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  1. /* package whatever; // don't place package name! */
  2.  
  3. import java.util.*;
  4. import java.lang.*;
  5. import java.io.*;
  6.  
  7. /* Name of the class has to be "Main" only if the class is public. */
  8. class Ideone
  9. {
  10. 	 public static void main(String[] args) {
  11.         ReadFileLast rf = new ReadFileLast();
  12.         File file = new File("/Users/nikhil.agrawal/repo/dropwizard-getting-started/src/main/java/com/javaeeeee/dwstart/ReadingLastNLinesfromLogFile/file.txt");
  13.         // calling method
  14.         rf.readFromLast(file);
  15.         //rf.reverseLines(file);
  16.  
  17.     }
  18.  
  19.     // Read last line of the file
  20.     public void readFromLast(File file){
  21.  
  22.         int lines = 0;
  23.         StringBuilder builder = new StringBuilder();
  24.         RandomAccessFile randomAccessFile = null;
  25.         try {
  26.             randomAccessFile = new RandomAccessFile(file, "r");
  27.             long fileLength = file.length() - 1;
  28.             // Set the pointer at the last of the file
  29.             randomAccessFile.seek(fileLength);
  30.             for(long pointer = fileLength; pointer >= 0; pointer--){
  31.                 randomAccessFile.seek(pointer);
  32.                 char c;
  33.                 // read from the last one char at the time
  34.                 c = (char)randomAccessFile.read();
  35.                 // break when end of the line
  36.                 if(c == '\n'){
  37.                     break;
  38.                 }
  39.                 builder.append(c);
  40.             }
  41.             // Since line is read from the last so it
  42.             // is in reverse so use reverse method to make it right
  43.             builder.reverse();
  44.             System.out.println("Line - " + builder.toString());
  45.         } catch (FileNotFoundException e) {
  46.             // TODO Auto-generated catch block
  47.             e.printStackTrace();
  48.         }
  49.         catch (IOException e) {
  50.             // TODO Auto-generated catch block
  51.             e.printStackTrace();
  52.         }finally{
  53.             if(randomAccessFile != null){
  54.                 try {
  55.                     randomAccessFile.close();
  56.                 } catch (IOException e) {
  57.                     // TODO Auto-generated catch block
  58.                     e.printStackTrace();
  59.                 }
  60.             }
  61.         }
  62.     }
  63. }
Compilation error #stdin compilation error #stdout 0s 0KB
comments (?)
stdin 
Standard input is empty
compilation info 
Main.java:11: error: cannot find symbol
        ReadFileLast rf = new ReadFileLast();
        ^
  symbol:   class ReadFileLast
  location: class Ideone
Main.java:11: error: cannot find symbol
        ReadFileLast rf = new ReadFileLast();
                              ^
  symbol:   class ReadFileLast
  location: class Ideone
2 errors
stdout 
Standard output is empty
https://ideone.com/cJSByU
language:
Java (HotSpot 12)
created:
8 years ago
visibility:
public

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