Connect Java Applications to Mysql Database in Ubuntu Using Netbeans IDE

Ubuntu Terminal

1. Install Mysql Server and Mysql Client from Ubuntu Software Center
2. Install JDBC Connector by typing in the terminal

   sudo apt-get install libmysql-java

3. Check if can connect to mysql by typing

   mysql -u root -p

4. Create required database and tables. For ex: create a database called newyear and table called party with fields id and name

Netbeans IDE

1. Create a Java project/application in Netbeans
2. In the main .java file add lines similar to this and save

   
   package javaapplication6;
   import java.sql.*;
   
   public class JavaApplication6 {
       
       private static final String url = "jdbc:mysql://localhost/newyear";
       private static final String user = "root";
       private static final String password = "";
           
       public static void main(String[] args) {
           System.out.println("Hello world!!");
           Statement stmt = null;
           try {
                   Connection con = DriverManager.getConnection(url, user, password);
                   System.out.println("Success");
                   stmt = con.createStatement();
                   String sql = "INSERT INTO party " + "VALUES (1, 'joe')";
                   stmt.executeUpdate(sql);
   
           } catch (Exception e) {
                   e.printStackTrace();
           }        
           
       }
   }
   

3. Then right click on the project/application in the project explorer and click on Properties
4. In the project properties window, select libraries tab. Then click on Add Jar/Folder button
5. Select mysql.jar from /usr/share/java directory and then click on Ok
6. Now save and run the project/application and check for output in the panel

Ubuntu Terminal

1. To check if the record is inserted, type:

   mysql -u root -p
   show databases;
   use newyear;
   show tables;
   select * from party;
   

Note: Just hit an enter if no password is to be set when prompted.

Install Oracle Java in Ubuntu

These steps are for installing java on a 32 bit ubuntu/linux OS.

1. Download jdk-7u10-linux-i586.tar.gz from http://www.oracle.com/technetwork/java/javase/downloads/jdk7-downloads-1880260.html
2. Download jre-7u10-linux-i586.tar.gz from http://www.oracle.com/technetwork/java/javase/downloads/jre7-downloads-1880261.html
3. The downloaded files may be stored in /home/"your_user_name"/Downloads directory
4. Remove any oracle jdk/jre binaries if any already installed

   sudo apt-get purge openjdk-\*

5. Create directory to hold Oracle Java JDK and JRE binaries

   sudo mkdir -p /usr/local/java

6. Go to the directory where the downloaded files are stored

   cd /home/"your_user_name"/Downloads

7. Copy the downloaded files into /usr/local/java and go into the directory and change the permissions

   sudo -s cp -r jdk-7u10-linux-i586.tar.gz /usr/local/java
   sudo -s cp -r jre-7u10-linux-i586.tar.gz /usr/local/java
   cd /usr/local/java
   sudo -s chmod a+x jdk-7u10-linux-i586.tar.gz
   sudo -s chmod a+x jre-7u10-linux-i586.tar.gz
   

8. Extract the compressed binaries

   sudo -s tar xvzf jdk-7u10-linux-i586.tar.gz
   sudo -s tar xvzf jre-7u10-linux-i586.tar.gz
   

9. Now the listing of the extracted files can be viewed by:

   ls -a

10. Edit the system PATH file /etc/profile and add the following system variables to the system path

    sudo gedit /etc/profile

11. Add the following lines to the end of /etc/profile file

    
    JAVA_HOME=/usr/local/java/jdk1.7.0_10
    PATH=$PATH:$HOME/bin:$JAVA_HOME/bin
    JRE_HOME=/usr/local/java/jre1.7.0_10
    PATH=$PATH:$HOME/bin:$JRE_HOME/bin
    export JAVA_HOME
    export JRE_HOME
    export PATH
    
    

12. Save the /etc/profile file and exit
13. Inform your Ubuntu Linux system where your Oracle Java JDK/JRE is located. This will tell the system that the new Oracle Java version is available for use.

    sudo update-alternatives --install "/usr/bin/java" "java" "/usr/local/java/jre1.7.0_10/bin/java" 1
    sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/local/java/jdk1.7.0_10/bin/javac" 1 
    sudo update-alternatives --install "/usr/bin/javaws" "javaws" "/usr/local/java/jre1.7.0_10/bin/javaws" 1 
    

