Conexion de una base de datos de PostgreSql 8.2 a Java

A simple algorithm to convert decimal numbers to binary; pointless since most languages have an inbuilt function but was used for learning about algorithm design.

The decrypter for the simple encrypter I posted earlier - Takes the encrypted text from a text file - "encrypt.txt" which the encrypter automatically writes to.

A quick implementation of an encrypter which can't be cracked by frequency analysis.

Search file directory (recursive method) with java language

Convert InputStream to byte[]

Convert java.awt.Canvas to java.awt.image.BufferedImage

Determine if a graph is bipartite.

Ordenate array with a queue.

Ackermann recursive.

View swatch time in c++

Snippet for display one frame in full screen mode.

From a tutorial on building an RSS SAX parser on my website:

full article can be found here

Convert
java.awt.Canvas to java.awt.image.BufferedImage or java.awt.image.Image

Shows a few objects I built to perform some screen scraping...

I like to have these two methods in my toolbelt, even though it's syntactic sugar, I think it aids clarity.

A GroovyClassLoader demonstration. The given domain is a german water flow meter system; I think, you shouldn't be able to understand the domain, but you should be able to understand, how to load a Groovy class in Java via a GroovyClassLoader.

It is a simple converter which converts your number into roman number.
Due to roman numbers it can converts 4 digits.

I'm in the process of writing test fixtures for our rails site. A lot of my tests require authentication, so I've had to port our permissions system into a fixture. Rather than type out all of the information for the fixture, I decided to create a nested loop that will take care of this for me.

There's probably a rake task for this, but I wasn't able to find it, so I came up with my own solution. You'll have to do a little cleanup when it's done, however some slight mods to this loop could even eliminate that.

This little number will allow the contents of other pages to be included or embedded into the rendered HTML of an aspx page. Using the WebClient class from the .NET framework, you can conditionally load pages, even manipulate the HTML before it is rendered and in this example, fill in forms and execute javascript actions.

The following example shows how to auto-login to an Exchange Server - this was something requested for inclusion into our portal, but I left out the logic that pulls/decrypts the real password - for obvious reasons.

Enjoy!
~Jeremy

Gives factorials for a given value.

This is a very convenient way to remove all doubles from a List in Java. The only prerequisite is that the elements in the list have proper equals and hashCode methods.

It work by using the constructor of a Set that takes a Collection as an argument.

I poured the snippet in a little program so can run it straight away.

Adds any character at the given index of a string.

NOTE: Count starts from 0

This simple function simply removes the character at the given index from a string.

NOTE: The count starts from 0

create a random string of 16 chars

IP2Location is a Ruby library that enables the user to find the country, region, city, coordinates, zip code, ISP and domain name that any IP address or hostname originates from. It has been optimized for speed and memory utilization. Developers can use the API to query all IP2Location™ binary databases for applications written in C or supporting static/dynamic library.

Function that splits a given string into sections based on the allowed length for a section. Does not split words up. Splits string on Space character (can be set to another character)

To create a chatprogram in java we need 2 classes one for Client and one for Server from which the client will be able to connect and exchange text messages. to compile the code simply type these commands in command prompt window:-
1)ipconfig(memorize the Ip address)
2)javac client.java
3)javac server.java
4)java server 10.69.23.203 (You need to type your own ip address)
5) After this you need to open another command prompt window(Make sure the server command prompt window is also open). now type:
java client 10.69.23.203
Thats it.
if anyone have any problems please post a comment and i will answer all of your questions or if you are having trouble in compiling.

This snippet illustrates using Genetic Algorithm for the hardware optimization.

Genetic Algorithm implementation.

See also "Weighted random selection" for RandomItemSelector class source.

Weighted random selection from the list.

Don't forget to call itemsChanged after updating list content.

This snippet illustrates following:

1. Using http request to get the data
2. Parsing RSS feeds
3. Sending email

This code illustrates using ruby REXML package. It converts J2EE web application deployment descriptor web.xml into Freemind mindmap document.

This class illustrates mixed GUI/command line parameters passing. Any parameter may be specified in the command line. All unspecified parameters will be read using GUI dialog box.

