Dusk vs Dawn. Dusk and dawn are actually opposite times of the day. The former refers to the time before night starts while the latter refers to the time just before the night ends. There is no specific time for them, however, as sunrise and sunset occurs differently everyday. Dusk.
What is JMS? Java Message Service (JMS) is an application program interface (API) from Sun Microsystems that supports the messaging communication between computers / applications / software components in a network.
The Java Virtual machine (JVM) is the virtual machine that run the Java bytecodes. The JVM doesn't understand Java typo, that's why you compile your *.java files to obtain *.class files that contain the bytecodes understandable by the JVM.