How to read a specific line of a .dat file?

can we read a specific line of a .dat file, if so, how?
i have this .dat files for each customer, which contain their name on the first line, their id on the second line
and a list of items and an item id between each item.
John Doe
455689
milk
1
orange
9
Here is what I am trying to do, please correct me
//list out .dat file in dir
File customer_dir = new File ("Customer")
if (customer_dir.isDirectory())
String[] listofdat=dir.list();
for (int i=0;i<listofdat.length();i++)
Scanner dat_read = new Scanner (new File listfodat);
dat_read.nextLine();
if (dat_read.nextLine().equals("455689")) <--is this okay?

bibiancheng wrote:
would you please explain to me what
String[] tokens = line.trim().split("\\s*,\\s*")"\\s*,\\s*" is a regex where \\s means whitespace and the * means "any number of".
so \\s* means that it will grab all the whitespace if there is any.
trim() removes white space from the beginning and end of the string.
dont put a comma in the name.
spaces allowed: "jane doe, 12-14-09, 428438, 6, 388473, 7, 187374, 3"
it was just a recommendation. breaking it into separate lines would be fine.

Similar Messages

How to read the last line in a txt file?

Dear all,
I want to read the last line in a txt file. There are thousands of lines in this file. What I want is to move the file pointer directly to the last line of the file. But I did not know how do to it. Can anybody help me out?
Thank you very much!

If the file is coded as ASCII or one of the encodings that maps a single byte to a char then the following class will assist you
import java.io.*;
import java.util.*;
public class GetLinesFromEndOfFile
    static public class BackwardsFileInputStream extends InputStream
        public BackwardsFileInputStream(File file) throws IOException
            assert (file != null) && file.exists() && file.isFile() && file.canRead();
            raf = new RandomAccessFile(file, "r");
            currentPositionInFile = raf.length();
            currentPositionInBuffer = 0;
        public int read() throws IOException
            if (currentPositionInFile <= 0)
                return -1;
            if (--currentPositionInBuffer < 0)
                currentPositionInBuffer = buffer.length;
                long startOfBlock = currentPositionInFile - buffer.length;
                if (startOfBlock < 0)
                    currentPositionInBuffer = buffer.length + (int)startOfBlock;
                    startOfBlock = 0;
                raf.seek(startOfBlock);
                raf.readFully(buffer, 0, currentPositionInBuffer);
                return read();
            currentPositionInFile--;
            return buffer[currentPositionInBuffer];
        public void close() throws IOException
            raf.close();
        private final byte[] buffer = new byte[4096];
        private final RandomAccessFile raf;
        private long currentPositionInFile;
        private int currentPositionInBuffer;
    public static List<String> head(File file, int numberOfLinesToRead) throws IOException
        return head(file, "ISO-8859-1" , numberOfLinesToRead);
    public static List<String> head(File file, String encoding, int numberOfLinesToRead) throws IOException
        assert (file != null) && file.exists() && file.isFile() && file.canRead();
        assert numberOfLinesToRead > 0;
        assert encoding != null;
        LinkedList<String> lines = new LinkedList<String>();
        BufferedReader reader= new BufferedReader(new InputStreamReader(new FileInputStream(file), encoding));
        for (String line = null; (numberOfLinesToRead-- > 0) && (line = reader.readLine()) != null;)
            lines.addLast(line);
        reader.close();
        return lines;
    public static List<String> tail(File file, int numberOfLinesToRead) throws IOException
        return tail(file, "ISO-8859-1" , numberOfLinesToRead);
    public static List<String> tail(File file, String encoding, int numberOfLinesToRead) throws IOException
        assert (file != null) && file.exists() && file.isFile() && file.canRead();
        assert numberOfLinesToRead > 0;
        assert (encoding != null) && encoding.matches("(?i)(iso-8859|ascii|us-ascii).*");
        LinkedList<String> lines = new LinkedList<String>();
        BufferedReader reader= new BufferedReader(new InputStreamReader(new BackwardsFileInputStream(file), encoding));
        for (String line = null; (numberOfLinesToRead-- > 0) && (line = reader.readLine()) != null;)
            // Reverse the order of the characters in the string
            char[] chars = line.toCharArray();
            for (int j = 0, k = chars.length - 1; j < k ; j++, k--)
                char temp = chars[j];
                chars[j] = chars[k];
                chars[k]= temp;
            lines.addFirst(new String(chars));
        reader.close();
        return lines;
    public static void main(String[] args)
        try
            File file = new File("/usr/share/dict/words");
            int n = 10;
                System.out.println("Head of " + file);
                int index = 0;
                for (String line : head(file, n))
                    System.out.println(++index + "\t[" + line + "]");
                System.out.println("Tail of " + file);
                int index = 0;
                for (String line : tail(file, "us-ascii", n))
                    System.out.println(++index + "\t[" + line + "]");
        catch (Exception e)
            e.printStackTrace();
}Note, the EOL characters are treated as line separators so you will probably need to read the last two lines (think about it for a bit).

