Eclipse is able to recognize the compiling error of code before running, because of the JIT compiler?
None, because there isn't one. The JDT project includes a Java compiler, but a JIT would only ever be part of a Java Runtime. As download.eclipse.org points out:
You will need a Java runtime environment (JRE) to use Eclipse (Java SE 7 or greater is recommended).
Ergo, it doesn't contain one itself.