!! help using: public static Boolean valueOf(String s)

I am trying to use this simple function to convert a string value to a boolean. According to the documentation for this Boolean method (public static Boolean valueOf(String s)), this should work:
Example: Boolean.valueOf("True") returns true.
As a test, I tried to run this line of code:
tmp_bool = Boolean.valueOf("True");
I get this compilation error:
test_file.java:10: incompatible types
found : java.lang.Boolean
required: boolean
tmp_bool = Boolean.valueOf("True");
.....................................^
According to the documentation for SDK 1.4, there is a new function:
public static Boolean valueOf(boolean b)
It seems like the commpiler is focusing on this new version of the valueOf() method, and ignoring the case where a String is the parameter. Why won't it use the version that takes a String? What confuses me even more is that I am running version 1.3.1, and the new valueOf(boolean b) function is not mentioned in its documentation.
Am I somehow using the method wrong?
Thanks!

OK, I think I understand now. Thanks.
Let me make sure i have this right...
So basically, if you use variable types of Boolean and need to pass them to methods that take booleans, would you have to call the booleanValue method first?
ex:
Boolean bool_obj;
//example method that takes a boolean
//test_method(boolean b);
test_method ( bool_obj.booleanValue() );
is that right?

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Public static boolean contains(string s, string t)

i am just a beginner to java....plz help me out...this is my first time programming.

Is it possibly also your first time posting a question on a technical forum?
Try asking a question.

How to call java with public static void main(String[] args) throws by jsp?

how do i call this from jsp? <%spServicelnd temp = new spServicelnd();%> does not work because the program has a main. can i make another 2nd.java to call this spServiceInd.java then call 2nd.java by jsp? if yes, how??? The code is found below...
import java.net.MalformedURLException;
import java.io.IOException;
import com.openwave.wappush.*;
public class spServiceInd
     private final static String ppgAddress = "http://devgate2.openwave.com:9002/pap";
     private final static String[] clientAddress = {"1089478279-49372_devgate2.openwave.com/[email protected]"};
//     private final static String[] clientAddress = {"+639209063665/[email protected]"};
     private final static String SvcIndURI = "http://devgate2.openwave.com/cgi-bin/mailbox.cgi";
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          System.out.println("hello cze, I'm inside printResult");
          //Read the response to find out if the Push Submission succeded.
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          if (pushResponse.getResultCode() == 1001)
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In general, classes with main method should be called from command prompt (that's the reason for main method). Remove the main method, put the class in a package and import the apckage in your jsp (java classes should not be in the location as jsps).
When you import the package in jsp, then you can instantiate the class and use any of it's methods or call the statis methods directly:
<%
spServiceInd spsi = new spServiceInd();
spsi.SubmitMsg();
%>

Public static final Comparator String CASE_INSENSITIVE_ORDER

in this declaration..
public static final Comparator<String> CASE_INSENSITIVE_ORDER
what does <String> mean?
thanks!

what does the Comparator do. Look at the API and you would see the following description about the compare method.
public int compare(Object o1,
Object o2)Compares its two arguments for order. Returns a negative integer, zero, or a positive integer as the first argument is less than, equal to, or greater than the second.
The implementor must ensure that sgn(compare(x, y)) == -sgn(compare(y, x)) for all x and y. (This implies that compare(x, y) must throw an exception if and only if compare(y, x) throws an exception.)
The implementor must also ensure that the relation is transitive: ((compare(x, y)>0) && (compare(y, z)>0)) implies compare(x, z)>0.
Finally, the implementer must ensure that compare(x, y)==0 implies that sgn(compare(x, z))==sgn(compare(y, z)) for all z.
It is generally the case, but not strictly required that (compare(x, y)==0) == (x.equals(y)). Generally speaking, any comparator that violates this condition should clearly indicate this fact. The recommended language is "Note: this comparator imposes orderings that are inconsistent with equals."
Now your question is about what <String> is in your declaration. It is the type of the objects which are going to be compared.

Why can't created an object in the "public static void main(String args[])"

Example:
public Class Exp {
public static void main(String args[])
new Exp2();-------------> To Occur Error
Class Exp2 {
public Exp2()

You can't create an inner class within main, because
it is a static method. Inner classes can only be
created by true class methods.This is not correct. You can create an inner class object in a static method. You just have to specify an outer class object that the inner class object should be created within:
Exp2 exp2 = new Exp().new Exp2();

Help with public static final List

I'm having a block here... I want to have a constant List, but I can't figure out how to do it so it actually contains the values I want. It's going to be a list of strings about 40 elements long. Obviously, if I didn't need the final, I'd just do List.add( ), but I need to do it right in the constructor. Thanks for the help.

