Java tutorial
/* * Copyright 2002-2018 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 * * 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 org.springframework.core.io.buffer; import java.nio.charset.StandardCharsets; import java.util.Arrays; import java.util.List; import java.util.function.Consumer; import io.netty.buffer.ByteBufAllocator; import io.netty.buffer.PoolArenaMetric; import io.netty.buffer.PooledByteBufAllocator; import io.netty.buffer.PooledByteBufAllocatorMetric; import io.netty.buffer.UnpooledByteBufAllocator; import org.junit.Rule; import org.junit.rules.Verifier; import org.junit.runner.RunWith; import org.junit.runners.Parameterized; import reactor.core.publisher.Mono; import org.springframework.core.io.buffer.support.DataBufferTestUtils; import static org.junit.Assert.*; /** * @author Arjen Poutsma */ @RunWith(Parameterized.class) public abstract class AbstractDataBufferAllocatingTestCase { @Parameterized.Parameter public DataBufferFactory bufferFactory; @Parameterized.Parameters(name = "{0}") public static Object[][] dataBufferFactories() { return new Object[][] { { new NettyDataBufferFactory(new UnpooledByteBufAllocator(true)) }, { new NettyDataBufferFactory(new UnpooledByteBufAllocator(false)) }, // disable caching for reliable leak detection, see https://github.com/netty/netty/issues/5275 { new NettyDataBufferFactory(new PooledByteBufAllocator(true, 1, 1, 8192, 11, 0, 0, 0, true)) }, { new NettyDataBufferFactory(new PooledByteBufAllocator(false, 1, 1, 8192, 11, 0, 0, 0, true)) }, { new DefaultDataBufferFactory(true) }, { new DefaultDataBufferFactory(false) } }; } @Rule public final Verifier leakDetector = new LeakDetector(); protected DataBuffer createDataBuffer(int capacity) { return this.bufferFactory.allocateBuffer(capacity); } protected DataBuffer stringBuffer(String value) { return byteBuffer(value.getBytes(StandardCharsets.UTF_8)); } protected Mono<DataBuffer> deferStringBuffer(String value) { return Mono.defer(() -> Mono.just(stringBuffer(value))); } protected DataBuffer byteBuffer(byte[] value) { DataBuffer buffer = this.bufferFactory.allocateBuffer(value.length); buffer.write(value); return buffer; } protected void release(DataBuffer... buffers) { Arrays.stream(buffers).forEach(DataBufferUtils::release); } protected Consumer<DataBuffer> stringConsumer(String expected) { return dataBuffer -> { String value = DataBufferTestUtils.dumpString(dataBuffer, StandardCharsets.UTF_8); DataBufferUtils.release(dataBuffer); assertEquals(expected, value); }; } private class LeakDetector extends Verifier { @Override protected void verify() throws Throwable { if (bufferFactory instanceof NettyDataBufferFactory) { ByteBufAllocator byteBufAllocator = ((NettyDataBufferFactory) bufferFactory).getByteBufAllocator(); if (byteBufAllocator instanceof PooledByteBufAllocator) { PooledByteBufAllocator pooledByteBufAllocator = (PooledByteBufAllocator) byteBufAllocator; PooledByteBufAllocatorMetric metric = pooledByteBufAllocator.metric(); long allocations = calculateAllocations(metric.directArenas()) + calculateAllocations(metric.heapArenas()); assertTrue("ByteBuf leak detected: " + allocations + " allocations were not released", allocations == 0); } } } private long calculateAllocations(List<PoolArenaMetric> metrics) { return metrics.stream().mapToLong(PoolArenaMetric::numActiveAllocations).sum(); } } }