Memory-mapped file mode (Mappedbytebuffer) handles an instance of a file

Package org.phoenix.cases.kafka;import java.io.file;import java.io.filenotfoundexception;import  java.io.FileReader;import java.io.IOException;import java.io.RandomAccessFile;import  java.nio.mappedbytebuffer;import java.nio.channels.filechannel;import org.apache.commons.io.ioutils; import org.apache.commons.io.lineiterator;import org.junit.test;/** *  a memory-mapped file to handle an instance of a file  *  @author  mengfeiyang * */public class mappedbytes { string  filePath =  "e:\\ working directory \ \ New project \ \ Feng Dance phase \\backup\\new_show_style_json.txt";   /**   *  instance of the memory-mapped file processing file   *  @throws  FileNotFoundException  *  @throws  IOException  */  @SuppressWarnings ("resource")   @Test  public void  Testmappedbyte ()  throws filenotfoundexception, ioexception {  long start  = system.currenttimemilliS ();   file file = new file (FilePath);   long filelength =  file.length ();   final int buffer_size=0x500000;//5m  mappedbytebuffer  inputbuffer = new randomaccessfile (file, "RW"). Getchannel (). Map (FileChannel.MapMode.READ_ Write, 0, filelength);  byte[] dst = new byte[buffer_size];   int count=0;  for (Int offset=0;offset<filelength;offset += buffer_size) {            if  (fileLength -  Offset >= buffer_size)  {                     for  (int i = 0; i <  buffer_size; i++)                     &nbsP;    dst[i] = inputbuffer.get (offset + i);                 } else {                     for   (int i = 0; i < filelength - offset; i++)                           dst[i] = inputbuffer.get (offset + i);                 }                 string bs = new string (DST, " UTF-8 ");//Convert bytes in buffer to string             string[]  ns = bs.split ("\ n");Nbsp;           for (String s : ns) {              if (S.contains (")") {               count++;               system.out.println (S.split ("a") [0]);              }             }                        system.out.println ();             //string s = ioutils.tostring (new  Bytearrayinputstream (DST));             // System.out.println (s);   } &nBsp SYSTEM.OUT.PRINTLN ("Total number of processing strips:" +count);   long end = system.currenttimemillis ();    system.out.println ((End - start)/1000);//processing 809M files, 90,000 data, only 6 seconds  }  }}

Memory-mapped file mode (Mappedbytebuffer) handles an instance of a file