CS 321 Exam 1, 2, and Quiz 1

In Java, String objects are mutable. (T/F)

False

Java allows multiple inheritance (T/F)

False

Java achieves platform independency mainly though the use of

JVM

Consider parameter passing in Java, which one of the following is true? Java can pass pointers and references Java uses call by value when passing parameters Java cannot pass a primitive value

Java uses call by value when passing parameters

Which of these are not primitive data types? int String Dog char float boolean

String Dog

In Java, any array has a built in variable which stores the length of the array. (T/F)

True

In java.lang.package, there is a Math class. We know that we can use MATH.PI in our programs. This indicates that PI must be a public static class variable of the Math Class. (T/F)

True

java.lang.Object is the root class for Java class hierarchy (t/f)

True

In Java, for WindowEvent, there is a WindowListener interface which has seven methods. If you only want to use one, what design pattern could you use to accomplish this?

adapter

Consider the HotTemperatureException class discussed in class for modeling cars, this exception should be what kind?

checked exception

What are the five C's used to evaluate the implementation of a class?

convenience cohesion completeness clarity consistency

What are the 8 types of primitive data types?

double int float char bool byte long short

java.lang and java.lang.reflect refer to the same package (T/F)

false

The keyword allowing a Java class file to use a premade java package is

import

You want to use another Java package, the keyword to use is:

import

For Java's GUI and event-driven programming, there are three packages which we often need to use/import. What are they?

java.awt* java.Swing* java.awt.event*

Which class in java.io package adapts an InputStream object into a Reader object?

java.io.inputStreamReader

When implementing a JComponent class, there is a method which one needs to pay special attention, for if the method is not overridden, then when the component is resized, the drawing in the component would not be repainted. What is it?

paintComponent()

You want subclasses in any package to have access to members of a superclass. Which is the most restrictive access that accomplishes this objective? public private protected transient

protected

Consider the class, public class Test{} Which constructor is usable by other groups? private Test() Test(void) public Test() public TestConstructor()

public Test()

Which of the following is a valid declaration within an interface definition? public double methoda() public final double methoda() static void methoda(double d1)

public double methoda()

The entry point of a Java program is what function?

public static void main(String args[])

Which is a valid keyword in Java? throw virtual generics unsigned

throw

A final method cannot be overridden by methods in the subclass. (T/F)

true

All the java source files in one particular package have to be placed in the same directory. (T/F)

true

An exception in Java is treated as an object as well. (T/F)

true

Every Java class file is included in a package. (T/F)

true

Every java class/interface is included in a java package. (T/F)

true

The command line arguments in Java are treated as a string array. (T/F)

true

When implementing a class, it is possible for one to use different representations (using different raw materials to build this new kind of objects). (T/F)

true

When writing a java class, what should you do if you want the objects instantiated from the class can be saved directly into files?

use serialization