14. Inform your Ubuntu Linux system that Oracle Java JDK/JRE must be the default Java.

    sudo update-alternatives --set java /usr/local/java/jre1.7.0_10/bin/java
    sudo update-alternatives --set javac /usr/local/java/jdk1.7.0_10/bin/javac 
    sudo update-alternatives --set javaws /usr/local/java/jre1.7.0_10/bin/javaws 
    

15. Reload your system wide PATH /etc/profile by typing the following command:

    . /etc/profile

16. Note your system-wide PATH /etc/profile file will reload after reboot of your Ubuntu Linux system
17. Test to see if Oracle Java was installed correctly on your system. Run the following commands and note the version of Java:

    java -version
    javac -version
    

ERROR 1044 (42000): Access denied for user ' '@'localhost' to database 'test'

This error may arise when running mysql from ubuntu terminal. To fix this, type:

mysql -u root -p

in the bash instead of mysql terminal.

Delete temp files in windows

1. Click on Start
2. Go to run
3. Type %temp% in the open field and click on Ok
4. Delete all the files and folders inside the Temp directory

Run PHP file from windows command line

1. Install WAMP in D drive
2. In the D://wamp/www folder create a file called test.php and enter the following and save:

   
   <!--php
   echo 'Yipee! Welcome to PHP';
   ?-->
   

3. Open the cmd (command prompt) in windows and change the directory path to: D:\wamp\bin\php\php5.4.3>
4. Now type

   php d:\wamp\www\test.php

Complile C program in Ubuntu

1. In the terminal, type:

   
   sudo apt-get install build-essential
   
   

2. Create a main directory called cprog and a sub directory called helloworld to hold the C programs

   
   mkdir -p cprog/helloworld
   
   

3. Go into that directory

   
   cd cprog/helloworld
   
   

4. Open a file called main.c in gedit editor

   
   gedit main.c
   
   

5. Type the following in main.c

   
   #include
   #include
   int main()
   {
   printf("\nHello World,\nWelcome to my first C program in Ubuntu Linux\n\n");
   return(0);
   }
   
   

6. Save and exit
7. To compile the program, go into the respective directory, as described in step3
8. Then type:

   
   gcc -Wall -W -Werror main.c -o helloworldC
   

9. To execute type:

   
   ./helloworldC
   

Install software in ubuntu using .deb file

To install software in ubuntu using .deb file, double click on it so that it links to the ubuntu software center and installs from there.

Display date time in php based on country

date_default_timezone_set('Australia/Melbourne');
$date = date('m/d/Y h:i:s a', time());
echo $date;

CKEditor custom toolbar

In the ckeditor/config.js write the following

CKEDITOR.editorConfig = function( config )
{
 config.toolbar = 'MyToolbar';
 
 config.toolbar_MyToolbar =
 [
  { name: 'document', items : [ 'NewPage','Preview' ] },
  { name: 'clipboard', items : [ 'Cut','Copy','Paste','PasteText','PasteFromWord','-','Undo','Redo' ] },
  { name: 'editing', items : [ 'Find','Replace','-','SelectAll','-','Scayt' ] },
  { name: 'insert', items : [ 'Image','Flash','Table','HorizontalRule','Smiley','SpecialChar','PageBreak'
                 ,'Iframe' ] },
                '/',
  { name: 'styles', items : [ 'Styles','Format' ] },
  { name: 'basicstyles', items : [ 'Bold','Italic','Strike','-','RemoveFormat' ] },
  { name: 'paragraph', items : [ 'NumberedList','BulletedList','-','Outdent','Indent','-','Blockquote' ] },
  { name: 'links', items : [ 'Link','Unlink','Anchor' ] },
  { name: 'tools', items : [ 'Maximize','-','About' ] }
 ];
};

Execute PHP5 script from command line in ubuntu

1. To execute a PHP script from the command line in Ubuntu you must have php5-cli installed.

sudo apt-get install php5-cli

2. After cli is installed, go to the folder where the script resides. For ex: 

cd /var/www/test
php5 index.php

Set netbeans as default editor in ubuntu

1. Install ubuntu tweak

   
   sudo apt-add-repository ppa:tualatrix/ppa
   sudo apt-get update
   sudo apt-get install ubuntu-tweak
   
   

2. Find the MIME description for your file extension
1. Right click on the file and click on properties
   
2. In the properties window, note the text shown after Type:
3. This is the mime description we are looking for. for ex: PHP script
   
3. Add a custom program to open your filetype
1. Start Ubuntu Tweak from the Dash, and click on the Admins tab on top; then click on the File Type Manager entry on the bottom:
   
