JAVA QUESTIONS HELP!!!!!

Question

Hi there im a student and have an exam on java coming up next week, i have a few past paper questions that im stuck with if anyone can help that would be great.....
1.) Java implements generic types by erasure: what does this mean?
A. The compiler removes references to parameter types and inserts casts wherever return types refer to parameter types.
B. The programmer must comment out references to parameter types before code is compiled.
C. The compiler removes any casts that may be type-unsafe. 􀀀
D. The compiler removes any references to parameter types and inserts references to the closest super class that will make expressions type-safe.
E. Any type-unsafe casts to parameter types will be ignored by the interpreter at run-time.
2.) In Remote method Invocation, what is meant by �marshalling�?
A. Marshalling is the process of synchronizing all parameters to the method being invoked, in order to
prevent data corruption arising from the concurrent method call. 􀀀
B. Marshalling is the process of sending a copy of the remote object to the client JVM in order to
invoke its method locally. 􀀀
C. Marshalling is the process of sending the state of the client JVM on a byte stream to the remote
object in order that the JVM can be started as a separate thread on the remote host. 􀀀
D. Marshalling is the process of suspending the current thread in the client JVM until a result is obtained
from the remote method invocation. 􀀀
E. Marshalling is the process of sending the state of all parameter instances on a byte stream to the remote object.
3.)What is the immediate superclass of javax.swing.JFrame?
A. java.lang.Object 􀀀
B. javax.swing.Window 􀀀
C. javax.swing.JComponent 􀀀
D. java.AWT.Window 􀀀
E. java.AWT.Frame
4.) What is the immediate superclass of javax.swing.JComponent?
A. java.lang.Object 􀀀
B. java.AWT.Component 􀀀
C. java.AWT.Container 􀀀
D. java.AWT.Window 􀀀
E. javax.swing.Object
5.) Which of the following statements about the java.AWT and javax.swing packages is true?
A. All components in both packages are thread-safe􀀀
B. Most components in both packages are thread-safe􀀀
C. Most components in java.AWT are thread-safe, but most in javax.swing are not􀀀
D. Most components in javax.swing are thread-safe, but most in java.AWT are not􀀀
E. No components in either package are thread-safe􀀀
6.) Which of the following best describes how AWT events are handled in Java?
A. There is a special thread that handles all AWT events. 􀀀
B. Each AWT event causes a new thread to be created to handle that event. 􀀀
C. All AWT events are handled in the main thread. 􀀀
D. The programmer must explicitly create one thread to handle all AWT events. 􀀀
E. For each AWT event, the programmer must explicitly create a thread to handle that event. 􀀀
7.) Which of the following best describes how component-generated events can be handled in Java?
A. All component-generated events are handled automatically by the Java interpreter. 􀀀
B. The programmer creates instances of appropriate listener classes, and registers these instances with
the component; when the component generates an event, the relevant methods of all registered
listeners are executed. 􀀀
C. The programmer creates instances of appropriate listener classes, and registers these instances with
the component; when the component generates an event, one of the registered listeners is chosen by
the interpreter and the relevant method of that instance is executed. 􀀀
D. The programmer must declare a subclass of the component and add one method for each type of
event the component can generate; when the component generates an event, the appropriate method
is executed. 􀀀
E. Each component class has event-handling methods; the programmer declares a subclass of the
component and overrides those methods; when the component generates an event, the overridden
method is executed. 􀀀
Any help would b great thanks guys. Andy

Answer 1

1.) Java implements generic types by erasure: what
does this mean?
A. The compiler removes references to parameter types
and inserts casts wherever return types refer to
parameter types.
B. The programmer must comment out references to
parameter types before code is compiled.
C. The compiler removes any casts that may be
type-unsafe. 􀀀
D. The compiler removes any references to parameter
types and inserts references to the closest super
class that will make expressions type-safe.
E. Any type-unsafe casts to parameter types will be
ignored by the interpreter at run-time.None of the above (assuming this is not a Google translation of some non-English text).
2.) In Remote method Invocation, what is meant by
�marshalling�?
A. Marshalling is the process of synchronizing all
parameters to the method being invoked, in order to
prevent data corruption arising from the concurrent
method call. 􀀀
B. Marshalling is the process of sending a copy of
the remote object to the client JVM in order to
invoke its method locally. 􀀀
C. Marshalling is the process of sending the state of
the client JVM on a byte stream to the remote
object in order that the JVM can be started as a
separate thread on the remote host. 􀀀
D. Marshalling is the process of suspending the
current thread in the client JVM until a result is
obtained
from the remote method invocation. 􀀀
E. Marshalling is the process of sending the state of
all parameter instances on a byte stream to the
remote object.None of the above. Although there is one answer that at least describes how Marshalling is used.
3.)What is the immediate superclass of
javax.swing.JFrame?
A. java.lang.Object 􀀀
B. javax.swing.Window 􀀀
C. javax.swing.JComponent 􀀀
D. java.AWT.Window 􀀀
E. java.AWT.FrameAt least this one does have the correct answer. It's in the API docs, so I guess it'd be hard to be wrong.
4.) What is the immediate superclass ofDitto.
5.) Which of the following statements about the
java.AWT and javax.swing packages is true?
A. All components in both packages are
thread-safe􀀀
B. Most components in both packages are
thread-safe􀀀
C. Most components in java.AWT are thread-safe, but
most in javax.swing are not􀀀
D. Most components in javax.swing are thread-safe,
but most in java.AWT are not􀀀
E. No components in either package are
thread-safe􀀀Again, none of the above.
6.) Which of the following best describes how AWT
events are handled in Java?
A. There is a special thread that handles all AWT
events. 􀀀
B. Each AWT event causes a new thread to be created
to handle that event. 􀀀
C. All AWT events are handled in the main thread.
􀀀
D. The programmer must explicitly create one thread
to handle all AWT events. 􀀀
E. For each AWT event, the programmer must explicitly
create a thread to handle that event. 􀀀One answer is almost, sort of, correct. Wow.
I can understand why you're having problems answering these questiosn. Well, there's no excuse for the questions that come out fo the Javadocs, but for the others ... it explains a lot about the quality of recent graduates.