Read a specific line of a txt file using vba not using line by line, Leer una Linea especifica de archivo de texto sin recorrer linea por linea

Buenos días - Good morning
Mi pregunta la escribiré en español y en ingles y espero alguien tenga la solución.
I'll write my question in Spanish and English and I hope someone has the solution.
SPANISH
Creé una Macro en VBA que lee mas de 200.000 archivos de texto (.txt) los cuales tienen diferentes tamaños y cantidad de información dentro de ellos, de cada archivo necesito extraer la información de las 3 primeras lineas y las ultimas 10 lineas, las 3
primeras lineas es fácil ya que uso un "READLINE" 3 veces y voy capturando la información de las tres primeras lineas, para las ultimas 10 lineas las cuales están identificadas por un código inicial hago un ciclo que lee linea por linea hasta que
encuentra el numero 3 en un espacio especificado de la linea y de ahí captura la información de cada linea de texto que serian las 10 ultimas, el problema que tengo es que la cantidad de archivos y de información dentro de los archivos aumenta considerablemente
cada día y por tener el ciclo que lee cada una de las lineas de cada archivo de texto la Macro se demora cada vez mas a medida que aumenta la información y consume cada vez mas memoria de la maquina.
Necesito un método diferente que no lea linea por linea y que yo le pueda decir lea la linea (renglón) numero 1000 (ejemplo) y capture la información a partir de ahí para ahorrar algo de tiempo, o saber cuantas lineas de texto tiene el archivo .txt y decirle
que me lea a partir de (numero total de lineas del txt -(menos) 10 lineas) así me leería las 10 ultimas.
ENGLISH
I created a Macro in VBA that reads more than 200,000 text files (.txt) which have different sizes and quantity of information within them, each file need to extract the information from the first 3 lines and last 10 lines, 3 first lines is easy as using a
'READLINE "3 times and am capturing information from the first three lines, for the last 10 lines which are identified by an initial code I make a loop that reads line by line until it finds the number 3 in a specified area of the line and then capture
the information of each line of text that would be 10 last, the problem that I have is that the number of files and information within files significantly increases every day and having the loop that reads each line of each text file is delayed Macro increasingly
as more information and consume more and more memory on the machine.
I Need a different method not read line by line and I can tell you read the line (row) number 1000 (example) and capture the information from there to save some time or know how many lines of text have the file .txt and tell me read from (total number of lines
of txt - (minus) 10 lines) so I would read 10 last.
Here is the code I currently use
Dejo el código que uso actualmente
Dim fs, f, ts, REG
Set fso = CreateObject("Scripting.FileSystemObject")
On Error Resume Next
sFilePath = strFolder & "\" & strFileName
Set f = fso.getFile(sFilePath)
Set ts = f.OpenAsTextStream(1, 0)
REG = ts.READLINE
Ciclo para llegar hasta las ultimas 10 lineas
Cycle to reach the last 10 lines
For J = 1 To 200000
REG = ts.READLINE
If Val(Mid(REG, 6, 1)) = 3 Then

Good Morning ryguy72
First thank you so much for your answer, sorry for my english in the question, I tried for a long time to make a code that wasn't so slow to read the last 10 lines, 'cuz most codes used a cycle "For" to read line by line asking if in the specific
position is the character(number) that tells me that i should get started to read the last lines that i need, that takes a lot longer than your code doing a Split with Mydata and storing it in strData(). I don't know how to do this and every forum that
i consulted to read the last 10 lines quickly they made the same read line by line with a Cycle "for".
Thanks again, I gonna improve my code with your help, 'cuz it took about 4 hours to read all the information and everyday ascended more time and memory consumption.
Thanks to everyone who offered their help so disinterested and free, so should always be people with that spirit, I hope someday to be SO good as you programming.

