/*
* Copyright 2015 Ben Manes. All Rights Reserved.
*
* 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
*
* 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 com.github.benmanes.caffeine.cache;
import static java.util.Objects.requireNonNull;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.is;
import static org.hamcrest.Matchers.lessThanOrEqualTo;
import static org.hamcrest.Matchers.nullValue;
import java.util.function.Consumer;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;
import com.github.benmanes.caffeine.testing.ConcurrentTestHarness;
import com.google.common.base.MoreObjects;
/**
* @author ben.manes@gmail.com (Ben Manes)
*/
public final class StripedBufferTest {
static final Integer ELEMENT = 1;
@Test(dataProvider = "buffers")
public void init(FakeBuffer<Integer> buffer) {
assertThat(buffer.table, is(nullValue()));
buffer.offer(ELEMENT);
assertThat(buffer.table.length, is(1));
}
@Test(dataProvider = "buffers")
public void produce(FakeBuffer<Integer> buffer) {
ConcurrentTestHarness.timeTasks(10, () -> {
for (int i = 0; i < 10; i++) {
buffer.offer(ELEMENT);
Thread.yield();
}
});
assertThat(buffer.table.length, lessThanOrEqualTo(StripedBuffer.MAXIMUM_TABLE_SIZE));
}
@Test(dataProvider = "buffers")
public void drain(FakeBuffer<Integer> buffer) {
buffer.drainTo(e -> {});
assertThat(buffer.drains, is(0));
// Expand and drain
buffer.offer(ELEMENT);
buffer.drainTo(e -> {});
assertThat(buffer.drains, is(1));
}
@DataProvider
public Object[][] buffers() {
return new Object[][] {
{ new FakeBuffer<Integer>(Buffer.FULL) },
{ new FakeBuffer<Integer>(Buffer.FAILED) },
{ new FakeBuffer<Integer>(Buffer.SUCCESS) },
};
}
static int ceilingNextPowerOfTwo(int x) {
return 1 << (Integer.SIZE - Integer.numberOfLeadingZeros(x - 1));
}
static final class FakeBuffer<E> extends StripedBuffer<E> {
final int result;
int drains = 0;
FakeBuffer(int result) {
this.result = requireNonNull(result);
}
@Override protected Buffer<E> create(E e) {
return new Buffer<E>() {
@Override public int offer(E e) {
return result;
}
@Override public void drainTo(Consumer<E> consumer) {
drains++;
}
@Override public int size() {
return 0;
}
@Override public int reads() {
return 0;
}
@Override public int writes() {
return 0;
}
};
}
@Override
public String toString() {
return MoreObjects.toStringHelper(this).addValue(result).toString();
}
}
}