Hadoop sequencefile using Hadoop 2 Apis

 Public classsequencefilestest {@Test Public voidTestseqfilereadwrite ()throwsIOException {Configuration conf=NewConfiguration (); FileSystem FS=filesystem.getlocal (conf); Path Seqfilepath=NewPath ("File.seq"); Sequencefile.writer Writer=sequencefile.createwriter (conf, Writer.file (Seqfilepath), Writer.keyclass (Text.class), Writer.valueclass (intwritable.class)); Writer.append (NewText ("Key1"),NewIntwritable (1)); Writer.append (NewText ("Key2"),NewIntwritable (2));    Writer.close (); Sequencefile.reader Reader=Newsequencefile.reader (conf, Reader.file (Seqfilepath)); Text Key=NewText (); Intwritable Val=Newintwritable ();  while(Reader.next (Key, Val)) {System.err.println ( key+ "\ T" +val);  } reader.close (); }}

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ImportJava.io.File;Importjava.io.IOException;ImportJava.io.RandomAccessFile;Importorg.apache.hadoop.conf.Configuration;ImportOrg.apache.hadoop.fs.Path;Importorg.apache.hadoop.io.BytesWritable;Importorg.apache.hadoop.io.IOUtils;ImportOrg.apache.hadoop.io.SequenceFile;Importorg.apache.hadoop.io.SequenceFile.Reader.Option;ImportOrg.apache.hadoop.io.Text;Importorg.apache.hadoop.io.Writable;Importorg.apache.hadoop.util.ReflectionUtils; Public classSequencefileoperator {PrivateConfiguration conf =NewConfiguration (); /*private FileSystem FS;        {try {fs = Filesystem.get (Uri.create ("hdfs://cldx-1336-1202:9000"), conf);        } catch (IOException e) {//TODO auto-generated catch block E.printstacktrace (); }    }*/     Public Static voidMain (string[] args)throwsIOException {//TODO auto-generated Method Stub        if(args = =NULL|| Args.length < 2) {System.out. println ("Following is the possible invocations <operation id> <arg1> <arg2> ..."); System.out. println ("1 <absolute path of directory containing documents> ); System.out.println ("2 ); return; }        intOperation = Integer.valueof (args[0]); Sequencefileoperator Doctoseqfilewriter=NewSequencefileoperator (); Switch(operation) { Case1: {String Docdirectorypath= Args[1]; String Sequencefilepath= Args[2]; System.out.println ("Writing files present at" +Docdirectorypath+ "to the sequence file" +Sequencefilepath);            Doctoseqfilewriter.loaddocumentstosequencefile (Docdirectorypath, Sequencefilepath);  Break; }         Case2: {String Sequencefilepath= Args[1]; System.out.println ("Reading the sequence file" +Sequencefilepath);            Doctoseqfilewriter.readsequencefile (Sequencefilepath);  Break; }        }    }    Private voidReadsequencefile (String Sequencefilepath)throwsIOException {//TODO auto-generated Method Stub        /** Sequencefile.reader sequencefilereader = new Sequencefile.reader (FS, * new Path (Sequencefilepath),         conf); */Option FilePath= SequenceFile.Reader.file (NewPath (Sequencefilepath)); Sequencefile.reader Sequencefilereader=Newsequencefile.reader (conf, filePath); Writable Key=(writable) reflectionutils.newinstance (Sequencefilereader.getkeyclass (), Conf); Writable Value=(writable) reflectionutils.newinstance (Sequencefilereader.getvalueclass (), Conf); Try {             while(Sequencefilereader.next (key, value)) {System.out. printf ("[%s]%s%s \ n", Sequencefilereader.getposition (), Key, Value.getclass (            )); }        } finally{ioutils.closestream (sequencefilereader); }    }    Private voidloaddocumentstosequencefile (String docdirectorypath, string sequencefilepath)throwsIOException {//TODO auto-generated Method StubFile docdirectory=NewFile (Docdirectorypath); if(!docdirectory.isdirectory ()) {System.out. println ("Provide an absolute path of a directory that contains the documents to be added to the sequence file"); return; }        /** Sequencefile.writer sequencefilewriter = * Sequencefile.createwriter (FS, Conf, new Path (Sequencefil         Epath), * text.class, Byteswritable.class); */org.apache.hadoop.io.SequenceFile.Writer.Option FilePath=sequencefile.writer. File (NewPath (Sequencefilepath)); Org.apache.hadoop.io.SequenceFile.Writer.Option Keyclass=sequencefile.writer. Keyclass (Text.class); Org.apache.hadoop.io.SequenceFile.Writer.Option Valueclass=sequencefile.writer. Valueclass (byteswritable.class); Sequencefile.writer Sequencefilewriter=sequencefile.createwriter (conf, FilePath, Keyclass, Valueclass); File[] Documents=Docdirectory.listfiles (); Try {             for(File document:documents) {Randomaccessfile RAF=NewRandomaccessfile (document, "R"); byte[] content =New byte[(int) Raf.length ()];                raf.readfully (content); Sequencefilewriter.append (NewText (Document.getname ()),Newbyteswritable (content));            Raf.close (); }        } finally{ioutils.closestream (sequencefilewriter); }    }}

Hadoop sequencefile using Hadoop 2 Apis