How to read the second line in a .txt file with bufferedReader?

hi,
i am not the best in speaking english and programming java :)
so, just try to make sense of my question:
Im using a BufferedReader to read a .txt file.
the .txt file has 5+ different lines, and each line has 6 tokens (separated with ; )
My java file has 6 textFields and each textfield is filled with one of the 6 different tokens.
and my problem is:
I want my buffered reader to read the next line (with 6 new different tokens) by pressing a button.
if somethings not understandable, just ask :)

maybe its easier to help me, when i publish my code, so here it is:
(its my version, without Thof's code. Sorry, but the comments are the most in german)
/* userdata.java */
import java.awt.*;
import java.awt.event.*;
import java.applet.*;
import javax.swing.*;
import java.util.*;
import java.io.*;
public class userdata extends Frame {
//-----------------------------------KlassenVariablen------------------------------------------------
private JPanel panel = new JPanel ();
String tokId = "";
String tokName= "";
String tokAge= "";
String tokTel= "";
String tokMail= "";
String tokText= "";
BufferedReader br;
String zeile;
StringTokenizer st;
String delim = ";";
//---------Buttons f?r Panel 1-------------------------
Button first = new Button("|< First");
Button back = new Button("< Back");
Button next = new Button("Next >");
Button last = new Button("Last >|");
//---------Buttons f?r Panel 3-------------------------
Button neu = new Button("New");
Button safe = new Button("Safe");
Button refresh = new Button("Refresh");
//--------Labels f?r Panel 2-----------------------------
Label lid = new Label("ID",Label.LEFT);
Label lname = new Label("Name",Label.LEFT);
Label lage = new Label("Age",Label.LEFT);
Label ltel = new Label("Tel.",Label.LEFT);
Label lmail = new Label("E-Mail",Label.LEFT);
Label ltext = new Label("Spruch",Label.LEFT);
Label lub = new Label("Last Button",Label.LEFT);
TextField id = new TextField();
TextField name = new TextField();
TextField age = new TextField();
TextField tel = new TextField();
TextField mail = new TextField();
TextField text = new TextField();
TextField usedbutton = new TextField();
//--------ActionEvent bla sachen eben--------------------
public static void main (String[] args) throws IOException {
userdata wnd = new userdata();
wnd.setVisible(true);
public userdata() throws IOException {
//--------------------------------Layout mit panel bestimmung--------------------------------------
setLayout(new BorderLayout());
JPanel p1 = new JPanel();
JPanel p2 = new JPanel();
JPanel p3 = new JPanel();
add(BorderLayout.NORTH ,p1);
add(BorderLayout.CENTER , p2);
add(BorderLayout.SOUTH , p3);
//-------------------------------Funktionslose Buttons in PANEL 1------------------------------------
p1.add(first);
p1.add(back);
p1.add(next);
p1.add(last);
p1.add(usedbutton);
//--------------------------------Funktionierende Textfelder in PANEL 2------------------------------
Panel labelpanel = new Panel();
p2.setLayout(new GridLayout(7,3));
p2.add(lid);
p2.add(id);
p2.add(lname);
p2.add(name);
p2.add(lage);
p2.add(age);
p2.add(ltel);
p2.add(tel);
p2.add(lmail);
p2.add(mail);
p2.add(ltext);
p2.add(text);
p2.add(lub);
p2.add(usedbutton);
//--------------------------------------Buttons in PANEL 3-----------------------------------------
p3.add(neu);
p3.add(safe);
p3.add(refresh);
//--------------------------------BufferedReader -------------------------------------------------
readData();
//--------------------------------Panel 2 TextField-----------------------------------------------
fillForm();
//================================ActionPerformed==================================================
first.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed( ActionEvent e ) {
System.out.println ("First");
usedbutton.setText("First");
back.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed( ActionEvent e ) {
System.out.println ("Back");
usedbutton.setText("Back");
next.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed( ActionEvent e ) {
System.out.println ("Next");
usedbutton.setText("Next");
last.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed( ActionEvent e ) {
System.out.println ("Last");
usedbutton.setText("Last");
neu.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed( ActionEvent e ) {
System.out.println ("New entry");
usedbutton.setText("New");
safe.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed( ActionEvent e ) {
System.out.println ("Now Saving, do not turn off!");
usedbutton.setText("Save");
//-----------------refresh
refresh.addActionListener(new java.awt.event.ActionListener() {
public void actionPerformed( ActionEvent e ) {
try{
readData();
}catch( IOException ioe){
System.out.println("Fehler beim lesen aus Datei");
fillForm();
usedbutton.setText("Refresh");
//=============================================================================Button Funktionen!!!
pack();
//--------------------------------WindowsListener hinzuf?gene--------------------------------------
addWindowListener(
new WindowAdapter() {
public void windowClosing(WindowEvent event)
setVisible(false);
dispose();
System.exit(0);
//-----------------------------------readData() - > Buffered Reader in aktion! --------------------
private void readData() throws IOException{
BufferedReader br = new BufferedReader(new FileReader("My .txt File with path"));
String zeile;
StringTokenizer st;
String delim = ";";
zeile = br.readLine();
st = new StringTokenizer(zeile, delim);
st.hasMoreTokens();
//System.out.println (st.nextToken());
tokId = new String(st.nextToken());
tokName = new String (st.nextToken());
tokAge = new String (st.nextToken());
tokTel = new String (st.nextToken());
tokMail = new String (st.nextToken());
tokText = new String (st.nextToken());
//--------------------------fillForm() - > f?llt die TextFelder aus!--------------------------------
private void fillForm(){
id.setText(tokId);
name.setText(tokName);
age.setText(tokAge);
tel.setText(tokTel);
mail.setText(tokMail);
text.setText(tokText);
}