I guess the problem could be reworded, If I wantedto
put this in a class that would never getinstantiated
how would I initialize the List?You use a static intializer.Ah. I didn't get that out of the question. Thanks for the help.
But here's an example:public class Foo {
    static final java.util.List<String> list = new java.util.ArrayList<String>();
        list.add("one");
        list.add("two");
        list.add("three");
        // etc.
}

Using public static object for locking thread shared resources

Lets Consider the example,
I have two classes
1. Main_Reader -- Read from file
public class Main_Reader
public static object tloc=new object();
public void Readfile(object mydocpath1)
lock (tloc)
string mydocpath = (string)mydocpath1;
StringBuilder sb = new StringBuilder();
using (StreamReader sr = new StreamReader(mydocpath))
String line;
// Read and display lines from the file until the end of
// the file is reached.
while ((line = sr.ReadLine()) != null)
sb.AppendLine(line);
string allines = sb.ToString();
2. MainWriter -- Write the file
public class MainWriter
public void Writefile(object mydocpath1)
lock (Main_Reader.tloc)
string mydocpath = (string)mydocpath1;
// Compose a string that consists of three lines.
string lines = "First line.\r\nSecond line.\r\nThird line.";
// Write the string to a file.
System.IO.StreamWriter file = new System.IO.StreamWriter(mydocpath);
file.WriteLine(lines);
file.Close();
Thread.Sleep(10000);
In main have instatiated two function with two threads.
public string mydocpath = "E:\\testlist.txt"; //Here mydocpath is shared resorces
MainWriter mwr=new MainWriter();
Writefile wrt=new Writefile();
private void button1_Click(object sender, EventArgs e)
Thread t2 = new Thread(new ParameterizedThreadStart(wrt.Writefile));
t2.Start(mydocpath);
Thread t1 = new Thread(new ParameterizedThreadStart(mrw.Readfile));
t1.Start(mydocpath);
MessageBox.Show("Read kick off----------");
For making this shared resource thread safe, i am using a public static field,
public static object tloc=new object(); in class Main_Reader
My Question is ,is it a good approach.
Because i read in one of msdn forums, "avoid locking on a public type"
Is any other approach for making this thread safe.

Hi ,
Since they are easily accessed by all threads, thus you need to apply any kind of synchronization (via locks, signals, mutex, etc).
Mutex:https://msdn.microsoft.com/en-us/library/system.threading.mutex(v=vs.110).aspx
Thread signaling basics:http://stackoverflow.com/questions/2696052/thread-signaling-basics
Best regards,
Kristin
We are trying to better understand customer views on social support experience, so your participation in this interview project would be greatly appreciated if you have time. Thanks for helping make community forums a great place.
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Why Integer.valueOf(String) does not recognize plus sign

The Integer.valueOf(String) works fine with strings like "-1", but does not work with "+1". The following code throws NumberFormatException:
int i = Integer.valueOf( "+1" );
Does anybody know what's the reason for this?
Thanks,
-- LK

Welcome to the forum!
>
The Integer.valueOf(String) works fine with strings like "-1", but does not work with "+1". The following code throws NumberFormatException:
int i = Integer.valueOf( "+1" );
Does anybody know what's the reason for this?
>
The short answer is because it is defined that way.
The place to start for questions like this is the Javadoc.
You don't state what Java version you are using but for 1.6 the 'valueOf' method says this
http://127.0.0.1:8082/resource/jar%3Afile%3A/C%3A/Software/Java/jdk1.6.0_02/jdk-6-doc.zip%21/docs/api/java/lang/Integer.html#valueOf(java.lang.String)
>
valueOf
public static Integer valueOf(String s)
throws NumberFormatExceptionReturns an Integer object holding the value of the specified String. The argument is interpreted as representing a signed decimal integer, exactly as if the argument were given to the parseInt(java.lang.String) method. The result is an Integer object that represents the integer value specified by the string.
>
As you can see the description further refers you to the 'parseInt' method where you will find the answer.
>
parseInt
public static int parseInt(String s)
throws NumberFormatExceptionParses the string argument as a signed decimal integer. The characters in the string must all be decimal digits, except that the first character may be an ASCII minus sign '-' ('\u002D') to indicate a negative value. The resulting integer value is returned, exactly as if the argument and the radix 10 were given as arguments to the parseInt(java.lang.String, int) method.
>
You may have to do a little digging but when you have a question like this you should read the relevant Javadoc sections, search the forum for similar questions, search on the net and then if you still can't figure it out post a thread.

