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<TD vAlign=center><FONT face=Courier>Thread t = new
Thread(targetObject);</FONT></TD></TR></TBODY></TABLE>What test of <FONT
face=Courier>instanceof</FONT> does <FONT face=Courier>targetObject</FONT>
have to pass for this to be legal?
<P>Select the one right answer.
<P>
<OL type=a>
<LI><FONT face=Courier>targetObject instanceof Thread</FONT>
<LI><FONT face=Courier>targetObject instanceof Object</FONT>
<LI><FONT face=Courier>targetObject instanceof Applet</FONT>
<LI><FONT face=Courier>targetObject instanceof Runnable</FONT>
<LI><FONT face=Courier>targetObject instanceof String</FONT> </LI></OL>
<P>
<P><B>Question 47</B>: What appears in the standard output when you run
the Dots class?
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier>class Dots implements Runnable
{</FONT>
<DIR><FONT face=Courier>DotThread t;</FONT>
<P><FONT face=Courier>public static void main(String[] args)
{</FONT>
<DIR><FONT face=Courier>Dots d = new Dots();</FONT>
<P><FONT face=Courier>d.t = new DotThread();</FONT></P></DIR><FONT
face=Courier>}</FONT>
<P><FONT face=Courier>public void init() {</FONT>
<DIR><FONT face=Courier>t.start();</FONT>
<P><FONT face=Courier>t = new
DashThread().start();</FONT></P></DIR><FONT
face=Courier>}</FONT></DIR><FONT face=Courier>}</FONT>
<P><FONT face=Courier></FONT>
<P><FONT face=Courier>class DotThread extends Thread {</FONT>
<DIR><FONT face=Courier>public void run() {</FONT>
<DIR><FONT face=Courier>for (int index = 0; index < 100;
index++) </FONT>
<DIR><FONT
face=Courier>System.out.print(".");</FONT></DIR></DIR><FONT
face=Courier>}</FONT></DIR><FONT face=Courier>}</FONT>
<P><FONT face=Courier>class DashThread extends Thread {</FONT>
<DIR><FONT face=Courier>public void run() {</FONT>
<DIR><FONT face=Courier>for (int index = 0; index < 100;
index++) </FONT>
<DIR><FONT
face=Courier>System.out.print("-");</FONT></DIR></DIR><FONT
face=Courier>}</FONT></DIR><FONT
face=Courier>}</FONT></TD></TR></TBODY></TABLE>
<OL type=a>
<LI>nothing
<LI>100 dots (.)
<LI>200 dots (.)
<LI>100 dashes (-)
<LI>100 dots (.) and 100 dashes(-) </LI></OL>
<P><B>Question 48</B>: When you invoke <FONT face=Courier>repaint()</FONT>
for a Component, the AWT package calls which Component method?
<P>
<OL type=a>
<LI><FONT face=Courier>repaint()</FONT>
<LI><FONT face=Courier>update()</FONT>
<LI><FONT face=Courier>paint()</FONT>
<LI><FONT face=Courier>draw()</FONT>
<LI><FONT face=Courier>show()</FONT> </LI></OL>
<P><B>Question 49</B>: How you can you test whether an object referenced
by <FONT face=Courier>ref</FONT> implements an interface named
MyInterface? Replace <FONT face=Courier>your test here</FONT> with this
test:
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier>if (your test here) {</FONT>
<DIR><FONT face=Courier>System.out.println("ref implements
MyInterface");</FONT></DIR></TD></TR></TBODY></TABLE>Fill in the blank.
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT
face=Courier> </FONT></TD></TR></TBODY></TABLE><B>Question 50</B>:
What does the following line of code do?
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier>TextField tf = new
TextField(30);</FONT></TD></TR></TBODY></TABLE>Select the one right
answer.
<P>
<OL type=a>
<LI>This code is illegal; there is no such constructor for TextField.
<LI>Creates a TextField object that can hold 30 rows, but since it is
not initialized to anything, it will always be empty.
<LI>Creates a TextField object that can hold 30 columns, but since it is
not initialized to anything, it will always be empty.
<LI>This code creates a TextField object that can hold 30 rows of text.
<LI>Creates a new TextField object that is 30 columns of text. </LI></OL>
<P><B>Question 51</B>: Given these code snippets:
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier>Boolean b1 = new
Boolean(true);</FONT>
<P><FONT face=Courier>Boolean b2 = new
Boolean(true);</FONT></P></TD></TR></TBODY></TABLE>Which expressions are
legal Java expressions that return <FONT face=Courier>true</FONT>?
<P>Select all valid answers.
<P>
<OL type=a>
<LI><FONT face=Courier>b1 == b2</FONT>
<LI><FONT face=Courier>b1.equals(b2)</FONT>
<LI><FONT face=Courier>b1 & b2</FONT>
<LI><FONT face=Courier>b1 | b2</FONT>
<LI><FONT face=Courier>b1 && b2</FONT>
<LI><FONT face=Courier>b1 || b2</FONT> </LI></OL>
<P><B>Question 52</B>: Which LayoutManager arranges components left to
right, then top to bottom, centering each row as it moves to the next?
<P>Select the one right answer.