How to read the last line in a text file using text_io?? please help

Dear all
I made a procedure that append text into a text file on the operating system.
the text file grows rapidly. It contains now about 200,000 line . I need to read the last line only . In other wprds i need to go direct to the last line to read some values. Is it possible??
Please help

Hello,
If you know the number of the line you want to read, I can sugget you to use the MORE dos command or the TAIL unix command that redirect to a temporary text file
Example to create a file that contains the 200010th last lines :
(Client)Host( 'MORE the_file_name.txt +200010 > small_file.txt') ;So you have only to read the small file with the TEXT_IO functions.
Francois

How to read from and write to remote data file?

Hi there
I have two variables that I would like to store in a remote data file which can be accessed by my Flash file. It is for a voting system, so the first variable would be a counter that is incremented each time a user votes, and the second would be the total rating. The average rating would then be calculated from these.
How would one store, retrieve, and then update these variables from the data file?
I can create the system within a single Flash file for a single session, but obviously I'd like multiple users opening the file simultaneously to be able to access the data and update it.
I'm using AS2 in CS3. Any help would be appreciated.

Right, I've made significant progress since I started this topic. I now have my Flash and php files set up, and the communication between them is working. I'm having difficulty now retaining my variables in the php and updating them for the next session. The script that I have is as follows:
<?
$totalRating1 += $_POST['latestRating1'];
$ratingCount1 ++;
$averageRating1 = $totalRating1 / $ratingCount1;
echo "&averageRating=$averageRating1";
?>
The first line receives the variable "latestRating1" from the SWF. The new average rating is calculated and returned to the SWF as "averageRating". When I run it, however, the variables are reset each time. The average rating is always the same as the latest rating. How can I retain the variables so that they are updated and available for the next user?
Any advice would be appreciated. I am very new to php, and don't have any experience with other scripting languages. I'm using ActionScript2.

How to only read the last line in the text file by using BufferedReader ?

