code: package com.hrLDA.doc;
  
  import java.io.File;
  
  import org.apache.commons.io.FileUtils;
  
  
  public class StripTXTContent extends Document{
  	public StripTXTContent(){}
      /**
       * 
       * @param .txt file
       * @return text content
       * @throws Exception
       */
      public StripTXTContent readContent(File file) {
  //    	StripTXTContent stripTXTContent = new StripTXTContent();
      	try{
      		String temp = FileUtils.readFileToString(file);
      		temp = temp.replaceAll("\\[.*\\]","");// This is for Wiki articles 
              if (!temp.matches("\\s+") && !temp.matches("")){
                  setCont(temp);
                  return this;
              }else return null;
  
  		} catch (Exception e) {
      			return null;
  		}
     }	
  	public static void main(String[] args) {
  		// TODO Auto-generated method stub
  		Document stripTXTContent = new StripTXTContent();
  		File file = new File ("/Users/xiaofengzhu/Documents/Intel/Materials/wikippts/Wiki0/Chip.txt");
  		stripTXTContent.readContent(file);
  		System.out.println(stripTXTContent.getCont());
  	}
  
  }
  