2. After the File Type Manager opens, click on All in the left sidebar, and uncheck the Only show filetypes... box at the bottom:
   
3. Select any filetype on the right side, and begin typing the first few letters of the MIME description from Step 2 to automatically search and select your filetype:
   
4. Double-click on your filetype, which is now selected, to edit its associated commands.
1. Click on Add, and in the Add Application window, expand the Custom Command option on the bottom
2. Type the command/program you want or use the Browse button to navigate to it and select it; here I have selected the Netbeans editor from my /opt folder:

   
   /opt/netbeans-7.2.1/bin/netbeans
   
   

3. Click on Add, so the new command is now the default, and then click Close:
4. Now right click on file and click on properties. Click on 'open with' tab. The default application should be netbeans. Close this window and open the file. It should open in Netbeans

PHP curl installation in ubuntu

While installing magento in ubuntu there may be some errors related to php curl not being installed. To work around this, try the command:

sudo apt-get install php5-curl

Installing phpmyadmin in ubuntu

1. Open your terminal and type the command:

   sudo apt-get install phpmyadmin

2. It will ask for your password, type your ubuntu password and press enter key, it will ask for confirmation. Type

   y

   and press enter key
3. During the installation you will be prompted for a web server configuration. Select

   Apache

   and press Enter
4. Now you will be prompted for phpmyadmin configuration, select

   no

5. In terminal run the command:

   sudo cp /etc/phpmyadmin/apache.conf /etc/apache2/conf.d

6. Restart your apache server:

   sudo /etc/init.d/apache2 restart

7. Open your browser and type

   http://localhost/phpmyadmin/

8. Enter root for username and leave password field empty and click on Go
9. You will get the following error:

   Login without a password is forbidden by configuration (see AllowNoPassword)

   when trying to login to your passwordless account; 
10. To enable AllowNoPassword, uncomment or add the following line in /etc/phpmyadmin/config.inc.php :

    $cfg['Servers'][$i]['AllowNoPassword'] = TRUE;

11. To make this file editable in ubuntu, type in the terminal:

    cd /etc/phpmyadmin

    then press enter
12. Then type

    gksu nautilus

13. Make necessary changes and save the file. Now type

    http://localhost/phpmyadmin/

    in the browser and enter only the username as root and click on Go.

Reset password in ubuntu

1. Reboot into recovery mode 
2. Select Drop to root shell prompt option
3. In recent versions of Ubuntu, the filesystem is mounted as read-only, so you need to enter the follow command to get it to remount as read-write, which will allow you to make changes:  mount -rw -o remount /
4. If you have forgotten your username as well, type:  ls /home
5. To reset the password, type:  passwd username  ex: passwd meenu
6. You'll then be prompted for a new password. When you type the password you will get no visual response acknowledging your typing. Your password is still being accepted. Just type the password and hit Enter when you're done. You'll be prompted to retype the password. Do so and hit Enter again.
   Now the password should be reset. Type: exit to return to the recovery menu.
    

grub rescue problem

• Download boot repair software from http://sourceforge.net/p/boot-repair/home/Home/
• Download iso version of the software(boot-repair-disk.iso) and create a bootable usb using linux live usb creator
• Change the boot option to usb flash drive in the computer which has grub rescue problem by hitting F2 key(this is the case in lenovo laptop)
• Then insert the created bootable usb into the computer and reboot
• The boot repair software runs ... now choose the appropriate system version(32bit or 64bit)
• Then choose recommended repair and follow on screen directions
• Do a final reboot and you can see the OS loading without any grub rescue errors

Create bootable usb

To create a bootable usb from a windows 7 computer, install linux live usb creator from http://www.linuxliveusb.com/en/download
Then choose the required iso image to be extracted into the destination usb.

Posting code within editor

Integrate ckeditor with php pages

1. Download the ckeditor.zip file
2. Paste ckeditor.zip file on root directory of the site or you can paste it where the files are
3. Extract the ckeditor.zip file
4. Open the desired php page you want to integrate with ex: page1.php
5. Add some javascript first below, this is to call elements of ckeditor and styling and css without this you will only a blank textarea