Dear all,
Hello, I am new to Java. Do anybody know how to read the last line (this is the last record) in the text file.The method I am now using is reading from the first line until I reach the last line in the text file. Thank you!!
BufferedReader br = new BufferedReader(new FileReader("c:\\sdk1.4.1\\bin\\dbExport.txt"));
DataInputStream in = new DataInputStream(new FileInputStream("c:\\sdk1.4.1\\bin\\dbExport.txt"));
String input;
String firstinput;
String secondinput;
int count=90;
int year=1955;
while ((input = br.readLine()) != null) {
firstinput = input.substring(0, 10);
secondinput = input.substring(10);
String insertStore1 = ("INSERT INTO AUTHORS " +
"VALUES ('" + count + "', '" + firstinput + "', '" + secondinput + "', 1955)");
System.out.println(insertStore1);
int result = stmt.executeUpdate(insertStore1);

I suppose you could use a java.io.RandomAccessFile.

How to read a current line in table control in dialoug program ?

How to read a current line in table control in dialoug program ?
this code required to provide F4 help.

Hi,
You can use the variable <tablecontrol>-Currentline as Ebus says but there is a problem with this.Suppose there are 10 records in the table control with only 5 records visible then when u press a page down and press F4 the first record in page 2, <tablecontrol>-Currentline will have value of 1 instead of 6.So you will need to write a small logic for that.
index = ( <tablecontrol>-topline - <tablecontrol>-currentline ) + 1.
read internal table itab at index.
Hope this helps.
Regards,
Vivek

How can I read a specific character from a text file?

Hi All!
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How can I do this?
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Johannes

just use the skip(long) method of the input stream that reads the text file and skip over the desired number of bytes

How to skip first 5 lines from a txt file when using sql*loader

Hi,
I have a txt file that contains header info tat i dont need. how can i skip those line when importing the file to my database?
Cheers