<P>
<OL type=a>
<LI>BorderLayout
<LI>FlowLayout
<LI>GridLayout
<LI>CardLayout
<LI>GridBagLayout </LI></OL>
<P>
<P><B>Question 53</B>: A component can be resized horizontally, but not
vertically, when it is placed in which region of a BorderLayout?
<P>Select the one right answer.
<P>
<OL type=a>
<LI>North or South
<LI>East or West
<LI>Center
<LI>North, South, or Center
<LI>any region </LI></OL>
<P>
<P><B>Question 54</B>: How can you place three Components along the bottom
of a Container?
<P>Select the one right answer.
<P>
<OL type=a>
<LI>Set the Container's LayoutManager to be a BorderLayout and add each
Component to the "South" of the Container .
<LI>Set the Container's LayoutManager to be a FlowLayout and add each
Component to the Container.
<LI>Set the Container's LayoutManager to be a BorderLayout; add each
Component to a different Container that uses a FlowLayout, and then add
that Container to the "South" of the first Container.
<LI>Use a GridLayout for the Container and add each Component to the
Container.
<LI>Do not use a LayoutManager at all and add each Component to the
Container. </LI></OL>
<P>
<P><B>Question 55</B>: What will happen when you attempt to compile and
run the following program by passing the Test class to the Java
interpreter?
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier>class Test {</FONT>
<DIR><FONT face=Courier>public static void main() {</FONT>
<DIR><FONT
face=Courier>System.out.println("hello");</FONT></DIR><FONT
face=Courier>}</FONT></DIR><FONT
face=Courier>}</FONT></TD></TR></TBODY></TABLE>Select the one right
answer.
<P>
<P>
<OL type=a>
<LI>The program does not compile because <FONT
face=Courier>main()</FONT> is not defined correctly.
<LI>The program compiles but when you try to run the interpreter
complains that it cannot find the <FONT face=Courier>main()</FONT>
method it needs to run.
<LI>The program compiles but you cannot run it because the class is not
declared as <FONT face=Courier>public</FONT>.
<LI>The program compiles and runs without an error but does not display
anything in the standard output.
<LI>The program compiles and displays "hello" in the standard output
when you run it. </LI></OL>
<P>
<P><B>Question 56</B>: Which of the following is a valid way to embed an
applet class named Q56 into a Web page?
<P>Select all right answers.
<P>a)
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier><applet class=Q56.class
width=100 height=100> </FONT>
<P><FONT
face=Courier></applet></FONT></P></TD></TR></TBODY></TABLE>b)
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier><applet code=Q56 width=100
height=100> </FONT>
<P><FONT
face=Courier></applet></FONT></P></TD></TR></TBODY></TABLE>c)
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier><applet code=Q56.class
width=100 height=100> </FONT>
<P><FONT
face=Courier></applet></FONT></P></TD></TR></TBODY></TABLE>d)
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier><applet param=Q56.class
width=100 height=100> </FONT>
<P><FONT
face=Courier></applet></FONT></P></TD></TR></TBODY></TABLE>e)
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier><applet param=Q56 width=100
height=100> </FONT>
<P><FONT
face=Courier></applet></FONT></P></TD></TR></TBODY></TABLE><B>Question
57</B>: How would you make the background color red for a Panel referenced
by the variable <FONT face=Courier>p</FONT>?
<P>Fill in the blank.
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT
face=Courier> </FONT></TD></TR></TBODY></TABLE><B>Question 58</B>:
How can you retrieve a circle抯 radius value that抯 passed to an applet?
<P>a)
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier>public void init() {</FONT>
<DIR><FONT face=Courier>String s = getParameter("radius");</FONT>
<P><FONT
face=Courier>doSomethingWithRadius(s);</FONT></P></DIR><FONT
face=Courier>}</FONT></TD></TR></TBODY></TABLE>b)
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier>public static void
main(String[] args) {</FONT>
<DIR><FONT face=Courier>String s = args[0];</FONT>
<P><FONT
face=Courier>DoSomethingWithRadius(s);</FONT></P></DIR><FONT
face=Courier>}</FONT></TD></TR></TBODY></TABLE>c)
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier>public static void
main(String[] args) {</FONT>
<DIR><FONT face=Courier>String s = getParameter("radius");</FONT>
<P><FONT
face=Courier>DoSomethingWithRadius(s);</FONT></P></DIR><FONT
face=Courier>}</FONT></TD></TR></TBODY></TABLE>d)
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier>public void init() {</FONT>
<DIR><FONT face=Courier>int radius = getParameter("radius");</FONT>
<P><FONT
face=Courier>doSomethingWithRadius(radius);</FONT></P></DIR><FONT
face=Courier>}</FONT></TD></TR></TBODY></TABLE>e)
<TABLE width="100%" border=1>
<TBODY>
<TR>
<TD vAlign=center><FONT face=Courier>public void init() {</FONT>
<DIR><FONT face=Courier>int radius = getParameter();</FONT>
<P><FONT
face=Courier>doSomethingWithRadius(radius);</FONT></P></DIR><FONT
face=Courier>}</FONT></TD></TR></TBODY></TABLE>
<P><B>Question 59</B>: What is the result of invoking <FONT
face=Courier>main()</FONT> for the classes D and E?
<TABLE width="100%" border=1>
<TBODY>
<TR>
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