Constant values (public static final String) are not shown??

This has already been posted and no body answered. Any help is appreciated.
In web service is it possible to expose the Constants used in the application. Let say for my web service I need to pass value for Operation, possible values for this are (add, delete, update). Is it possible expose these constant values(add, delete, update) visible to client application accesssing the web service.
Server Side:
public static final String ADD = "ADDOPP";
public static final String DELETE = "DELETEOPP";
public static final String UPDATE = "UPDATEOPP";
client Side: mywebserviceport.setOperation( mywebservicePort.ADD );
thanks
vijay

Sure, you can use JAX-WS and enums.
For example on the server:
@WebService
public class echo {
public enum Status {RED, YELLOW, GREEN}
@WebMethod
public Status echoStatus(Status status) {
return status;
on the client you get.
@WebService(name = "Echo", wsdlLocation ="..." )
public interface Echo {
@WebMethod
public Status echoStatus(
@WebParam(name = "arg0", targetNamespace = "")
Status arg0);
@XmlEnum
public enum Status {
GREEN,
RED,
YELLOW;
public String value() {
return name();
public static Status fromValue(String v) {
return valueOf(v);
}

How can i pass the values to method public static void showBoard(boolean[][

I need x and y to pass to the method
public static void showBoard(boolean[][] board
i am very confused as to why its boolean,i know its an array but does that mean values ar true or false only?Thanks
import java.util.Random;
import java.util.Scanner;
public class Life1
     public static void main(String[] args)
          int x=0;
          int y=0;
          Scanner keyIn = new Scanner(System.in);
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          x = keyIn.nextInt();
          System.out.println("Enter the second dimension of the board : );
          y = keyIn.nextInt();
          boolean[][] board = new boolean[x][y];
          fillBoard(board);
          showBoard(board);
          //Ask the user how many generations to show.
          board = newBoard(board);
          showBoard(board);
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     //Rewrite this method to allow the user to populate the board by entering the
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          int row, col, isAlive;
          Random picker = new Random();
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               for(col = 4; col < 9; col++)
                    if (picker.nextInt(2) == 0)
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                      board[row][col] = true;
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     public static void showBoard(boolean[][] board)
          int row, col;
          System.out.println();
          for(row=0; row < x; row++)
               for(col=0; col<y; col++)
                    if (board[row][col])
                         System.out.print("X");
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               System.out.println();
          System.out.println();
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          int row;
          int col;
          int neighbors;
          boolean[][] newBoard = new boolean[board.length][board[0].length];
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               for(col = 1; col < board[row].length-1; col++)
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                         newBoard[row][col]=false;
                    else if (neighbors > 3)
                         newBoard[row][col] = false;
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                         newBoard[row][col]= board[row][col];
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                         newBoard[row][col] = true;
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               for(col = thisCol - 1; col < thisCol + 2; col++)
                 if (board[row][col])
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               count--;
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          for(row = 0; row < board.length; row++)
               for(col = 0; col < board[row].length; col++)
                    board[row][col] = false;
}

