| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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.apache.beam.sdk.util; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.LinkedList; |
| import java.util.List; |
| import java.util.Set; |
| import java.util.concurrent.atomic.AtomicInteger; |
| import org.apache.beam.sdk.coders.AtomicCoder; |
| import org.apache.beam.sdk.coders.ByteArrayCoder; |
| import org.apache.beam.sdk.coders.Coder; |
| import org.apache.beam.sdk.coders.CoderException; |
| import org.apache.beam.sdk.coders.IterableCoder; |
| import org.apache.beam.sdk.coders.ListCoder; |
| import org.apache.beam.sdk.coders.VarIntCoder; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.collect.FluentIterable; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.collect.Lists; |
| import org.apache.beam.vendor.guava.v20_0.com.google.common.collect.Sets; |
| import org.junit.Rule; |
| import org.junit.Test; |
| import org.junit.rules.ExpectedException; |
| import org.junit.runner.RunWith; |
| import org.junit.runners.JUnit4; |
| |
| /** Tests for {@link MutationDetectors}. */ |
| @RunWith(JUnit4.class) |
| public class MutationDetectorsTest { |
| /** |
| * Solely used to test that immutability is enforced from the SDK's perspective and not from |
| * Java's {@link Object#equals} method. Note that we do not expect users to create such an |
| * implementation. |
| */ |
| private static class ForSDKMutationDetectionTestCoder extends AtomicCoder<Object> { |
| // Use a unique instance that is returned as the structural value making all structural |
| // values of this coder equivalent to each other. |
| private final Object uniqueInstance = new Object(); |
| |
| @Override |
| public void encode(Object value, OutputStream outStream) throws IOException {} |
| |
| @Override |
| public Object decode(InputStream inStream) throws IOException { |
| return new AtomicInteger(); |
| } |
| |
| @Override |
| public Object structuralValue(Object value) { |
| return uniqueInstance; |
| } |
| } |
| |
| @Rule public ExpectedException thrown = ExpectedException.none(); |
| |
| /** |
| * Tests that mutation detection is enforced from the SDK point of view (Based on the {@link |
| * Coder#structuralValue}) and not from the Java's equals method. |
| */ |
| @Test |
| public void testMutationBasedOnStructuralValue() throws Exception { |
| AtomicInteger value = new AtomicInteger(); |
| MutationDetector detector = |
| MutationDetectors.forValueWithCoder(value, new ForSDKMutationDetectionTestCoder()); |
| // Even though we modified the value, we are relying on the fact that the structural |
| // value will be used to compare equality |
| value.incrementAndGet(); |
| detector.verifyUnmodified(); |
| } |
| |
| @Test |
| public void testMutationWithEqualEncodings() throws Exception { |
| class EncodingBadStructuralValueCoder extends AtomicCoder<List<Object>> { |
| @Override |
| public void encode(List<Object> value, OutputStream outStream) |
| throws CoderException, IOException { |
| outStream.write(new byte[] {1, 2, -3, 45}); |
| } |
| |
| @Override |
| public List<Object> decode(InputStream inStream) throws CoderException, IOException { |
| // Consume the written bytes |
| int read = inStream.read(new byte[4]); |
| return new ArrayList<>(); |
| } |
| |
| @Override |
| public Object structuralValue(List<Object> value) { |
| // Structural values are never equal to each other. |
| return new Object(); |
| } |
| } |
| |
| List<Object> ls = new ArrayList<>(); |
| ls.add(1); |
| ls.add("foo"); |
| |
| MutationDetector detector = |
| MutationDetectors.forValueWithCoder(ls, new EncodingBadStructuralValueCoder()); |
| ls.add(new Byte[] {1, 2, -3, 45}); |
| |
| // The structural values should be unequal, but the encoded bytes are equivalent, which is the |
| // system definition of equality. |
| detector.verifyUnmodified(); |
| } |
| |
| /** Tests that {@link MutationDetectors#forValueWithCoder} detects a mutation to a list. */ |
| @Test |
| public void testMutatingList() throws Exception { |
| List<Integer> value = Arrays.asList(1, 2, 3, 4); |
| MutationDetector detector = |
