I have to burn a java-application on a cd. This application have to run on every windows pc wihtout any installation (also jre shouldn't be installed) before.
I am actually new to java programming and am finding it difficult to take integer input and storing it in variables...i would like it if someone could tell me how to do it or provide with an example like adding two numbers given by the user..
Learning just another language is not much work. However, getting familiar with all the supporting libraries is veeeery expensive and actually you cannot go too far without that.
Would you consider a worthy career investment to learn java once you already are an accepted professional of .NET or you would rather invest the same amount of energy to get deeper in the things you already know?
If I wanted a single word that meant "conforming to Java language conventions", what would that be? Python has the term "pythonic". Would it be "javaish"?
Any tips or best practices for unit testing Google Wave robots written in Java? I'm expecting to deploy on AppEngine, if that helps. I'm a fan of TDD but new to both Wave Robots and AppEngine, so I'm hoping to use TDD to help me explore the design space.
Basically I want to be able to encrypt and decrypt with AES 256. What is the industry standard library for encryption in Java? Something that has been around a long time and is tried and true.
Hello,
I'm creating a java web application runing on a Tomcat server.
One of the functions fill in a StringBuffer variable with data.
At the end, I would like to propose the user to download the generated content packaged in a text file. This without having to store the file on the server.
I've been searching for a code snippet but couldn't find anything corresponding ...
I hope I've been clear enough on my problem.
Thanks in advance,
I want to make Java JDialog appear like it is presented in the [Image][1]
[1]: http://lh4.ggpht.com/_AnzmYq61hHI/S8RTAznktKI/AAAAAAAAAW0/c4HVCuchdjc/s1600-h/saveConfiguration%5B2%5D.jpg using JDK 6 Swing. Is it possible? if so kindly guide me.
Image Link
Hi,
After some serious googleing I found out that the RandomAccessFile-class is not thread-safe. Now I could use one semaphore to lock all reads and writes but I don't think that performs very well. In theory it should be possible to do multiple reads and one write at a time.
How can I do this in Java? Is it possible at all?
Thanks!
I haven't found many ways to increase the performance of a Java application that does intensive XML processing other than to leverage hardware such as Tarari or Datapower. Does anyone know of any open source ways to accelerate XML parsing?
This question showed up on my mid-term exams and I've been searching for correct answer for some time. I know that Java interfaces can't be directly instantiated so they don't need constructors and that they can have only public static final attributes so they don't need constructors to set them up but that's not the expected answer.
I need to use a few Cyrillic characters in a Java file and in order for Eclipse to allow me to do so I need to change the encoding for that file (currently to UTF-8).
Are there any possible problems that this could cause?
How to/What is a good library, to create a fading indicator message in Java like that of Outlook when you get a message, or Ubuntu/Gnome when you've connected to a network?
What's the easiest way to create a simple HTTP server with Java? Are there any libraries in commons to facilitate this? I only need to respond to GET/POST, and I can't use an application server.
What's the easiest way to accomplish this?
Hi,
I'm a beginner in java. I want the logic of the small program.
I have two arrays
array = {a1,a2,a3,a4,a5,,,,,,,,,an}
and
array2 = {b1,b2,b3,b4,,,,,,,,,,,bn}
I want string as:
a1b1,a2a3b2b3,a4a5a6b4b5b6,..........an
Please tell me what will be the logic.
I want to make a java application software which give the current status/information of the running computer. So, for this, is there any inbuilt/extrnal library present or not?
Can anyone give a simple code which will just. "What is the current status of laptop battery?" or "Is AC adapter is pluged in or not?"
Please help me.
I have a .net application which needs to expose a service consumed by a java client. The service can't be public. There should be some authentication mechanism for the client. What is the best way to do this? I'm new to web services and am confused by all the soap, wsdl etc. and have also heard a lot that it'll be a pain to get the two to communicate. Your thoughts?
What is the best procedure for storing and retrieving, using native Java serialization, generic objects like ArrayList<String>?
Edit: To clarify. When I serialize an object of type ArrayList<String> I'd like to de-serialize to the same type of object. However, I know of no way to cast back to this generic object without causing warnings.
Hi there,
is it possible to access a shadowed field of an enclosing class from the enclosed one in Java?
public class Inherit {
public int a = 3;
private int b = 5;
public class Inheriting {
public int a = 23;
private int d = 8;
public void f() {
System.out.println("Here I want to get a = 3");
...
}
}
}
Cheers!
I'm using a MySQL database and accessing it through Java.
PreparedStatement prep1 = this.connection.prepareStatement("UPDATE user_table
SET Level = 'Super'
WHERE Username = ?");
prep1.setString(1, username);
The update statement above works fine however I'd like to get the number of rows affected with this statement. Is this possible please?
Hi,
After I read Bloch's discussion http://www.infoq.com/news/2010/04/bloch_java_future
I started to think about "Do I have to switch to scala for new web developements" or is java preferred in all cases. What is your opinion ?
Thanks,
This is simply for fun. This will not be used for any actual encryption. I'm only first year comp sci student and love cryptography.
This took a long time to get working. At approximately N = 18, it begins breaking down. It won't encrypt messages properly after that point. I'm not sure why. Any insights? I'd also appreciate any links you could provide me to tutorials or interesting reading about Cryptography.
import java.math.BigInteger;
import java.security.SecureRandom;
/**
* Cryptography.
*
* Generates public and private keys used in encryption and
* decryption
*
*/
public class RSA
{
private final static BigInteger one = new BigInteger("1");
private final static SecureRandom random = new SecureRandom();
// prime numbers
private BigInteger p;
private BigInteger q;
// modulus
private BigInteger n;
// totient
private BigInteger t;
// public key
private BigInteger e;
// private key
private BigInteger d;
private String cipherText;
/**
* Constructor for objects of class RSA
*/
public RSA(int N)
{
p = BigInteger.probablePrime(N/2, random);
q = BigInteger.probablePrime(N/2, random);
// initialising modulus
n = p.multiply(q);
// initialising t by euclid's totient function (p-1)(q-1)
t = (p.subtract(one)).multiply(q.subtract(one));
// initialising public key ~ 65537 is common public key
e = new BigInteger("65537");
}
public int generatePrivateKey()
{
d = e.modInverse(t);
return d.intValue();
}
public String encrypt(String plainText)
{
String encrypted = "";
int j = 0;
for(int i = 0; i < plainText.length(); i++){
char m = plainText.charAt(i);
BigInteger bi1 = BigInteger.valueOf(m);
BigInteger bi2 = bi1.modPow(e, n);
j = bi2.intValue();
m = (char) j;
encrypted += m;
}
cipherText = encrypted;
return encrypted;
}
public String decrypt()
{
String decrypted = "";
int j = 0;
for(int i = 0; i < cipherText.length(); i++){
char c = cipherText.charAt(i);
BigInteger bi1 = BigInteger.valueOf(c);
BigInteger bi2 = bi1.modPow(d, n);
j = bi2.intValue();
c = (char) j;
decrypted += c;
}
return decrypted;
}
}