this is what im workin with mabey you can point me in the right directionimport java.util.Random;
/* This class creates an application to simulate John Conway's Life game.
* Output is sent to the System.out object.
* The rules for the Life game are as follows...
* Your final version of the program should explain the game and its use
* to the user.
public class Life
     public static void main(String[] args)
          //Allow the user to specify the board size
          boolean[][] board = new boolean[10][10];
          fillBoard(board);
          showBoard(board);
          //Ask the user how many generations to show.
          board = newBoard(board);
          showBoard(board);
     //This method randomly populates rows 5-9 of the board
     //Rewrite this method to allow the user to populate the board by entering the
     //coordinates of the live cells. If the user requests that cell 1, 1 be alive,
     //your program should make cell 0,0 alive.
     public static void fillBoard(boolean[][] board)
          int row, col, isAlive;
          Random picker = new Random();
          for(row = 4; row < 9; row++)
               for(col = 4; col < 9; col++)
                    if (picker.nextInt(2) == 0)
                      board[row][col] = false;
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                      board[row][col] = true;
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     public static void showBoard(boolean[][] board)
          int row, col;
          System.out.println();
          for(row=0; row < 10; row++)
               for(col=0; col<10; col++)
                    if (board[row][col])
                         System.out.print("X");
                    else
                         System.out.print(".");
               System.out.println();
          System.out.println();
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     public static boolean[][] newBoard(boolean[][] board)
          int row;
          int col;
          int neighbors;
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          makeDead(newBoard);
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               for(col = 1; col < board[row].length-1; col++)
                    neighbors = countNeighbors(row, col, board);
                    //make this work with one less if
                    if (neighbors < 2)
                         newBoard[row][col]=false;
                    else if (neighbors > 3)
                         newBoard[row][col] = false;
                    else if (neighbors == 2)
                         newBoard[row][col]= board[row][col];
                    else
                         newBoard[row][col] = true;
          return newBoard;
     //This method counts the number of neighbors surrounding a cell.
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     public static int countNeighbors(int thisRow, int thisCol, boolean[][] board)
          int count = 0;
          int row, col;
          for (row = thisRow - 1; row < thisRow + 2; row++)
               for(col = thisCol - 1; col < thisCol + 2; col++)
                 if (board[row][col])
                      count++;
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               count--;
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     //This method makes each cell in a board "dead."
     public static void makeDead(boolean[][] board)
          int row, col;
          for(row = 0; row < board.length; row++)
               for(col = 0; col < board[row].length; col++)
                    board[row][col] = false;
}

Why ..we have to use this ? public static void ? please !

hi ...im ibrahim ..and im new here in java nd new in the forum too ...nd please i would like to know ...why
do we use the method
public static void main (String []args)
i mean why ..static nd why public ..why void ....why main ..nd why (string []args)
...why we use it ...always ....hopefully ..im looking for a very clear answer to this ...issue ..?
please help .......!

public - this is the visibility modifier (it means that the body method can be call by any outside method)
static - the method is a static instance of the class. Not sure what exactly it does though.
void - this is the return type. void means that the method returns nothing.
main - the name of the method. It can be anything.
"public static void main" - this is the main method where upon executing the Java program the Java Virtual Machine will try to locate this method within the specifies class to be executed. This is always the first one to run when executing a Java program. None of this word may be changed or the program cannot be run.

Help removing char from midpoint of string using deleteCharAt()

How do you properly remove a char from a String at its midpoint? My attempt is on Line 80 and it does not want to work.
I am using [http://java.sun.com/j2se/1.3/docs/api/java/lang/StringBuffer.html|http://java.sun.com/j2se/1.3/docs/api/java/lang/StringBuffer.html] as a reference for deleteCharAt()
Am I on the right track or should I try something else?
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import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.util.*;
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     JLabel spacer = new JLabel("");
     JButton submitButton = new JButton("Check");
     JButton clearButton = new JButton("Clear");
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          try
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          catch(Exception e)
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          Palindromes f = new Palindromes();
           f.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
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           f.setResizable(false);
           f.setVisible(true);
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          c.setLayout((new BorderLayout()));
        centerPanel.setLayout(new GridLayout(6,1));
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               centerPanel.add(enterDataLabel);
               centerPanel.add(enterDataField);
               centerPanel.add(displayLabel);
               centerPanel.add(submitButton);
               centerPanel.add(clearButton);
               submitButton.addActionListener(this);
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               c.add(centerPanel, BorderLayout.CENTER);
               addWindowListener(
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                                int answer = JOptionPane.showConfirmDialog(null, "Are you sure you want to exit?", "Palindromes", JOptionPane.YES_NO_OPTION);
                                 if (answer == JOptionPane.YES_OPTION)
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               StringBuffer firstHalf = new StringBuffer(word.substring(0,midpoint));
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          if (arg == "Clear")
               enterDataField.setText("");
               displayLabel.setText("");
}

Looce wrote:
80 |               deleteCharAt(midpoint);
82 |               StringBuffer lastHalf = new StringBuffer(word.substring(midpoint));
83 |               StringBuffer firstHalf = new StringBuffer(word.substring(0,midpoint));line numbering courtesy of GNOME's text editor(replying to self)
deleteCharAt is an instance method of StringBuffer, so you need to have one to work with. Suggestion: drop lines 82/83 and use String result = new StringBuffer(word).deleteCharAt(midpoint).toString();

