BE THE CODER > Tools and Libs > Google Guava Examples > IO

Google Guava is a java library with lot of utilities and reusable components. This requires the library guava-10.0.jar to be in classpath. The following example shows using Files.readLines() API.

File Name :	com/bethecoder/tutorials/guava/io_tests/ReadLineProcessorTest.java
Author :	Sudhakar KV
Email :	[email protected]


package com.bethecoder.tutorials.guava.io_tests;



import java.io.File;

import java.io.IOException;



import com.google.common.base.Charsets;

import com.google.common.io.Files;

import com.google.common.io.LineProcessor;



public class ReadLineProcessorTest {



  /**

   * @param args

   * @throws IOException 

   */

  public static void main(String[] args) throws IOException {

    File file = new File("C:\\abcd.txt");

    String first4lines = Files.readLines(file, Charsets.UTF_8, new SimpleLineProcessor());

    System.out.println(first4lines);

  }

}



class SimpleLineProcessor implements LineProcessor<String> {



  StringBuilder lineBuf = new StringBuilder();

  private int lineCount = 0;

  

  @Override

  public String getResult() {

    return lineBuf.toString();

  }



  @Override

  public boolean processLine(String line) throws IOException {



    //read only first 2 lines

    //true to continue processing, false to stop

    if (lineCount ++ < 2) {

      lineBuf.append(line).append("\n");

      return true;

    }

    

    return false;

  }

  

}

Readline Processor