Customizable recursive directory scanner.

Configurable number formatter.

Implementation-independent XML builder.

This class uses reflection to locate option setters. Client class must contains methods setFile (to receive file names from the command line) and setOption### (to receive option ###).

(See also adapter-based implementation)

Based on "Random Password Generation"

Simple C++ program that creates a directory with the asked username, and places 2 files within the directory that contain the asked for username and the asked for password.

This is an edit of another snippet I made, but I have fixed the creation of the user's folder so it is named after the user.

FlyingIsFun1217

What is Dijkstra Algorithm? click on the link above and first understand what the algorithm is all about. in short it calculates the shortest path from A to F or vise versa. This code i can guarantee is the simplest and easiest code to understand. just search on google and try to compare this code and other dijkstra code and you will see what i am talking about. i spent alot of time myself and my instructor to guide me on the rite path.
http://en.wikipedia.org/wiki/Dijkstra%27s_algorithm(Description)
to see how the algorithm really works go on this website it tells you step by step how to update the cost and which path to choose.
http://renaud.waldura.com/doc/java/dijkstra/
Please give some time to understand the algorithm first and then you can see my code. if you done understand the algorithm it is very useless. i know alot of people need Dijkstra algorithm in java for their HW assignment or Test. i am giving you the solution step by step. anyone who wants to understand please go to the url i have posted above and once you have understand then run the code and for those people who just want to copy so that they can get 90% in their test No Problem Here it is .
First open a notepad and name that file anything like data.txt or datas.txt and make sure the file looks something like this and in this format.
0 3 100 5 100 100 (100 represents infinity)
3 0 6 7 7 100
100 6 0 5 5 3
5 7 5 0 1 100
100 7 5 1 0 2
100 100 3 100 2 0
i name this file as a data.txt file. i have 6 nodes. and A is always the starting node which has the cost of 0 so by looking at the first line i
know that A to A have distance 0, A to B is 3, A to c is Infinity, A to D is 5, A to E is Infinity(means no edge connected with A), A to F is Infinity.
for second line(B to A is 3, and then vise versa) and for the 3rd line it starts for C and etc..
save the txt file by any name and then copy the code which i have posted and then to run type this:
javac routing.java
java routing data.txt
you will get the output. i will say this one more time understand how the algorithm works or ......................

I was looking for an easy way to populate a combo box with strings taken from an enumeration, and also to be able to pull out Enum objects from the combo box. After some searching, I found EnumComboBoxModel on the JDesktop website, but was not able to find any code.

Instead I came up with an easier solution that did not require me to define a new Model class, but instead uses javax.swing.DefaultComboBoxModel.

Sorry for the disorganization of the code, but hopefully you get the idea.

Using the Termios library, we can have the user enter a character on the keyboard, without it being displayed on the screen.

When doing a lot of testing in script/console, you often have to reload to pickup changes in DB schema, models and libs. The process of quitting the console and restarting it can become incredibly tedious amidst bugtracking.

note: I don't believe this reloads items in the libs dir

From time to time you may have reasons to override the default find method that ActiveRecord provides. In this example, we'll store a side-copy of the record attributes so that we have some basis for discovering changes to the data.

note: this will not override dynamic finders such as find_by_id

Two very usefull functions to have around.

(note: dollarfy requires commify to work)

This function returns a Date object being set at 12 A.M. It is useful for comparing dates where you don't know if they'll come set at the beginning of the day or not.

Classe que pren una frase i una clau i obté com a sortida el missatge encriptat usant l'algorisme de Vigenère.

Classe que donada una frase té com a sortida la mateixa frase però havent-li aplicat la xifra del cèsar (per defecte amb valor 3).

It’s difficult to find OpenSSL for windows, especially for 64 bit Windows.

after doing some googling, I decideded to providing a simple installation of OpenSSL for windows by myself. It’s easy to use . No need to compile anything....

read more....

Convert Unicode To UTF8

I was coding a project that used arrays when the lack of a standard foreach in C/C++ got to me. So, I coded this little function to help me. It applies a function that returns int to each element of the array.

