1. xml-apis 冲突问题
javax.xml.parsers.FactoryConfigurationError: Provider for class javax.xml.parsers.DocumentBuilderFactory cannot be created
flink如果要操作hdfs,需要一个hadoop-hdfs的包.
如果项目里面有用dom4j相关包,就会与之有冲突,出现如下错误.
06/05/2018 11:40:40 Job execution switched to status FAILING.
javax.xml.parsers.FactoryConfigurationError: Provider for class javax.xml.parsers.DocumentBuilderFactory cannot be created
at javax.xml.parsers.FactoryFinder.findServiceProvider(FactoryFinder.java:311)
at javax.xml.parsers.FactoryFinder.find(FactoryFinder.java:267)
at javax.xml.parsers.DocumentBuilderFactory.newInstance(DocumentBuilderFactory.java:120)
at org.apache.hadoop.conf.Configuration.loadResource(Configuration.java:2516)
at org.apache.hadoop.conf.Configuration.loadResources(Configuration.java:2492)
at org.apache.hadoop.conf.Configuration.getProps(Configuration.java:2405)
at org.apache.hadoop.conf.Configuration.get(Configuration.java:981)
at org.apache.hadoop.conf.Configuration.getTrimmed(Configuration.java:1031)
at org.apache.hadoop.conf.Configuration.getClass(Configuration.java:2189)
at org.apache.hadoop.fs.FileSystem.getFileSystemClass(FileSystem.java:2654)
at org.apache.flink.runtime.fs.hdfs.HadoopFsFactory.create(HadoopFsFactory.java:99)
at org.apache.flink.core.fs.FileSystem.getUnguardedFileSystem(FileSystem.java:401)
at org.apache.flink.core.fs.FileSystem.get(FileSystem.java:320)
at org.apache.flink.core.fs.Path.getFileSystem(Path.java:293)
at org.apache.flink.runtime.state.filesystem.FsCheckpointStreamFactory.<init>(FsCheckpointStreamFactory.java:99)
at org.apache.flink.runtime.state.filesystem.FsStateBackend.createStreamFactory(FsStateBackend.java:277)
at org.apache.flink.streaming.runtime.tasks.StreamTask.createCheckpointStreamFactory(StreamTask.java:787)
at org.apache.flink.streaming.api.operators.AbstractStreamOperator.initializeState(AbstractStreamOperator.java:246)
at org.apache.flink.streaming.runtime.tasks.StreamTask.initializeOperators(StreamTask.java:694)
at org.apache.flink.streaming.runtime.tasks.StreamTask.initializeState(StreamTask.java:682)
at org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:253)
at org.apache.flink.runtime.taskmanager.Task.run(Task.java:718)
at java.lang.Thread.run(Thread.java:745)解决方案如下:
原因就是xml-apis包与dom4j冲突了.
把所有引的包的xml-apis依赖全部排除了
(顺便吐槽一下网上,有的说加这个包,有的说加哪个包,最后应该是全部排除xml-apis的依赖才对)
这里只是个样例,可以使用mvn tree看看依赖,全部排除干净才行
<dependency>
<groupId>org.apache.hadoop</groupId>
<artifactId>hadoop-hdfs</artifactId>
version>2.7.1</version>
<exclusions>
<exclusion>
<groupId>xml-apis</groupId>
<artifactId>xml-apis</artifactId>
</exclusion>
</exclusions>
</dependency>2. checkpoint 路径问题
Could not flush and close the file system output stream *** in order to obtain the stream state handle
如果flink集群在配置中,配置了默认checkpoint地址.
那么flink程序在设置checkpoint的时候,要与集群配置的地址一致.
错误现象如下:
java.lang.Exception: Could not perform checkpoint 1 for operator abcSink1 -> Sink: abcSink2 (4/5).
at org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpointOnBarrier(StreamTask.java:569)
at org.apache.flink.streaming.runtime.io.BarrierBuffer.notifyCheckpoint(BarrierBuffer.java:380)
at org.apache.flink.streaming.runtime.io.BarrierBuffer.processBarrier(BarrierBuffer.java:283)
at org.apache.flink.streaming.runtime.io.BarrierBuffer.getNextNonBlocked(BarrierBuffer.java:185)
at org.apache.flink.streaming.runtime.io.StreamInputProcessor.processInput(StreamInputProcessor.java:214)
at org.apache.flink.streaming.runtime.tasks.OneInputStreamTask.run(OneInputStreamTask.java:69)
at org.apache.flink.streaming.runtime.tasks.StreamTask.invoke(StreamTask.java:264)
at org.apache.flink.runtime.taskmanager.Task.run(Task.java:718)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.Exception: Could not complete snapshot 1 for operator abcSink1 -> Sink: abcSink2 (4/5).
at org.apache.flink.streaming.api.operators.AbstractStreamOperator.snapshotState(AbstractStreamOperator.java:378)
at org.apache.flink.streaming.runtime.tasks.StreamTask$CheckpointingOperation.checkpointStreamOperator(StreamTask.java:1089)
at org.apache.flink.streaming.runtime.tasks.StreamTask$CheckpointingOperation.executeCheckpointing(StreamTask.java:1038)
at org.apache.flink.streaming.runtime.tasks.StreamTask.checkpointState(StreamTask.java:671)
at org.apache.flink.streaming.runtime.tasks.StreamTask.performCheckpoint(StreamTask.java:607)
at org.apache.flink.streaming.runtime.tasks.StreamTask.triggerCheckpointOnBarrier(StreamTask.java:560)
... 8 more
Caused by: java.io.IOException: Could not flush and close the file system output stream to hdfs://localhost:8020/data/flink/checkpoint/2c418a966ed84cb035bb0574cb7c8d13/chk-1/989695d0-f3d8-40a0-addf-e4d2cc367794 in order to obtain the stream state handle
at org.apache.flink.runtime.state.filesystem.FsCheckpointStreamFactory$FsCheckpointStateOutputStream.closeAndGetHandle(FsCheckpointStreamFactory.java:336)
at org.apache.flink.runtime.state.KeyedStateCheckpointOutputStream.closeAndGetHandle(KeyedStateCheckpointOutputStream.java:105)
at org.apache.flink.runtime.state.KeyedStateCheckpointOutputStream.closeAndGetHandle(KeyedStateCheckpointOutputStream.java:30)
at org.apache.flink.runtime.state.StateSnapshotContextSynchronousImpl.closeAndUnregisterStreamToObtainStateHandle(StateSnapshotContextSynchronousImpl.java:126)
at org.apache.flink.runtime.state.StateSnapshotContextSynchronousImpl.getKeyedStateStreamFuture(StateSnapshotContextSynchronousImpl.java:113)
at org.apache.flink.streaming.api.operators.AbstractStreamOperator.snapshotState(AbstractStreamOperator.java:358)
... 13 more
Caused by: java.io.IOException: DataStreamer Exception:
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.run(DFSOutputStream.java:562)
Caused by: java.lang.NoClassDefFoundError: Could not initialize class org.apache.hadoop.hdfs.protocol.HdfsConstants
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.createBlockOutputStream(DFSOutputStream.java:1318)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.nextBlockOutputStream(DFSOutputStream.java:1262)
at org.apache.hadoop.hdfs.DFSOutputStream$DataStreamer.run(DFSOutputStream.java:448)
解决方案如下:
flink checkpoint 集群配置地址与 job的地址不一致,导致的问题
配置文件中的地址 state.backend.fs.checkpointdir: 地址
代码中的地址 env.setStateBackend(new FsStateBackend(地址))
这两个地方地址要一致