Danny Fasen wrote:
I think most of us would process this report using pl/sql:
- read the file until you've read the column headers
- read the account info and insert the data in the table until you have read the last account info line
- read the file until you've read a new set of column headers (page 2)
- read the account info and insert the data in the table until you have read the last account info line (page 2)
- etc. until you reach the total block idenfitied by Count On-line ...
- read the totals and compare them with the data inserted in the tableOr maybe like this...
First create an external table to read the report as whole lines...
SQL> ed
Wrote file afiedt.buf
1 CREATE TABLE ext_report (
2    line VARCHAR2(200)
3          )
4 ORGANIZATION EXTERNAL (
5    TYPE oracle_loader
6    DEFAULT DIRECTORY TEST_DIR
7    ACCESS PARAMETERS (
8      RECORDS DELIMITED BY NEWLINE
9      BADFILE 'bad_report.bad'
10      DISCARDFILE 'dis_report.dis'
11      LOGFILE 'log_report.log'
12      FIELDS TERMINATED BY X'0D' RTRIM
13      MISSING FIELD VALUES ARE NULL
14      REJECT ROWS WITH ALL NULL FIELDS
15        (
16         line
17        )
18      )
19      LOCATION ('report.txt')
20    )
21 PARALLEL
22* REJECT LIMIT UNLIMITED
SQL> /
Table created.
SQL> select * from ext_report;
LINE
x report page1
CDC:00220 / Sat Aug-08-2009 xxxxp for 02/08/09 - 08/08/09 Effective Date 11/08/09 Wed Sep-30-2009 08:25:43
Bill to
Retailer Retailer Name                  Name on Bank Account           Bank ABA   Bank Acct            On-line Amount Instant Amount Total Amount
======== ============================== ============================== ========== ==================== =============== =============== ===============
0100103 BANK Terminal                  raji                           123456789 123456789            -29,999.98    9 0.00         99 -29,999.98
0100105 Independent 1                  Savings                        123456789 100000002            -1,905.00     9 0.00         99 -1,905.00
0100106 Independent 2                  system                         123456789 100000003            -800.00       9 -15.00       99 -815.00
LARGE SPACE
weekly_eft_repo 1.0 Page: 2
CDC:00220 / Sat Aug-08-2009 Weekly EFT Sweep for 02/08/09 - 08/08/09 Effective Date 11/08/09 Wed Sep-30-2009 08:25:43
Bill to
Retailer Retailer Name Name on Bank Account Bank ABA Bank Acct On-line Amount Instant Amount Total Amount
======== ============================== ============================== ========== ==================== =============== =============== ===============
Count On-line Amount Instant Amount Total Amount
============== ====================== ====================== ======================
Debits 0 0.00 0.00 0.00
Credits 3 -32,704.98 -15.00 -32,719.98
Totals 3 -32,704.98 -15.00 -32,719.98
Total Tape Records / Blocks / Hash : 3 1 37037034
End of Report
23 rows selected.Then we can check we can just pull out the lines of data we're interested in from that...
SQL> ed
Wrote file afiedt.buf
1 create view vw_report as
2* select line from ext_report where regexp_like(line, '^[0-9]')
SQL> /
View created.
SQL> select * from vw_report;
LINE
0100103 BANK Terminal                  raji                           123456789 123456789            -29,999.98    9 0.00         99 -29,999.98
0100105 Independent 1                  Savings                        123456789 100000002            -1,905.00     9 0.00         99 -1,905.00
0100106 Independent 2                  system                         123456789 100000003            -800.00       9 -15.00       99 -815.00And then we adapt that view to extract the data from those lines as actual columns...
SQL> col retailer format a10
SQL> col retailer_name format a20
SQL> col name_on_bank_account format a20
SQL> col online_amount format 999,990.00
SQL> col instant_amount format 999,990.00
SQL> col total_amount format 999,990.00
SQL> ed
Wrote file afiedt.buf
1 create or replace view vw_report as
2 select regexp_substr(line, '[^ ]+', 1, 1) as retailer
3        ,trim(regexp_replace(regexp_substr(line, '[[:alpha:]][[:alnum:] ]*[[:alpha:]]', 1, 1), '(.*) +[^ ]+$', '\1')) as retailer_name
4        ,trim(regexp_replace(regexp_substr(line, '[[:alpha:]][[:alnum:] ]*[[:alpha:]]', 1, 1), '.* ([^ ]+)$', '\1')) as name_on_bank_account
5        ,to_number(regexp_substr(regexp_replace(line,'.*[[:alpha:]]([^[:alpha:]]+)','\1'), '[^ ]+', 1, 1)) as bank_aba
6        ,to_number(regexp_substr(regexp_replace(line,'.*[[:alpha:]]([^[:alpha:]]+)','\1'), '[^ ]+', 1, 2)) as bank_account
7        ,to_number(regexp_substr(regexp_replace(line,'.*[[:alpha:]]([^[:alpha:]]+)','\1'), '[^ ]+', 1, 3),'999,999.00') as online_amount
8        ,to_number(regexp_substr(regexp_replace(line,'.*[[:alpha:]]([^[:alpha:]]+)','\1'), '[^ ]+', 1, 5),'999,999.00') as instant_amount
9        ,to_number(regexp_substr(regexp_replace(line,'.*[[:alpha:]]([^[:alpha:]]+)','\1'), '[^ ]+', 1, 7),'999,999.00') as total_amount
10* from (select line from ext_report where regexp_like(line, '^[0-9]'))
SQL> /
View created.
SQL> select * from vw_report;
RETAILER   RETAILER_NAME        NAME_ON_BANK_ACCOUNT   BANK_ABA BANK_ACCOUNT ONLINE_AMOUNT INSTANT_AMOUNT TOTAL_AMOUNT
0100103    BANK Terminal        raji                  123456789    123456789    -29,999.98           0.00   -29,999.98
0100105    Independent 1        Savings               123456789    100000002     -1,905.00           0.00    -1,905.00
0100106    Independent 2        system                123456789    100000003       -800.00         -15.00      -815.00
SQL>I couldn't quite figure out the "9" and the "99" data that was on those lines so I assume it should just be ignored. I also formatted the report data to fixed columns width in my external text file as I'd assume that's how the data would be generated, not that that would make much difference when extracting the values with regular expressions as I've done.
So... something like that anyway. ;)

How to read a String from a simple text file.

I have a set up popup reminders, the content of which I have entered into a text file. I read the text and display it in a specially formatted JFrame/JPanel.
My question is, since readLine() has been deprecated, how do you read a simple line of text data from a file created by, say, notepad? I guess I could just use readLine() anyway, but I want to learn the language, and "playing by the rules" seems to be the way I should go.

