Don't understand at compile time and at execution time

> What does at compile/execution time exactly mean?

>

> What kind of processes are called at compile time

> (respectively at execution time)?

Execution time is also called run-time. This is when the program has been started. Compile-time is before that. The program hasn't yet been started. Compile-time isn't such a good term anymore because Java programs are compiled also while running, that is at run-time.

For Java the processes are these:

Before run-time: The Java source code is compiled to an intermediate form called bytecode.

At run-time: The JVM runs the bytecode. Earlier this was by interpretation but today the bytecode is first compiled to machine code which is run directly by the native processor.

Another way to express this is to say that a Java program is first statically compiled to bytecode and then dynamically compiled to native code at run-time. This is the same technology Microsoft is using for its .NET environment. They call it "managed code". The main advantage is that the compilation process can involve information of the actual running characteristics of the program.

uj_a at 2007-7-8 0:59:12 >