts.
*/
private final int count;
/**
* Amount of time between retries, in milliseconds.
*/
private final int delay;
/**
* Original Take.
*/
private final Take take;
/**
* Constructor.
*
* @param retries Number of retry attempts
* @param wait Time between retries
* @param original Original take
*/
public TkRetry(final int retries, final int wait, final Take original) {
this.count = retries;
this.delay = wait;
this.take = original;
}
@Override
@SuppressWarnings("PMD.AvoidCatchingGenericException")
public Response act(final Request req) throws IOException {
if (this.count <= 0) {
throw new IllegalArgumentException(
"Can't make less than one attempt"
);
}
int attempts = 0;
final List<Exception> failures = new ArrayList<>(this.count);
while (attempts < this.count) {
try {
return this.take.act(req);
//@checkstyle IllegalCatch (1 line)
} catch (final Exception ex) {
++attempts;
failures.add(ex);
this.sleep();
}
}
throw new IOException(
String.format(
"failed after %d attempts: %s",
failures.size(),
new ListOf<>(
new Mapped<>(
Exception::getMessage,
failures
)
)
),
failures.get(failures.size() - 1)
);
}
/**
* Sleep.
*/
private void sleep() {
try {
TimeUnit.MILLISECONDS.sleep(this.delay);
} catch (final InterruptedException ex) {
Thread.currentThread().interrupt();
throw new IllegalStateException(
"Unexpected interruption while retrying to process request",
ex
);
}
}
}