I am very new to programming, so please bear with me, and apologies in advance if at first I dont make sense...!
I am doing an undergrad programming project, and need to make some databases within a Java program. I am using eclipse (galilo) to write my program. I have downloaded a connector/J, but havent the foggiest how i should use it!
Anyone out there able to give me a step by step approach?!
Many thanks!
I am currently picking up Grails and Roo to expand my skills and to have a bit of fun.
The vast majority of training materials appear aimed at new developers or Java developers.
Does anyone know of any guides, resources or have any tips and anecdotes for translating existing development experience with .Net (C#/ASP.Net/Asp.Net MVC)?
How can I parse a strings like :
name1="val1" name2="val2" name3="val3"
I cannot use split(\s+) as it can be name = "val 1".
I am doing java but any laguage is okay.
I believe conversion exactly to BigInteger[] would be optimal in my case. Anyone had done or found this written in Java and willing to share?
So imagine I have arbitrary size byte[] = {0xff,0x3e,0x12,0x45,0x1d,0x11,0x2a,0x80,0x81,0x45,0x1d,0x11,0x2a,0x80,0x81}
How do I convert it to array of BigInteger's and then be able to recover it back the original byte array safely?
ty in advance.
Hello,
I made a Java application which I would like to distribute on Windows, OSX and Linux without distributing a jar file. I used the great Windows exe wrapper http://launch4j.sourceforge.net/ to create an .exe file complete with my icon that won't scare Windows users.
Are there similar wrappers that I can use for OSX/Unix? An important consideration is that I would like to have my own icon on the executable (especially for mac users).
Thanks!
I create java Media player and finished Video player, Audio Player, taking snapshot, etc., But i can only capture the video using webcam. I want to record the video in hard disk. What I have to do for that..?
Thanks in Advance.
For this Java code:
String var;
clazz.doSomething(var);
Why does the compiler report this error:
Variable 'var' might not have been initialized
I thought all variables or references were initialized to null. Why do you need to do:
String var = null;
??
I have created a Java application (project) in NetBeans, in which I have designed a JFrame with menu bar, and different JPanels. I want these JPanels to appear inside the JFrame on action of different menu items, so that whenever the menu items are clicked different JPanels should appear inside the JFrame. I have designed both JFrame & JPanel separately, but I couldn't link them together.
Please help me out friends.
Can you please tell me how does this java code work? :
public class Main {
public static void main (String[] args) {
Strangemethod(5);
}
public static void Strangemethod(int len) {
while(len > 1){
System.out.println(len-1);
Strangemethod(len - 1);
}
}
}
I tried to debug it and follow the code step by step but I didn't understand it.
I have an instance of Tomcat 6.0.18 running on Sun's Java HotSpot(TM) Server VM build 1.6.0_14-b08. Is there any way for me to find out what garbage collection algorithm the JVM is using to run my web application?
Hi.
how can I have a field with variable type in my class? I use hibernate annotation for mapping to DB. I tried to use java.io.Serializable as field's type, but it mapped to database as a 01 amount which is true if I get it's object and cast it to it's true type. but I need to run a query on this objects that needs true amount of field.(right now I can't compare an integer field with a number)
Does anyone have any idea how can I do this?
Thanks in advance.
I can't seem to find any example of how to do this. Imperatively in java it would be a piece of cake of course, but I can't seem to figure out how to inject my JaasVerifier into my SpringComponent declaratively from within the xml.
It appears from the method signatures that Verifier is designed to be attached to Context, but the instance of Context itself is created as a side effect of the SpringComponent creation so I can't get a hold of it in Spring. There must be something I am missing.
I try to play with sockets a bit. For that I wrote very simple "client" and "server" applications.