I made this a little while back for a friend who was having trouble learning sockets. Below are snf.h, snferror.h and example.cpp (a little example).

The example opens a "web server" at port 8080 on the machine. However, it displays just one page.

Have fun!

This little function puts a string of a specified color and (centered) location. However, keep the word simple in mind. I purposfully not made it capable of supporting newlines.

By the way, this is my first snippet

I use this function when passing an array to a function being called from setTimeout();

Add this header after all your other headers. Compiles on standards compliant compilers.

Similar to Perl's CGI::escapeHTML(), though (because we can!) this adds it as a method to all String objects.

Nifty way to swap two integers in C (C++) without using a temporary variable. Uses one line of code (3 assignments).

Turns any string backwards. If you input "Test" it gives out "tseT". Hope it's useful.

The snippet shows how to use it.

The modus operandi for this is similar to that taken by PHP's implementation of such functions. It's comparitively memory-intensive, but is much faster than running a whole bunch of tests.

Basically, you set a mask -- an array of 256 null bytes -- and set those that correspond to characters you wish to trim. Then, rather than having to test if a character is in the set of characters to trim(O(n), or linear time on *ws), you just test once (O(1), or unit time) to see if the byte in question is set.

And of course, to trim(), you just wrap trim() around both ltrim() and rtrim().

One point of caution: these functions trim in place, so copy strings before trimming them. (Of course, if you usually want access to both pre- and post-trimmed strings, you could always make these malloc() a new string and return a pointer to it . . . )

Another pull from my growing-towards-beta CGI library: sgcgi_url_unescape().

Note the use strcpy, which is faster than the equivalent memmove()ing. To ensure 64-bit safety, I plan to rename this function and then conditionally compile it to point to either strcpy or a 64-bit-safe memmove() implementation of strcpy.

However, even though copy order isn't guaranteed for strcpy, on 16-bit and 32-bit systems, all known implementations copy byte-by-byte from lower addresses to higher addresses. Some 64-bit optimized compilers may copy 8-byte chunks, making the assumption of full linearity unstable at best.

I know it sounds like I'm justifying use of nonstandard code for convenience . . . *blush* . . . it's just something that putting in a -DPEDANTIC type of preprocessor flag could fix if broken, and its SO much faster!

The best way I've found to keep a suite of CGI environment variables in my C CGI programs is actually just to read them as name-value pairs into a stack. It simplifies parsing and makes the code cleaner and less fragile than using a specialized structure or an ordered array of strings (as well, empty variables are simply not push()ed onto the stack, so memory doesn't have to be allocated for empty strings). Plus, since there are never a huge number of environment variables, and they are all unique (by definition), a search through the stack for a given name takes minimal time. In fact, retrieval of environment variables beats a PHP-like hash-table implementation by a good deal.

In the code below, all you have to keep in mind is that the NVStk is a name/value pair stack (implemented as a singly-linked list with each node containing two char*s). Variable retrieval times can be minimized by adjusting the order of variable names in the char**s passed to sgcgi_getenv(). In fact, the ones below are just about backwards from how they ought to be, since I forgot I was using a stack instead of a queue . . . *blush*

Of course, there are more environment variables you can get, but you have to draw the line between exhaustion and efficiency, and that depends on the project. The variables included here are pretty much overkill for any program you're likely to need.

A nice way to use these types of functions is to wrap them in an accessor function that gets the environment once and keeps it as a static variable, and then on subsequent calls just looks up values in its stack. (If you want to see the NVStk, I can put it up, but it's pretty much a basic linked list.)

Generates an 88 character secure hash string for the passed in strings.

A simple tool used for fast Exponentiation. Very useful if you are creating your own cryptograpgic methods.

A simple tool used for fast Exponentiation. Very useful if you are creating your own cryptograpgic methods.

This function loads an File into an String.

This function provides the reverse of a string. It is constructed using string builder because strings in .NET are immutable, while stringbuilders are not. Therefore large strings could be slow to reverse if a regular string was used for the working value that is returned.