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Originally Posted by Slick Java

Hi, I am having trouble with this program. The point of this program is to roll a dice, store dice values in an array and print out how much time the value has been occurred. The output should be like this:

1 3

4 1

5 1

2 1

But I am getting this:

1 3

4 1

5 1

1 3

2 1

1 3


I am trying to find a way to get

...

Just trying to think of the topics that I want to create cheat sheets about. In the next few weeks I plan on making many more of these, here are a few topics that I think I will start with:

• Linked Lists
• Abstract Data Types
• Abstract Algorithmic Analysis
• AWT Event Handling
• Swing Components
• Swing Event Handling?
• Inheritance
• Polymorphism
• Interfaces
• Exception Handling

This is in no particular order, and I will probably be hopping around this list ...

File Input Output Cheat Sheet

Importing Libraries
The primary library that deals with files:

Java Code:

import java.io.File;

The library that deals with writing to files:

Java Code:

import java.io.PrintWriter;

FYI
If there is more then one type of information that is being transferred to or from a file, it is usually best to use a record; IMO.

Writing to a File

Declare ...

Tags: file cheat sheet, file input, file output, input cheat sheet, output cheat sheet

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Cheat Sheet

AWT Components Cheat Sheet

Importing Libraries
There are two main libraries that involve the AWT tools. This package contains the core AWT graphics classes. Contains component classes for buttons, text fields, labels, frames, panels, dialogs, and scroll panes. It also contains the layout managers such as flow layout, border layout, and grid layout. Also included are the cusrom graphics classes such as graphics, color and font.

Java Code:

import java.awt.*;

...

Updated 10-30-2012 at 06:02 AM by penguinCoder

Tags: awt, awt cheat sheet, awt component, cheat sheet

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Cheat Sheet

Importing the Library
Before you can use an ArrayList, you must first import the necessary library.

Java Code:

import java.util.ArrayList

Creating a Generic ArrayList
Generic ArrayList is an ArrayList with a type; no other type is allowed to be inserted into the ArrayList.

Java Code:

ArrayList<type> listName = new ArrayList<type>();

Example of this would be:

Java Code:

ArrayList<String> myArrayList = new ArrayList<String>();

...

Updated 10-29-2012 at 07:29 PM by penguinCoder

Tags: arraylist, arraylist cheat sheet, arraylist guide, arraylist methods, cheat sheet

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Cheat Sheet

Brief Description:
'Virtual' Memory is the mental model, or abstraction, that the programming language provides to the programmer to explain how computer memory is managed while you program is running. It is NOT the same as physical memory.

Run Time:
At run time, the operating system handles the translation from 'virtual' memory addresses to physical memory addresses, and the programmer does no need to be aware of this process.

Static Region:
This ...

Updated 10-30-2012 at 04:19 AM by penguinCoder

Tags: cheat sheet, heap, stack, static, virtual memory

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Cheat Sheet

Brief Description:
A record is pretty much just a programmer defined data type. It combines one or more pieces of information, or potentially different data types, into one unit. Structure wise, it is just a template that defines how to interpret the contents of a sequence of memory locations.

First outside of any class, define the new data type:

Java Code:

class recordName{
  public [dataType] fieldName;
  ..repeat for any number of types..
}

...

Tags: cheat sheet, how to record, record, record cheat sheet, record tutorial

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Cheat Sheet

Just for FYI, computers cannot generate actual random numbers. They are machines, and they do what they are told; and therefore cannot just choose a number at random. Mathematicians would call the process this process 'psuedo-random' number generation, but I didn't feel that made a good title so, whatever.. Just covering all the bases.

First you will have to import the library:

Java Code:

import java.util.Random;

Next, you create a random number generator; ...

Tags: cheat sheet, how to random, psuedo random, random, random number

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Cheat Sheet

The Scanner class can be used for many things other then just getting input from the user; however this cheat sheet/tutorial is just going to be about getting input from the user.

Defining the Scanner Class

Java Code:

import java.util.Scanner;

public class ClassName{
  ...code...
}

It will tell the translator to look in that directory for the code defining the Scanner class.


Declaring the Scanner
If you ...

Updated 10-18-2012 at 12:29 AM by penguinCoder

Tags: cheat sheet, input, scanner, static scanner, user input

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Cheat Sheet

A string is a piece of text, that is zero or more characters in length. In Java, strings are considered to be pre-built objects. The variable for a string does not store the value of the string, rather it is a reference point, or pointer, to the storage location of where the string is kept.


