Linux Ubuntu How to add Eclipse or Other Applications to Desktop Favourite or In Desktop Grid

1. create a file name with /usr/share/applications/filename.desktop extension
2. add the exec=, icon= key value in that file.
3. give the execute permission
4. click the Grid ::: in desktop, see your added .desktop application is will show. right click and select Add to favourite. 


ex 1:

#> gedit /usr/share/applications/eclipse.desktop

[Desktop Entry]
Comment=Eclipse
Terminal=false
Name=Eclipse
Exec=/media/drvijay/Eclipse-20/eclipse
Type=Application
Icon=/media/drvijay/Eclipse-20/icon.xpm
StartupWMClass=Eclipse


ex 2:
[Desktop Entry]
Comment=mapaint
Terminal=false
Name=mspaint
Exec=wine /home/drvijay/.wine/drive_c/windows/mspaint.exe
Type=Application
Icon=/home/drvijay/.wine/drive_c/windows/mspaint.jpeg
#StartupWMClass=mspaint

#run the below cmd for execute.

#> chmod a+x ~/.local/share/applications/.desktop

Linux Ubuntu Change Complexity Length & Strong Password

vim /etc/pam.d/common-password


#Remove obscure word and add minlen=1

password    [success=1 default=ignore]  pam_unix.so minlen=1 sha512

Ubuntu Disable Each time Password Entering

sudo nano -w /etc/sudoers

Replace 

%sudo  ALL=(ALL) ALL 

TO

%sudo  ALL=(ALL) NOPASSWD:ALL

- Enjoy

Linux Ubuntu - OpenJdk Java 13 Install Setup

To uninstall OpenJDK

> sudo apt-get autoremove openjdk*

> sudo apt-get purge openjdk*

Install > 1.9 JDK 1.3

> sudo apt install -y curl

> curl -O https://download.java.net/java/GA/jdk13/5b8a42f3905b406298b72d750b6919f6/33/GPL/openjdk-13_linux-x64_bin.tar.gz

> tar xvf openjdk-13_linux-x64_bin.tar.gz

> sudo mv jdk-13 /usr/java/

> sudo nano /etc/profile
     # Go to after fi end and paste the below lines
    JAVA_HOME=/usr/java/jdk-13.0.2
    PATH=$PATH:$HOME/bin:$JAVA_HOME/bin
    export JAVA_HOME
    export JRE_HOME
    export PATH


# Configure Java Alternatives
> sudo update-alternatives --install "/usr/bin/java" "java" "/usr/java/jdk-13.0.2/bin/java" 1

# Configure Javac Alternatives
> sudo update-alternatives --install "/usr/bin/javac" "javac" "/usr/java/jdk-13.0.2/bin/javac" 1

# Check version
> java -version

# Use only in case of multiple JDKs installed

# Configure Java
> sudo update-alternatives --config java

# Configure Java Compiler
> sudo update-alternatives --config javac

>javac -version

>java version

Cassandra GUI Clien for windows - DataStax DevCenter

1. Go to Datastax Devcenter, download the latest for windows.
2. Extract it.
3. Go to bin folder and double click DevCenter.exe


4. Create Connection
5. Create KeySpace [ it is like database or schema ]
6. Create a table.
7. Use cql editor and do DML commands.