Client:
import java.net.*;
public class client {
public static void main(String[] args) throws Exception {
InetAddress localhost = InetAddress.getLocalHost();
System.out.println("before");
Socket clientSideSocket = null;
try {
clientSideSocket = new Socket(localhost,12345,localhost,54321);
} catch (ConnectException e) {
System.out.println("Connection Refused");
}
System.out.println("after");
if (clientSideSocket != null) {
clientSideSocket.close();
}
}
}
Server:
import java.net.*;
public class server {
public static void main(String[] args) throws Exception {
ServerSocket listener = new ServerSocket(12345);
while (true) {
Socket serverSideSocket = listener.accept();
System.out.println("A client-request is accepted.");
}
}
}
And I found a behavior that I cannot explain:
I start a server, than I start a client. Connection is successfully established (client stops running and server is running). Then I close the server and start it again in a second. After that I start a client and it writes "Connection Refused". It seems to me that the server "remember" the old connection and does not want to open the second connection twice. But I do not understand how it is possible. Because I killed the previous server and started a new one!
I do not start the server immediately after the previous one was killed (I wait like 20 seconds). In this case the server "forget" the socket from the previous server and accepts the request from the client.
I start the server and then I start the client. Connection is established (server writes: "A client-request is accepted"). Then I wait a minute and start the client again. And server (which was running the whole time) accept the request again! Why? The server should not accept the request from the same client-IP and client-port but it does!
I'm trying to use XMLTask 1.16, but, unfortunately, I got error,
java.lang.UnsupportedClassVersionError: Bad version number in .class file, all the time. But if I switch back to XMLTask 1.15, it work fine. Does anyone know how to make XMLTask 1.16 work with Ant.
Hi,
I need huffman code(best in python or in java), which could encode text not by one character (a = 10, b = 11), but by two (ab = 11, ag = 10). Is it possible and if yes, where could i find it, maybe it's somewhere in the internet and i just can'd find it?
JFace Databinding doesn't support generics, so it isn't particularly type-safe. And apparently it never will, since they wish to preserve Java 1.3 support.
JGoodies supports generics since 2.0.0. Has anyone ported JGoodies 2 to SWT/JFace? Or is there another library which allows both?
Hi,
Is there an elegant way in Java to code:
if (10 < x < 20) {
...
}
i.e. "if x is between 10 and 20"
rather than having to write
if ((x > 10) && (x < 20)) {
...
}
Thanks!
In the below example,
class ex8
{
public void show()
{
try
{ int a=10/0; return;}
catch(ArithmeticException e)
{ System.out.println(e); return ;}
finally
{ System.out.println("Finally"); }
}
public static void main(String[] args)
{
new ex8().show();
}
}
the output is:
java.lang.ArithmeticException: / by zero
Finally
How is it that Finally gets printed in spite of return statement in catch?
Hi,
Is it possible to generate word documents (*.doc) in java web application using Eclipse BIRT (Report Engine)? I want .rptdesign to be an input file in generating process. I could not find any example or tutorial.
What would you recommend as an alternative solution. As far as I know Jasper Reports allow only RTF format generation.
Thank you for your answer/explaination
Hello,
My company wants to use Liferay for developing a portal and integrate Alfresco with it for document management.
But both Liferay and Alfresco are Java based and i would like to know if there are any alternatives to Liferay and Alfresco in PHP or Python.
Thank You
I would like to design a PvP game uses flash in client and java socket server, but I do need server validates trajectory and if bullets hit target from cheating.
Is there any tutorial or paper provides how to do this ?
what's are the uses of the host param with java applets?
can it be tricked to use a different server than the originating server?
I didn't find a clear complete explanation of the host param.
Im getting classnotfountexception on Class.forname("com.mysql.jdbc.Driver")
im using:
windows vista 64-bit,
Eclipse Galileo,
GWT framework
i downloaded (mysql-connector-java-5.1.6-bin), but what the exact path i should add to.
im getting this exception while im in gwt-projects, but normal projects working good,
any idea how that should be done???...thanks
I've written the following if-statement in Java:
if(methodName.equals("set" + this.name) ||
isBoolean() ? methodName.equals("is" + this.name) :
methodName.equals("get" + this.name)) {
...
}
Is this a good practice to write such expressions in if, to separate state from condition? And can this expression be simplified?