Tech Tips Programming Quiz

J2SE Platform: Development Kits & General Programming

Why are Java ARchive (JAR) files important?

Answer (B): They bundle .class files and optimize applet loading.

Which code segment ensures garbage collection happens in a timely manner?

Answer (A): Nullifying an object reference facilitates garbage collection.

          public Object pop()
          {
            Object p = stk[stkp];
            stk[stkp--] = null;>
            return p;
          }

What is the purpose of the toolkit in the Abstract Window Toolkit (AWT)?

Answer (C): An interface between the abstract window layer and windowing implementation.
What is an interface class?

A collection of method declarations and constant values.
Vertical and horizontal scroll bar increments are how many units by default?

Answer (D): 1 unit.
Reflection (introspection) is querying a class about its properties, and operating on methods and fields by the name for a given object instance. Why is reflection possible in the Java language?

Answer (A): Late binding.
The StringBuffer class supports what type of strings?

Answer (A): Mutable (changeable).
Why does an Assert class that checks program assertions need several implementations of its assert method?

Answer (B):The Java language has tight type checking. You need an assert implementation for booleans, byte, char, short, int, long, float, double, and all reference types.
What is serialization?

Answer (D): A way to convert objects into a stream of bytes.
What is javap?

Answer (C): A tool for generating information on .class files

You missed 0
Your score is 100 percent.