<script type="text/javascript" src="ckeditor/ckeditor.js"></script>

6. Now, you need to call the work code of ckeditor on your page page1.php below is how you call it

<!--php
// Make sure you are using a correct path here.
include_once 'ckeditor/ckeditor.php';
$ckeditor = new CKEditor();
$ckeditor--->basePath = '/ckeditor/';
$ckeditor->config['filebrowserBrowseUrl'] = '/ckfinder/ckfinder.html';
$ckeditor->config['filebrowserImageBrowseUrl'] = '/ckfinder/ckfinder.html?type=Images';
$ckeditor->config['filebrowserFlashBrowseUrl'] = '/ckfinder/ckfinder.html?type=Flash';
$ckeditor->config['filebrowserUploadUrl'] = '/ckfinder/core/connector/php/connector.php?command=QuickUpload&type=Files';
$ckeditor->config['filebrowserImageUploadUrl'] = '/ckfinder/core/connector/php/connector.php?command=QuickUpload&type=Images';
$ckeditor->config['filebrowserFlashUploadUrl'] = '/ckfinder/core/connector/php/connector.php?command=QuickUpload&type=Flash';
$ckeditor->editor('CKEditor1');
?>

7. What ever name you want, you can name to it ckeditor by changing the step 6 code last line

$ckeditor->editor('mycustomname');

8. Open-up the page1.php, see it, use it, share it and Enjoy

.htaccess file redirect

// this file must exist in the current server
RewriteCond %{REQUEST_URI} etab$ [NC]

// this file or path can be in a different server
RewriteRule (.*) AM335x_eTAB.php [NC,L]

Image path setting in php for file upload

• Example: $path = realpath(dirname(__FILE__)).'/uploads/products/';
• To find server root: $_SERVER['SERVER_NAME'];
• To find server base path to current file directory: $path = $_SERVER['SERVER_NAME'].dirname($_SERVER['REQUEST_URI']);

Lenovo Laptop Screen Does Not Display

Remove battery, unplug power, hold power button for 60 seconds, turn on computer with power plug only, then shutdown, add battery and restart.

Disable autohide launcher in ubuntu 11.04

• On home tab, type compiz and click on CompizConfig Settings Manager.
• Under the category list on the left side, select Desktop and then on Ubuntu Unity Plugin on the right side.
• Set Hide Launcher to Never.

Restart apache

sudo /etc/init.d/apache2 restart

Change folder permissions in ubuntu

sudo chmod -R 777 folder_name

File permissions in ubuntu

gksu nautilus

Delete a symbolic link in ubuntu

sudo unlink filename

Drupal Custom Theme Not Detected

Generally this problem arises when the .info file is not correctly configured. Check the contents of the file and the extension of the file. It should be theme_name.info and not theme_name.info.txt or any other file extension.

Manual fix for broken image links via wysiwyg in drupal 6

While working on localhost, the path for wysiwyg images could be /sites/site_name/sites/default/files/img.jpg. But after uploading on to server, the image path could become /sites/all/default/files/img.jpg. To fix this path error manually, run the following query in the phpmyadmin sql.
UPDATE boxes SET body = replace( body, "/sites/site_name", "" )

Add external css stylesheet in drupal 6

<!--php
$inc_path = drupal_get_path('theme', 'your_theme_name') . '/path/name.css';
$file = realpath(".") ."/". $inc_path;
if(file_exists($file)) {
drupal_add_css($inc_path , 'theme', 'all', FALSE);
$vars['css']['all']['theme'][$inc_path] = 1; // this is what makes it work!
$vars['styles'] = drupal_get_css();
}
?-->

Configure wamp on windows7

One of the problems encountered during wamp installation on a windows 7 system is the following error:
"you don't have permission to access /phpmyadmin/ on this server"
This error can be rectified by changing the file content in c:\wamp\alias\phpmyadmin.conf

Before:

<Directory "c:/wamp/apps/phpmyadmin3.4.5/">
    Options Indexes FollowSymLinks MultiViews
    AllowOverride all
        Order Deny,Allow
    Deny from all
    Allow from 127.0.0.1
</Directory>

After:

<Directory "c:/wamp/apps/phpmyadmin3.4.5/">
    Options Indexes FollowSymLinks MultiViews
    AllowOverride all
        Order Deny,Allow
        Allow from all
</Directory>

Remove extra spaces in dreamweaver

• While the document is open in Dreamweaver, press CTRL+F. Do the search on the source code view.
• Check the box “Use regular expression” and uncheck any other boxes.
• Find: [\r\n]{2,}
• Replace: \n
• Click “replace all”  

Using GET Method in php

Example Code:
HTML:
<a href="?delete=id">Delete</a>

PHP:

if(isset($_GET['delete']))
{
$result = mysql_query('DELETE FROM my_table WHERE id = '.(int)$_GET['delete']);
}