I''m guessing your referring to the readLine method of DataInputStream. Use another class, like BufferedReader, which also happens to have a method named readLine:
BufferedReader in = new BufferedReader(new FileReader(filename));
try {
    String line;
    while ((line = in.readLine()) != null) {
        //process line
} finally {
    in.close();
}

Reading a Random Line from a Text File

Hello,
I have a program that reads from a text file words. I currently have a text file around 800KB of words. The problem is, if I try to load this into an arraylist so I can use it in my application, it takes wayy long to load. I was wondering if there was a way to just read a random line from the text file.
Here is my code, and the text file that the program reads from is called 'wordFile'
import java.awt.*;
import java.awt.geom.*;
import javax.swing.*;
import java.awt.event.*;
import java.io.*;
import java.util.*;
public class WordColor extends JFrame{
     public WordColor(){
          super("WordColor");
          setSize(1000,500);
          setVisible(true);
          add(new WordPanel());
     public static void main(String[]r){
          JFrame f = new WordColor();
class WordPanel extends JPanel implements KeyListener{
     private Graphics2D pane;
     private Image img;
     private char[]characterList;
     private CharacterPosition[]positions;
     private int charcounter = 0;
     private String initialWord;
     private File wordFile = new File("C:\\Documents and Settings\\My Documents\\Java\\projects\\WordColorWords.txt");
     private FontMetrics fm;
     private javax.swing.Timer timer;
     public final static int START = 20;
     public final static int delay = 10;
     public final static int BOTTOMLINE = 375;
     public final static int buffer = 15;
     public final static int distance = 4;
     public final static Color[] colors = new Color[]{Color.red,Color.blue,Color.green,Color.yellow,Color.cyan,
                                                                      Color.magenta,Color.orange,Color.pink};
     public static String[] words;
     public static int descent;
     public static int YAXIS = 75;
     public static int SIZE = 72;
     public WordPanel(){
          words = readWords();
          setLayout(new BorderLayout());
          initialWord = getWord();
          characterList = new char[initialWord.length()];
          for (int i=0; i<initialWord.length();i++){
               characterList[i] = initialWord.charAt(i);
          setFocusable(true);
          addKeyListener(this);
          timer = new javax.swing.Timer(delay,new ActionListener(){
               public void actionPerformed(ActionEvent evt){
                    YAXIS += 1;
                    drawWords();
                    if (YAXIS + descent - buffer >= BOTTOMLINE) lose();
                    if (allColorsOn()) win();
     public void paintComponent(Graphics g){
          super.paintComponent(g);
          if (img == null){
               img = createImage(getWidth(),getHeight());
               pane = (Graphics2D)img.getGraphics();
               pane.setColor(Color.white);
               pane.fillRect(0,0,getWidth(),getHeight());
               pane.setFont(new Font("Arial",Font.BOLD,SIZE));
               pane.setColor(Color.black);
               drawThickLine(pane,getWidth(),5);
               fm = g.getFontMetrics(new Font("Arial",Font.BOLD,SIZE));
               descent = fm.getDescent();
               distributePositions();
               drawWords();
               timer.start();
          g.drawImage(img,0,0,this);
     private void distributePositions(){
          int xaxis = START;
          positions = new CharacterPosition[characterList.length];
          int counter = 0;
          for (char c: characterList){
               CharacterPosition cp = new CharacterPosition(c,xaxis, Color.black);
               positions[counter] = cp;
               counter++;
               xaxis += fm.charWidth(c)+distance;
     private void drawThickLine(Graphics2D pane, int width, int thickness){
          pane.setColor(Color.black);
          for (int j = BOTTOMLINE;j<BOTTOMLINE+1+thickness;j++){
               pane.drawLine(0,j,width,j);
     private void drawWords(){
          pane.setColor(Color.white);
          pane.fillRect(0,0,getWidth(),getHeight());
          drawThickLine(pane,getWidth(),5);
          for (CharacterPosition cp: positions){
               int x = cp.getX();
               char print = cp.getChar();
               pane.setColor(cp.getColor());
               pane.drawString(""+print,x,YAXIS);
          repaint();
     private boolean allColorsOn(){
          for (CharacterPosition cp: positions){
               if (cp.getColor() == Color.black) return false;
          return true;
     private Color randomColor(){
          int rand = (int)(Math.random()*colors.length);
          return colors[rand];
     private void restart(){
          charcounter = 0;
          for (CharacterPosition cp: positions){
               cp.setColor(Color.black);
     private void win(){
          timer.stop();
          newWord();
     private void newWord(){
          pane.setColor(Color.white);
          pane.fillRect(0,0,getWidth(),getHeight());
          repaint();
          drawThickLine(pane,getWidth(),5);
          YAXIS = 75;
          initialWord = getWord();
          characterList = new char[initialWord.length()];
          for (int i=0; i<initialWord.length();i++){
               characterList[i] = initialWord.charAt(i);
          distributePositions();
          charcounter = 0;
          drawWords();
          timer.start();
     private void lose(){
          timer.stop();
          pane.setColor(Color.white);
          pane.fillRect(0,0,getWidth(),getHeight());
          pane.setColor(Color.red);
          pane.drawString("Sorry, You Lose!",50,150);
          repaint();
          removeKeyListener(this);
          final JPanel p1 = new JPanel();
          JButton again = new JButton("Play Again?");
          p1.add(again);
          add(p1,"South");
          p1.setBackground(Color.white);
          validate();
          again.addActionListener(new ActionListener(){
               public void actionPerformed(ActionEvent evt){
                    remove(p1);
                    addKeyListener(WordPanel.this);
                    newWord();
     private String getWord(){
          int rand = (int)(Math.random()*words.length);
          return words[rand];
     private String[] readWords(){
          ArrayList<String> arr = new ArrayList<String>();
          try{
               BufferedReader buff = new BufferedReader(new FileReader(wordFile));
               try{
                    String line = null;
                    while (( line = buff.readLine()) != null){
                         line = line.toUpperCase();
                         arr.add(line);
               finally{
                    buff.close();
          catch(Exception e){e.printStackTrace();}
          Object[] objects = arr.toArray();
          String[] words = new String[objects.length];
          int count = 0;
          for (Object o: objects){
               words[count] = (String)o;
               count++;
          return words;
     public void keyPressed(KeyEvent evt){
          char tempchar = evt.getKeyChar();
          String character = ""+tempchar;
          if (character.equalsIgnoreCase(""+positions[charcounter].getChar())){
               positions[charcounter].setColor(randomColor());
               charcounter++;
          else if (evt.isShiftDown()){
               evt.consume();
          else{
               restart();
          drawWords();
     public void keyTyped(KeyEvent evt){}
     public void keyReleased(KeyEvent evt){}
class CharacterPosition{
     private int xaxis;
     private char character;
     private Color color;
     public CharacterPosition(char c, int x, Color col){
          xaxis = x;
          character = c;
          color = col;
     public int getX(){
          return xaxis;
     public char getChar(){
          return character;
     public Color getColor(){
          return color;
     public void setColor(Color c){
          color = c;
}