| MutationDetectors.forValueWithCoder(value, ListCoder.of(VarIntCoder.of())); |
| value.set(0, 37); |
| |
| thrown.expect(IllegalMutationException.class); |
| detector.verifyUnmodified(); |
| } |
| |
| /** |
| * Tests that {@link MutationDetectors#forValueWithCoder} does not false positive on a {@link |
| * LinkedList} that will clone as an {@code ArrayList}. |
| */ |
| @Test |
| public void testUnmodifiedLinkedList() throws Exception { |
| List<Integer> value = Lists.newLinkedList(Arrays.asList(1, 2, 3, 4)); |
| MutationDetector detector = |
| MutationDetectors.forValueWithCoder(value, ListCoder.of(VarIntCoder.of())); |
| detector.verifyUnmodified(); |
| } |
| |
| /** |
| * Tests that {@link MutationDetectors#forValueWithCoder} does not false positive on a {@link |
| * LinkedList} coded as an {@link Iterable}. |
| */ |
| @Test |
| public void testImmutableList() throws Exception { |
| List<Integer> value = Lists.newLinkedList(Arrays.asList(1, 2, 3, 4)); |
| MutationDetector detector = |
| MutationDetectors.forValueWithCoder(value, IterableCoder.of(VarIntCoder.of())); |
| detector.verifyUnmodified(); |
| } |
| |
| /** |
| * Tests that {@link MutationDetectors#forValueWithCoder} does not false positive on a {@link Set} |
| * coded as an {@link Iterable}. |
| */ |
| @Test |
| public void testImmutableSet() throws Exception { |
| Set<Integer> value = Sets.newHashSet(Arrays.asList(1, 2, 3, 4)); |
| MutationDetector detector = |
| MutationDetectors.forValueWithCoder(value, IterableCoder.of(VarIntCoder.of())); |
| detector.verifyUnmodified(); |
| } |
| |
| /** |
| * Tests that {@link MutationDetectors#forValueWithCoder} does not false positive on a {@link Set} |
| * coded as an {@link Iterable}. |
| */ |
| @Test |
| public void testStructuralValue() throws Exception { |
| Set<Integer> value = Sets.newHashSet(Arrays.asList(1, 2, 3, 4)); |
| MutationDetector detector = |
| MutationDetectors.forValueWithCoder(value, IterableCoder.of(VarIntCoder.of())); |
| detector.verifyUnmodified(); |
| } |
| |
| /** |
| * Tests that {@link MutationDetectors#forValueWithCoder} does not false positive on an {@link |
| * Iterable} that is not known to be bounded; after coder-based cloning the bound will be known |
| * and it will be a {@link List} so it will encode more compactly the second time around. |
| */ |
| @Test |
| public void testImmutableIterable() throws Exception { |
| Iterable<Integer> value = FluentIterable.from(Arrays.asList(1, 2, 3, 4)).cycle().limit(50); |
| MutationDetector detector = |
| MutationDetectors.forValueWithCoder(value, IterableCoder.of(VarIntCoder.of())); |
| detector.verifyUnmodified(); |
| } |
| |
| /** Tests that {@link MutationDetectors#forValueWithCoder} detects a mutation to a byte array. */ |
| @Test |
| public void testMutatingArray() throws Exception { |
| byte[] value = new byte[] {0x1, 0x2, 0x3, 0x4}; |
| MutationDetector detector = MutationDetectors.forValueWithCoder(value, ByteArrayCoder.of()); |
| value[0] = 0xa; |
| thrown.expect(IllegalMutationException.class); |
| detector.verifyUnmodified(); |
| } |
| |
| /** |
| * Tests that {@link MutationDetectors#forValueWithCoder} does not false positive on an array, |
| * even though it will decode is another array which Java will not say is {@code equals}. |
| */ |
| @Test |
| public void testUnmodifiedArray() throws Exception { |
| byte[] value = new byte[] {0x1, 0x2, 0x3, 0x4}; |
| MutationDetector detector = MutationDetectors.forValueWithCoder(value, ByteArrayCoder.of()); |
| detector.verifyUnmodified(); |
| } |
| |
| /** |
| * Tests that {@link MutationDetectors#forValueWithCoder} does not false positive on an list of |
| * arrays, even when some array is set to a deeply equal array that is not {@code equals}. |
| */ |
| @Test |
| public void testEquivalentListOfArrays() throws Exception { |
| List<byte[]> value = Arrays.asList(new byte[] {0x1}, new byte[] {0x2, 0x3}, new byte[] {0x4}); |
| MutationDetector detector = |
| MutationDetectors.forValueWithCoder(value, ListCoder.of(ByteArrayCoder.of())); |
| value.set(0, new byte[] {0x1}); |
| detector.verifyUnmodified(); |
| } |
| } |