Help using regex to change strings

I'm writing a utility to move sub folders from computer to computer. I am trying to get regex to work so a string like "d:\\NewScans\\22102\\7-17" would become "\\\\inv108\\data\\users\\clipper\\scan\\22102\\7-17"
so basically "d:\\NewScans\\" needs to become
"\\\\inv108\\data\\users\\clipper\\scan\\" Here is the program I wrote taht accepts the input and out put directories like:
java Paper mover d:\\NewScans \\\\inv108\\data\\users\\clipper\\scan
This is the code I wrote but it doesn't work:
/** Created to move files from a remote bureau to MPCB */
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.io.OutputStream.*;
import java.util.regex.*;
public class PaperMover{
     private File start_path;
     private File destination;
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          if(args[0] != null){
               PaperMover m = new PaperMover(args[0].trim(), args[1].trim());
               m.move_papers();
          else{
               System.out.println("no input directory");
               System.exit(0);
     public PaperMover(String path, String destination){
          start_path = new File(path);
          this.destination = new File(destination);
     public void move_papers(){
          File[] listing = start_path.listFiles();
          File temp;
          String pat = start_path.getAbsolutePath();
          Pattern P = Pattern.compile(pat);
          for(int i = 0; i<listing.length; i++){
               //get the directories IE 20123
               try{
                    if(listing.isDirectory()){
                         String t = listing[i].getAbsolutePath();
                         System.out.println(t);
                         String t2 = P.matcher(t).replaceAll(destination.getAbsolutePath());
                         System.out.println(t2);
I get string t and t2 to be equal.

I found my troubles!!

Problem with constructors and using public classes

Hi, I'm totally new to Java and I'm having a lot of problems with my program :(
I have to create constructor which creates bool's array of adequate size to create a sieve of Eratosthenes (for 2 ->n).
Then it has to create public method boolean prime(m) which returs true if the given number is prime and false if it's not prime.
And then I have to create class with main function which chooses from the given arguments the maximum and creates for it the sieve
(using the class which was created before) and returns if the arguments are prime or not.
This is what I've written but of course it's messy and it doesn't work. Can anyone help with that?
//part with a constructor
public class ESieve {
ESieve(int n) {
boolean[] isPrime = new boolean[n+1];
for (int i=2; i<=n; i++)
isPrime=true;
for(int i=2;i*i<n;i++){
if(isPrime[i]){
for(int j=i;i*j<=n;j++){
isPrime[i*j]=false;}}}
public static boolean Prime(int m)
for(int i=0; i<=m; i++)
if (isPrime[i]<2) return false;
try
m=Integer.parseInt(args[i]);
catch (NumberFormatException ex)
System.out.println(args[i] + " is not an integer");
continue;
if (isPrime[i]=true)
System.out.println (isPrime[i] + " is prime");
else
System.out.println (isPrime[i] + " is not prime");
//main
public class ESieveTest{
public static void main (String args[])
public static int max(int[] args) {
int maximum = args[0];
for (int i=1; i<args.length; i++) {
if (args[i] > maximum) {
maximum = args[i];
return maximum;
new ESieve(maximum);
for(int i=0; i<args.length; i++)
Prime(i);}

I've made changes and now my code looks like this:
public class ESieve {
ESieve(int n) {
   sieve(n);
public static boolean sieve(int n)
     boolean[] s = new boolean[n+1];
     for (int i=2; i<=n; i++)
s=true;
for(int i=2;i*i<n;i++){
if(s[i]){
for(int j=i;i*j<=n;j++){
s[i*j]=false;}}}
return s[n];}
public static boolean prime(int m)
if (m<2) return false;
boolean x = sieve(m);
if (x=true)
System.out.println (m + " is prime");
else
System.out.println (m + " is not prime");
return x;}
//main
public class ESieveTest{
public static int max(int[] args) {
int maximum = args[0];
for (int i=1; i<args.length; i++) {
if (args[i] > maximum) {
maximum = args[i];
return maximum;
public static void main (String[] args)
int n; int i, j;
for(i=0;i<=args.length;i++)
n=Integer.parseInt(args[i]);
int maximum=max(args[]);
ESieve S = new ESieve(maximum);
for(i=0; i<args.length; i++)
S.prime(i);}
It shows an error for main:
{quote} ESieveTest.java:21: '.class' expected
int maximum=max(args[]); {quote}
Any suggestions how to fix it?

