I have many Projects configured inside Eclipse IDE .
When i run a Simple Java File , by taking a new project (Closing other Projects) , it takes a lot of time
for launching , it displays as "Building workspace to complete "
Is it not possible to eliminate all these Operations as "Building workspace to complete " to make run a simple java file
You can turn off automatic builds via the option in the Project menu. However, you need you IDE to build your code, otherwise why bother using one? If a simple application is slow (and you have tried tuning your environment) I would look to invest in a higher specification PC.
I assume that you have a lot of projects in your one workspace. A better solution might be to have multiple workspaces. I have three primary workspaces and will often create another workspace for specific projects. This way I don't have the overhead of making Eclipse examine projects that I am not interested in at the time. I make liberal use of the export/import preferences capability to ensure that all of my workspaces are configured the same.