Java useful programs

Get file list from a folder filtered by extensions

package com.java2novice.files;

import java.io.File;

import java.io.FilenameFilter;

 public class MyFilteredFileList

{

    public static void main(String a[])

    {

        File file = new File("C:/MyFolder/");

        File[] files = file.listFiles(new FilenameFilter()

        {          

                   public boolean accept(File dir, String name)

                       {

                if(name.toLowerCase().endsWith(".csv"))

                {

                    return true;

                }

                else

                {

                    return false;

                }

            }

        });

        for(File f:files)

        {

            System.out.println(f.getName());

        }

    }

}

Read input from java console in java

package com.java2novice.files;

import java.io.BufferedReader;

import java.io.IOException;

import java.io.InputStreamReader;

import java.io.Reader;

public class ReadFromConsole

{

    public static void main(String a[])

    {

        BufferedReader br = null;

        Reader r = new InputStreamReader(System.in);

        br = new BufferedReader(r);

        String str = null;

        try

            {

            do

               {

                System.out.println("Enter Input, exit to quit.");

                str = br.readLine();

                System.out.println(str);

            }

             while (!str.equalsIgnoreCase("exit"));

           }

            catch (IOException e)

            {

            e.printStackTrace();

        }

          finally

           {

            try

               {

                if(br != null) br.close();

            }

           catch(Exception ex){}

        }

    }

}

Read property file in static context

package com.java2novice.files;

import java.io.IOException;

import java.io.InputStream;

import java.util.Properties;

public class ClassLoaderFileLoading

 {

           private static Properties appProp = null;

     

    static

           {

        try

            {

 InputStream is=ClassLoaderFileLoading.class. getResourceAsStream("/FileName.properties");

            appProp = new Properties();

            appProp.load(is);

        }

        catch(IOException ex)

         {

            ex.printStackTrace();

        }

         catch(Exception ex)

          {

            ex.printStackTrace();

        }

    }

}

Read file content line by line in java

package com.java2novice.files;

import java.io.BufferedReader;

import java.io.FileNotFoundException;

import java.io.FileReader;

import java.io.IOException;

public class ReadLinesFromFile

{

          public static void main(String a[])

                  {

        BufferedReader br = null;

        String strLine = "";

        try

         {

            br = new BufferedReader( new FileReader("fileName"));

            while( (strLine = br.readLine()) != null)

            {

                System.out.println(strLine);

            }

        }

        catch (FileNotFoundException e)

        {

            System.err.println("Unable to find the file: fileName");

        }

         catch (IOException e)

        {

            System.err.println("Unable to read the file: fileName");

        }

    }

}