.desktop file does not show the icon in applications
I had a similar issue and I fixed it by removing a stray whitespace character at the end of the Icon line. It looks like there is whitespace in you paths, what happens if you try
[Desktop Entry]
Type=Application
Name=Oxygen_Eclipse
Comment=Eclipse Integrated Development Environment
Icon=/home/amir/IDE/OXYGEN/eclipse/icon.xpm
Exec=/home/amir/IDE/OXYGEN/eclipse/eclipse
Terminal=false
Categories=Development;IDE;Java;
StartupWMClass=Oxygen_Eclipse