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a constrain may prevent it. Provide information about the table structure as well as the data you are trying to insert.
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hi,
I am using Jdeveloper. when i make connection between Jdeveloper and MS Access it connects and i can see all my table in jdeveloper editor. but when i run my page it did not displays any thing.
Any help.
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Tufail Ahmad wrote: but when i run my page it did not displays any thing. Sorry, but we cannot guess what may be happening in your program. Please show the failing code and explain exactly what is happening.
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Tufail Ahmad wrote: Any help.
Some possibilities and there are others.
1. You are not using the connection
2. You are eating exceptions
3. You querying empty tables
4. You are not querying correctly thus no rows are returned
5. You are not populating your UI entities correctly
6. Your code isn't even running the database part so the UI part can't be populated.
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import java.util.Scanner;
public class ses
{
public static void main(String args[])
{
int i=0, n=0,p=0,j;
Scanner s=new Scanner(System.in);
p=1;
while(n!=p)
{
System.out.print("Enter a numbner");
n=s.nextInt();
if(p==1 &&n==p)
break;
for(j=2;j<=n/2;j++)
{
if(((i%j)==0)&& j!=1)
{
p=0;
break;
}
}
}
}
}
I want that program accept valeus from user until a prime number is pressed but there is a problem in that code it don`t stop after entering three or two value .
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That would be much easier to read if it were formatted consistently.
It appears that you are using p as a boolean: 1=prime , 0=non-prime So why test while(n!=p) and &&n==p ?
Also, why test && j!=1 when j will never be 1 ?
for(j=2;j<=n/2;j++) I would also test for p!=0 and remove the break
Also, you need only iterate until you reach the square root of n .
i%j It appears that i is always 0 .
I wouldn't use an if to test the division/modulo, I'd just set p
P.S. You need to reinitialize p on each loop.
modified 13-Nov-14 11:51am.
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Try:
public static void main(String args[])
boolean p = true;
int number;
int j;
Scanner s=new Scanner(System.in);
while(p) {
System.out.print("Enter a number");
number = s.nextInt();
if (number < 2)
break;
for(j = 2; j <= number / 2; j++) {
if (number % j == 0) {
break;
}
}
if (j >= number / 2) p=false;
}
}
[edit]
Modified thanks to advice by PIEBALDconsult[^].
[/edit]
modified 13-Nov-14 11:23am.
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I think the loop is supposed to terminate when the input is prime.
Testing for 1 seems needless.
Embrace if-less coding.
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PIEBALDconsult wrote: I think the loop is supposed to terminate when the input is prime. Yes, I misread the original question.
PIEBALDconsult wrote: Testing for 1 seems needless. You would think so, but some user is always going to enter a stupid value. It should really test for any number less than 2.
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Richard MacCutchan wrote: It should really test for any number less than 2.
I don't think there needs to be an extra test at all.
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I think there does. If the number entered is less than 2 then it should be ignored and the request for input repeated. So that test should really be:
if (number < 2)
continue;
not that it is earth shatteringly important.
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Here's a C# version:
bool prime ;
int number ;
do
{
System.Console.Write("Enter a number");
number = System.Int32.Parse( System.Console.ReadLine()) ;
double sqrt = System.Math.Sqrt(number) ;
prime = number > 1 ;
for(int j = 2; prime && j <= sqrt; j++)
prime = (number % j) != 0 ;
}
while(!prime) ;
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try{
String str = "select * from SUPPLIERS";
stmt = conn.prepareStatement(str);
ResultSet rs = stmt.executeQuery();
while(rs.next())
jcbSupplier.addItem(rs.getString("name"));
}catch(Exception e){
e.printStackTrace();
}
I have this code in my main program, i want to put it in other package and call it in main program,so what should i do to get the value from database and store into combobox.
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You could make it a method of another class and send the ComboBox as a reference parameter when you call it. Or it could return some collection object.
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so i just call it in main with create a ActionListener?
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Sorry, I don't understand what you mean. Please try and provide some proper detail about what you are trying to do, and what problem you are having.
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public class combobox {
private Connection conn;
private PreparedStatement stmt;
public void combobox(JComboBox jcb){
try{
String str = "select * from stocks";
stmt = conn.prepareStatement(str);
ResultSet rs = stmt.executeQuery();
while(rs.next()){
jcb.addItem(rs.getString("name"));
}
}catch(SQLException e){
e.printStackTrace();
}
}
I wrote this code in other package , and i want to call it in another package so in this package what is the code should i write to call it?
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jdzgray wrote: what is the code should i write to call it? Much the same as the code you would write to call any method of any external class. Although I don't think you should have a method with the same name as the constructor.
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I am a student working on a project that requires Iris Recognition. I write java to some extent. So please I don't know if anybody can help with the Libraries in java I can use or the way I can go about with the Iris Recognition.
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You should at least do a search for yourself to see what libraries are available and whether they offer such a feature.
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The only one I have seen is the JIIRM.jar. Which is without documentation. Also OpenCV, but don't know the way to go about it. Any one who knows how about how to go about Iris Recognition using OpenCV and java?
modified 4-Nov-14 13:24pm.
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how to open the value of one page on click of other form
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Hey guys....i have a menu with 3 image view that i set them as my buttons....now i want to when i click on each of them will going to another activity....by now....when i click on Enter button i move to the other activity and i havnt any problem with that....but i want when i clickng on About button the application inspiring me to the other activity that i created before....i dont know hot to do it?i dont know how to use this with if or else if command....can some one help me?these are the bunch of my codes....thanks :
package my.book.namespace;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageView;
public class TheLastOfUsActivity extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
ImageView myimg = (ImageView) findViewById(R.id.enter);
myimg.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View arg0) {
startActivity(new Intent(TheLastOfUsActivity.this, one.class));
}
});
}
}
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This question really belongs in the Android forum[^]. However, your question is less than clear, please try and give some more detail.
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