I thought that maybe serializing the ArrayList might be faster than creating the ArrayList by iterating over each line in the text file. But alas, I was wrong. Here's my code anyway:
class WordList extends ArrayList<String>{
long updated;
WordList readWordList(File file) throws Exception{
WordList list = new WordList();
BufferedReader in = new BufferedReader(new FileReader(file));
String line = null;
while ((line = in.readLine()) != null){
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in.close();
list.updated = file.lastModified();
return list;
WordList wordList;
File datFile = new File("words.dat");
File txtFile = new File("input.txt");
if (datFile.exists()){
ObjectInputStream input = new ObjectInputStream(new FileInputStream(datFile));
wordList = (WordList)input.readObject();
if (wordList.updated < txtFile.lastModified()){
    //if the text file has been updated, re-read it
    wordList = readWordList(txtFile);
    ObjectOutputStream output = new ObjectOutputStream(new FileOutputStream(datFile));
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//serialized list does not exist--create it
wordList = readWordList(txtFile);
ObjectOutputStream output = new ObjectOutputStream(new FileOutputStream(datFile));
output.writeObject(wordList);
output.close();
}The text file contained one random sequence of letters per line. For example:
hwnuu
nhpgaucah
zfbylzt
hwnc
gicgwkhStats:
Text file size: 892K
Serialized file size: 1.1MB
Time to read from text file: 795ms
Time to read from serialized file: 1216ms

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Please tell me how to read and update the values from property file using Properties class
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Values
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Now i need to change the value of the SMTP
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