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Ashish Singhi commented on HBASE-5878: -------------------------------------- [~apurtell], we cannot throw the exception as is, as the method is overridden from [FSDataInputStream|https://github.com/apache/hadoop/blob/trunk/hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FSDataInputStream.java] which throws IOE. I can wrap the exception in a new IOE and throw that, is this ok for all the fix versions ? Just want confirm it before I attach a new patch. > Use getVisibleLength public api from HdfsDataInputStream from Hadoop-2. > ----------------------------------------------------------------------- > > Key: HBASE-5878 > URL: https://issues.apache.org/jira/browse/HBASE-5878 > Project: HBase > Issue Type: Bug > Components: wal > Reporter: Uma Maheswara Rao G > Assignee: Ashish Singhi > Fix For: 2.0.0, 1.3.0 > > Attachments: HBASE-5878-v2.patch, HBASE-5878-v3.patch, > HBASE-5878-v4.patch, HBASE-5878-v5-0.98.patch, HBASE-5878-v5.patch, > HBASE-5878-v5.patch, HBASE-5878.patch > > > SequencFileLogReader: > Currently Hbase using getFileLength api from DFSInputStream class by > reflection. DFSInputStream is not exposed as public. So, this may change in > future. Now HDFS exposed HdfsDataInputStream as public API. > We can make use of it, when we are not able to find the getFileLength api > from DFSInputStream as a else condition. So, that we will not have any sudden > surprise like we are facing today. > Also, it is just logging one warn message and proceeding if it throws any > exception while getting the length. I think we can re-throw the exception > because there is no point in continuing with dataloss. > {code} > long adjust = 0; > try { > Field fIn = FilterInputStream.class.getDeclaredField("in"); > fIn.setAccessible(true); > Object realIn = fIn.get(this.in); > // In hadoop 0.22, DFSInputStream is a standalone class. Before > this, > // it was an inner class of DFSClient. > if (realIn.getClass().getName().endsWith("DFSInputStream")) { > Method getFileLength = realIn.getClass(). > getDeclaredMethod("getFileLength", new Class<?> []{}); > getFileLength.setAccessible(true); > long realLength = ((Long)getFileLength. > invoke(realIn, new Object []{})).longValue(); > assert(realLength >= this.length); > adjust = realLength - this.length; > } else { > LOG.info("Input stream class: " + realIn.getClass().getName() + > ", not adjusting length"); > } > } catch(Exception e) { > SequenceFileLogReader.LOG.warn( > "Error while trying to get accurate file length. " + > "Truncation / data loss may occur if RegionServers die.", e); > } > return adjust + super.getPos(); > {code} -- This message was sent by Atlassian JIRA (v6.3.4#6332)