jde-global-classpath

1 - When in a java project i set a classpath with 
"jde-global-classpath", i'm setting the classpath for one specific 
project, or for all the projects? For example, i have project A in 
~/java/A, and i define the classpath to projectA in ~/java/A/lib. When i 
create a project B in ~/java/B, the java classes of B reach the 
classpath in project A?

2 - How can i set a classpath reachable only by the project?

Thanks,
Pedro