Declaring a String:

Java Code:

String s1;

Assigning a Value On Declaration:

Java Code:

String s1 = "Hello World!";

Assigning ...

Updated 10-18-2012 at 12:29 AM by penguinCoder

Tags: cheat sheet, comparing, declaring, string methods, strings

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Cheat Sheet

Class Body - the area between the braces, that contains all the code.

Constructors - used for initializing new objects

Declarations - fields that provide the state of the class and its objects

Methods - implement the behaviour of the class and its objects

Fields - member variables in a class

Local Variables - variables in a method or a block of code

Parameters - is the list of variables in a method declaration ...

Updated 10-18-2012 at 12:30 AM by penguinCoder

Tags: cheat sheet, class, keywords, method, terminology

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Cheat Sheet

Declaring a Class

Java Code:

class ClassName{
  ...code...
}

Declaring a Class with Parent

Java Code:

class ClassName extends parentClassName{
  ...code...
}

Declaring a class with Interface

Java Code:

class ClassName implements interface1, interface2, interface3{
   ...code...
}

Declaring a Class with Fields

Java Code:

class ClassName{
  public

...

Updated 10-18-2012 at 12:30 AM by penguinCoder

Tags: cheat sheet, class, constructor, examples, method

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Cheat Sheet

Well I just got out of class, and I thought I would do a brain dump of some of the terminology that is utilized in Programming and Computer Science. This is going to be in more human readable format then most places I have found on the Internet.

Abstract Algorithm Analysis

What is O(N)?
Big O of N, and it is commonly pronounced, is when the run-time of an algorithm is approximately proportional to the size of the data (N), when there are large amounts of data; in the ...

Updated 10-18-2012 at 12:30 AM by penguinCoder

Tags: instance vs class, o(n), record vs object, static vs non-static

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Cheat Sheet

how do i increase the quatity of an item when it is added again and again into my shopping cart table.there is only a button add to cart.there is no textfeild for quantitiy.
the code as of now i have retreives the items from database and add it into the shipping cart table. if i clik on it again and again the same item wil be shown again and again.

Java Code:

 DefaultTableModel model = (DefaultTableModel) 
tbl1.getModel();
            DefaultTableModel tm = (DefaultTableModel)

...

Originally Posted by .paul.

i used Dates in this particular case, as they were better suited to the application.

but i also created a java TimeSpan class, similar to the .Net Framework TimeSpan class:

Java Code:

package javaTimeSpans;

/**
 *
 * @author Paul
 */
public class TimeSpan {
    
    private int _days;
    private int _hours;
    private int _minutes;
    private int _seconds;
    
    public int Days(){

...

Hi All,
I am trying to embedd an xml response string as CData inside an XML tree. The main XML tree is not in my control to create or change. I just have a class object where i am just setting the content as String, where the string is my xml.

The problem is when the mail xml tree appears, the content of my xml ( RawProfile ) are not properly encoded.

Java Code:

<ns5:PotsdamCache xmlns:ns2="http://schemas.xmlsoap.org/ws/2002/12/secext"

...

Following diagram explains the architecture of the web servers.

Web Service Architecture

• Web Service Discovery: All the web services are discovered with the help of this part by meeting certain requirements and passing filters. The UDDI which stands for Universal Description, Discovery and Integration handles this part of web services.

• Web Service Description: All the web services are self describing which ...

Tags: architecture, web service

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Tutorial

The end and the start of the message are indicated by SOAP envelope. The receiver will be informed of the complete message arrival. When a message is received and processed, it will be informed by the SOAP envelope. So it solved the major problem of informing message processing. So in other words we can say that is a packaging method.

Following points will explain it in more detail:

• A root element is the base of SOAP envelop message and it is contained by all the

...

Tags: soap - envelope element

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Tutorial , SOAP

To exchange messages and information between multiple computers, XML based protocol is used which is called SOAP. SOAP is XML based protocol so you can say that it is the XML specification application.

Following rules or statements are considered as true for the SOAP.

• It is a protocol for communication.
• SOAP stands for Simple Object Access Protocol.
• It is designed to use internet for all its communication.
• It has the facility to use HTTP ...

