以下代码是引发异常的地方：
PCollection<String> pCol = pBegin
.apply(String.format("Read from %s", this.subscriptionId),
PubsubIO.readStrings().fromSubscription(this.subscriptionId));
这是抛出的异常：
Caused by: java.lang.NoSuchMethodError: com.google.common.base.Preconditions.checkState(ZLjava/lang/String;Ljava/lang/Object;)V
at org.apache.beam.sdk.io.gcp.pubsub.PubsubClient$SubscriptionPath.<init>(PubsubClient.java:188)
at org.apache.beam.sdk.io.gcp.pubsub.PubsubClient.subscriptionPathFromName(PubsubClient.java:238)
at org.apache.beam.sdk.io.gcp.pubsub.PubsubIO$SubscriptionPathTranslator.apply(PubsubIO.java:289)
at org.apache.beam.sdk.io.gcp.pubsub.PubsubIO$SubscriptionPathTranslator.apply(PubsubIO.java:284)
at org.apache.beam.sdk.options.ValueProvider$NestedValueProvider.get(ValueProvider.java:131)
at org.apache.beam.sdk.io.gcp.pubsub.PubsubUnboundedSource.getSubscription(PubsubUnboundedSource.java:1374)
at org.apache.beam.sdk.io.gcp.pubsub.PubsubUnboundedSource$PubsubSource.<init>(PubsubUnboundedSource.java:1103)
at org.apache.beam.sdk.io.gcp.pubsub.PubsubUnboundedSource.expand(PubsubUnboundedSource.java:1407)
at org.apache.beam.sdk.io.gcp.pubsub.PubsubUnboundedSource.expand(PubsubUnboundedSource.java:110)
at org.apache.beam.sdk.Pipeline.applyInternal(Pipeline.java:482)
at org.apache.beam.sdk.Pipeline.applyTransform(Pipeline.java:422)
at org.apache.beam.sdk.values.PBegin.apply(PBegin.java:44)
at org.apache.beam.sdk.io.gcp.pubsub.PubsubIO$Read.expand(PubsubIO.java:730)
at org.apache.beam.sdk.io.gcp.pubsub.PubsubIO$Read.expand(PubsubIO.java:536)
at org.apache.beam.sdk.Pipeline.applyInternal(Pipeline.java:482)
at org.apache.beam.sdk.Pipeline.applyTransform(Pipeline.java:441)
at org.apache.beam.sdk.values.PBegin.apply(PBegin.java:56)
at com.arquivei.internal.pipelines.NfeViewPipeline.buildPipeline(NfeViewPipeline.java:128)
at com.arquivei.internal.common.base.PubSubPipeline.buildPipeline(PubSubPipeline.java:33)
at com.arquivei.internal.ExecutePipeline$1.expand(ExecutePipeline.java:30)
at com.arquivei.internal.ExecutePipeline$1.expand(ExecutePipeline.java:26)
at org.apache.beam.sdk.Pipeline.applyInternal(Pipeline.java:482)
at org.apache.beam.sdk.Pipeline.applyTransform(Pipeline.java:441)
at org.apache.beam.sdk.values.PBegin.apply(PBegin.java:56)
at org.apache.beam.sdk.Pipeline.apply(Pipeline.java:179)
at com.arquivei.internal.ExecutePipeline.addPipelineAsSubTask(ExecutePipeline.java:26)
at com.arquivei.internal.ExecutePipeline.main(ExecutePipeline.java:118)
... 6 more
我已经仔细检查了this.subscriptionId并且它不是空的并且遵循模式projects / project_id / subscriptions / subscription_name
如何解决此问题？任何具有使用Beam 2.0.0从Pubsub订阅读取的代码示例的资源也将受到赞赏。
项目的pom.xml：
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<packaging>jar</packaging>
<properties>
<beam.version>2.0.0</beam.version>
<google.cloud.version>0.18.0-alpha</google.cloud.version>
<dataflow.version>2.0.0-beta2</dataflow.version>
</properties>
<repositories>
<repository>
<id>apache.snapshots</id>
<name>Apache Development Snapshot Repository</name>
<url>https://repository.apache.org/content/repositories/snapshots/</url>
<releases>
<enabled>false</enabled>
</releases>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
</repositories>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.5.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-surefire-plugin</artifactId>
<version>2.19.1</version>
<configuration>
<parallel>all</parallel>
<threadCount>4</threadCount>
<redirectTestOutputToFile>true</redirectTestOutputToFile>
</configuration>
<dependencies>
<dependency>
<groupId>org.apache.maven.surefire</groupId>
<artifactId>surefire-junit47</artifactId>
<version>2.19.1</version>
</dependency>
</dependencies>
</plugin>
</plugins>
<pluginManagement>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.4.0</version>
<configuration>
<cleanupDaemonThreads>false</cleanupDaemonThreads>
</configuration>
</plugin>
<!--
Configures `mvn package` to produce a bundled jar ("fat jar") for runners
that require this for job submission to a cluster.