Plz help using ms access as database,i want to create a login page in java

hye frnz... plz help me m new to java
m using ms access as database and try to create a login page where user type username and pw
i had enter valid user entries in database i checked connectivity is working i want as user login the main window must open after checking username and pw field to database but
now there is an error class not found exception sun:jdbc...... error
plz help me i had stuck frm 4 days */
import java.sql.DriverManager;
import java.sql.Connection;
import java.sql.Statement;
import java.sql.ResultSet;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
class Login extends JFrame
//Component Declarations
JLabel jlb1,jlb2;
     JTextField jtf1;
     JPasswordField jpf1;
     JButton jb1,jb2;
     //Constructor
     Login()
     //frame settings
          setTitle("Login Dialog");
          setLayout(new GridBagLayout());
          GridBagConstraints gbc = new GridBagConstraints();
          setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
          Dimension d= Toolkit.getDefaultToolkit().getScreenSize();
          setBounds(d.width/2-175,d.height/2-100,350,200);
          gbc.insets=new Insets(7,7,7,7);
     //adding components
          jlb1=new JLabel("User ID");
          gbc.gridx=0;
          gbc.gridy=0;
          add(jlb1,gbc);
          jlb2=new JLabel("Password");
          gbc.gridx=0;
          gbc.gridy=1;
          add(jlb2,gbc);
          jtf1=new JTextField(10);
          gbc.gridx=1;
          gbc.gridy=0;
          add(jtf1,gbc);
          jpf1=new JPasswordField(10);
          gbc.gridx=1;
          gbc.gridy=1;
          add(jpf1,gbc);
          jb1=new JButton("Login");
          gbc.gridx=0;
          gbc.gridy=2;
          add(jb1,gbc);
          jb1.addActionListener(new ActionListener()
               public void actionPerformed(ActionEvent ae)
               Connection conn=null;
                    Statement stmt=null;
                    boolean found=false;
               try
                         Class.forName("sun.jdbc.driver.JdbcOdbcDriver");
                         String dataSourceName = "Inventory";
                         String dbURL = "jdbc:odbc:" + dataSourceName;
                         conn=DriverManager.getConnection(dbURL, "","");
                         stmt=conn.createStatement();
                         ResultSet rst=stmt.executeQuery("Select * from User");
                         System.out.println(jtf1.getText()+"/t"+jpf1.getPassword());
                         while(rst.next())
                              System.out.println( rst.getString(1) +"/t"+ rst.getString(2));
          if(jtf1.getText().equals(rst.getString(1).trim()) && new String(jpf1.getPassword()).equals(rst.getString(2).trim()))
                                   found=true;
                                   rst.close();
                                   dispose();
                                   MainWindow mw= new MainWindow();     /*created min window object created to be opend after login but not working*/
                                   break;
                         rst.close();
                         stmt.close();
                         conn.close();
                    catch(ClassNotFoundException e){System.out.print(e);}
                    catch(Exception e){System.out.print(e);}
                    if(found==false) /*this portion is executing and dialog box appears invalid name and pw with class not found exception sun:jdbc.......on console */
                         JOptionPane.showMessageDialog(null,"Invalid username or password",
                              "Error Message",JOptionPane.ERROR_MESSAGE);
          jb2=new JButton("Clear");
          gbc.gridx=1;
          gbc.gridy=2;
          add(jb2,gbc);
          jb2.addActionListener(new ActionListener()
               public void actionPerformed(ActionEvent ae)
                    jtf1.setText("");
                    jpf1.setText("");
                    jtf1.requestFocus();
          setSize(350,200);
          setVisible(true);
          jtf1.requestFocus();
     public static void main(String args[])
Login l=new Login();
Edited by: 795772 on Sep 19, 2010 4:44 AM

795772 wrote:
hye frnz... plz help me m new to java
m using ms access as database and try to create a login page where user type username and pw
i had enter valid user entries in database i checked connectivity is working i want as user login the main window must open after checking username and pw field to database but
now there is an error class not found exception sun:jdbc...... error
plz help me i had stuck frm 4 days */
<snip>The subject of this forum is Oracle databases. How does your problem relate to that subject?
Two bits of advice:
1) Make sure you ask questions in a forum related to your problem.
2) If you want to be taken seriously as a professional, drop the MS IM Speak and use the language of the forum. In this forum it is English, which is successfully used by many people for whom English is far from their native language.

!! help using: public static Boolean valueOf(String s)

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