Tags: soap introduction

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Tutorial , SOAP

Following are the log4j framework important support objects which are critical in this framework.

• Level Object: This object is used to define priority of log information. Following log levels are defined in the log4j API:

o INFO
o DEBUG
o ERROR
o OFF
o FATAL
o WARN
o ALL

• Filet Object: This object is used to filter and analyze the logging information. Based on the analysis and filter criteria, logging information is ...

Tags: log4j support objects

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Tutorial

Following are the log4j framework important core objects which are important and play a critical role in this framework.

• Logger Object: The Logger object is provided by the top Logger layer. All the information captured by this Logger Object is stored in a hierarchy and this is the main object responsible for collecting all information.

• Layout Object: The Layout Object is responsible for formatting all the information in multiple styles. The Layout Objects helps ...

Tags: log4j - core objects

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Tutorial

Log4J is a Java based API that provides a logging framework which is:

• Fast
• Reliable
• Flexible

The Apache software License provides the Log4J distribution. It has been also ported to following different languages:

• C++
• C
• C#
• Python
• Eiffel
• Ruby

Following are the core features and functionalities of Log4J Framework:

• It is configurable at runtime using files. ...

Tags: log4j – introduction

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Tutorial

Following are the major servlets tasks:

• The Servlet major task is to read client data that is explicitly sent. It may include:

o Data sent by a web page in form of HTML form
o Data sent by an applet
o Data sent by some HTTP client

• The Servlet major task is to read client data that is implicitly sent. It may include:

o Media types
o Cookies
o Different compression

• The servlet is responsible for data processing ...

Tags: major servlets tasks

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Tutorial

There is always a probability of programming errors in the code while a programmer is coding a JSP page. Following are the major types of errors which may arise in a JSP code:

• Checked Exceptions: The checked exception is an unforeseen error by the programmer of JSP code or it is a user error in the code. For example, you are opening a file which may not exisit or may have some issue will raise an exception. At the compile time, these checked exceptions cannot be ignored.
...

Tags: exception handling in jsp

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Tutorial

You have a website developed in JSP with different pages. The hit counter will help you the total number of users visit your any JSP page. In most cases, the hit counter is attached with “index.jsp” page. It is the main login page and most users will first visit this page before navigating to any other page on your application or website.

The following methods are used to implement hit counter. These methods are attached with you “Application” object.

• setAttribute() ...

Tags: hits counter

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Tutorial

JSP communicates with the clients using stateless HTTP protocol. For each new request, following operations are performed:

• A new connection is opened with web server.
• Server does not record client information.

In this topic, we will focus on the different ways of handling and maintaining session information. Following are the 3 main ways for session maintaining.

• Cookies: A cookies also known as session ID is assigned to a web client by the ...

Tags: jsp page, session tracking

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Tutorial

In a JSP progam, a programmer may have handled situations in which he sends information from browser to server and finally this information is communicated to backend business logic. Following two methods are used by the web browsers to send form data and information to web server.

• GET Method: The encoded information is sent from browser to the server using this GET method. The information and page URL is separated using the “?” character. Following is an example of GET method information ...

Tags: form processing in jsp

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Tutorial

The expression elements are supported by the JSP Page which:

• Are based on scripting language
• These expressions are evaluated.
• These expressions are coverted to a String format
• These are replaced with the expression elements in the JSP Page.

The expression elements in a JSP page are finally converted to a string so you can use it anywhere in your JSP Page. These expression elements must be valid and follow the Java Language. There is only ...

Tags: expressions in jsp

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Tutorial

In this topic, we will dicuss how a JSP Pages is created and processed by a web server. Following steps will explain it in more detail.

• An HTTP request is sent to the web server by your JSP Page.
• The web server is responsible for receiving this JSP Page request and it will determine that it’s a JSP request so it will call the JSP engine. This process is done for the pages that have a .jsp extension.
• The requested JSP page will be loaded from the disk and the JSP ...

Tags: jsp page processing

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Tutorial

JSP offers the following advantages as compared to using other technologies in the market.

• JSP vs Active Server Pages: The major benefit offered by the JSP as compared to Active Server Pages is that it uses Java for expression writing which is more helpful, powerful and easy to use. Where as in Active Server Pages, you will need to use Visual Basic or any other Microsoft language. The second benefit offered by the JSP is that you can port it to any other operating system.
...

Tags: advantages of jsp

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Tutorial