-->
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.4.1</version>
<executions>
<execution>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<finalName>${project.artifactId}-bundled-${project.version}</finalName>
<filters>
<filter>
<artifact>*:*</artifact>
<excludes>
<exclude>META-INF/LICENSE</exclude>
</excludes>
</filter>
</filters>
</configuration>
</execution>
</executions>
</plugin>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>properties-maven-plugin</artifactId>
<version>1.0-alpha-2</version>
<executions>
<execution>
<phase>initialize</phase>
<goals>
<goal>read-project-properties</goal>
</goals>
<configuration>
<files>
<file>config/project.properties</file>
</files>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</pluginManagement>
</build>
<dependencies>
<dependency>
<groupId>org.apache.beam</groupId>
<artifactId>beam-runners-google-cloud-dataflow-java</artifactId>
<version>${beam.version}</version>
</dependency>
<!-- Adds a dependency on the Beam SDK. -->
<dependency>
<groupId>org.apache.beam</groupId>
<artifactId>beam-sdks-java-core</artifactId>
<version>${beam.version}</version>
</dependency>
<!-- Adds a dependency on the Beam Google Cloud Platform IO module. -->
<dependency>
<groupId>org.apache.beam</groupId>
<artifactId>beam-sdks-java-io-google-cloud-platform</artifactId>
<version>${beam.version}</version>
</dependency>
<!-- The DirectRunner is needed for unit tests. -->
<dependency>
<groupId>org.apache.beam</groupId>
<artifactId>beam-runners-direct-java</artifactId>
<version>${beam.version}</version>
</dependency>
<dependency>
<groupId>org.apache.beam</groupId>
<artifactId>beam-sdks-java-io-jdbc</artifactId>
<version>${beam.version}</version>
</dependency>
<dependency>
<groupId>org.apache.beam</groupId>
<artifactId>beam-runners-core-java</artifactId>
<version>${beam.version}</version>
</dependency>
<dependency>
<groupId>com.google.cloud</groupId>
<artifactId>google-cloud</artifactId>
<version>${google.cloud.version}</version>
</dependency>
<!-- Dependencies below this line are specific dependencies needed by the examples code. -->
<dependency>
<groupId>com.google.api-client</groupId>
<artifactId>google-api-client</artifactId>
<version>1.22.0</version>
<exclusions>
<!-- Exclude an old version of guava that is being pulled
in by a transitive dependency of google-api-client -->
<exclusion>
<groupId>com.google.guava</groupId>
<artifactId>guava-jdk5</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>com.google.apis</groupId>
<artifactId>google-api-services-bigquery</artifactId>
<version>v2-rev295-1.22.0</version>
<exclusions>
<!-- Exclude an old version of guava that is being pulled
in by a transitive dependency of google-api-client -->
<exclusion>
<groupId>com.google.guava</groupId>
<artifactId>guava-jdk5</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>com.google.http-client</groupId>
<artifactId>google-http-client</artifactId>
<version>1.22.0</version>
<exclusions>
<!-- Exclude an old version of guava that is being pulled
in by a transitive dependency of google-api-client -->
<exclusion>
<groupId>com.google.guava</groupId>
<artifactId>guava-jdk5</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>com.google.apis</groupId>
<artifactId>google-api-services-pubsub</artifactId>
<version>v1-rev10-1.22.0</version>
<exclusions>
<!-- Exclude an old version of guava that is being pulled
in by a transitive dependency of google-api-client -->
<exclusion>
<groupId>com.google.guava</groupId>
<artifactId>guava-jdk5</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>joda-time</groupId>
<artifactId>joda-time</artifactId>
<version>2.4</version>
</dependency>
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>19.0</version>
</dependency>
<!-- Add slf4j API frontend binding with JUL backend -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.14</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-jdk14</artifactId>
<version>1.7.14</version>
<!-- When loaded at runtime this will wire up slf4j to the JUL backend -->
</dependency>
<!-- Hamcrest and JUnit are required dependencies of PAssert,
which is used in the main code of DebuggingWordCount example. -->
<dependency>
<groupId>org.hamcrest</groupId>
<artifactId>hamcrest-all</artifactId>
<version>1.3</version>
</dependency>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
<dependency>
<groupId>org.postgresql</groupId>
<artifactId>postgresql</artifactId>
<version>42.0.0</version>
</dependency>
<dependency>
<groupId>org.ini4j</groupId>
<artifactId>ini4j</artifactId>
<version>0.5.4</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.dataformat</groupId>
<artifactId>jackson-dataformat-yaml</artifactId>
<version>2.8.6</version>
</dependency>
<dependency>
<groupId>org.reflections</groupId>
<artifactId>reflections</artifactId>
<version>0.9.10</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>4.0.0-b03</version>
</dependency>
<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version>20160810</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.3</version>
</dependency>
</dependencies>
解决方案：将Guava版本从19更改为20解决了这个问题。
<dependency>
<groupId>com.google.guava</groupId>
<artifactId>guava</artifactId>
<version>20.0</version>
</dependency>