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<a href="http://www.bruceeckel.com/javabook.html">Bruce Eckel's Thinking in Java</a>
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<H2 ALIGN=LEFT>
Exercises</H2>
<OL>
<LI><FONT FACE="Carmina Md BT" SIZE=5 COLOR="Black">	</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">Create
a class with 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>public</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">,
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>private</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">,
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>protected,</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
and &#8220;friendly&#8221; data members and method members. Create an object of
this class and see what kind of compiler messages you get when you try to
access all the class members. Be aware that classes in the same directory are
part of the &#8220;default&#8221; package.
</FONT><LI><FONT FACE="Carmina Md BT" SIZE=5 COLOR="Black">	</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">Create
a class with 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>protected</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
data. Create a second class in the same file with a method that manipulates the 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>protected</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
data in the first class.
</FONT><LI><FONT FACE="Carmina Md BT" SIZE=5 COLOR="Black">	</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">Create
a new directory and edit your CLASSPATH to include that new directory. Copy the 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>P.class</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
file to your new directory and then change the names of the file, the 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>P</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
class inside and the method names. (You might also want to add additional
output to watch how it works.) Create another program in a different directory
that uses your new class.
</FONT><LI><FONT FACE="Carmina Md BT" SIZE=5 COLOR="Black">	</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">Create
the following file in the c05 directory (presumably in your CLASSPATH):
</FONT></OL>
<font color="#990000"><PRE><font color="#009900">//: PackagedClass.java</font>
<font color="#0000ff">package</font> c05;
<font color="#0000ff">class</font> PackagedClass {
  <font color="#0000ff">public</font> PackagedClass() {
    System.out.println(
      "Creating a packaged <font color="#0000ff">class</font>");
  }
} <font color="#009900">///:~ </PRE></font></font><DIV ALIGN=LEFT><P></DIV><DIV ALIGN=LEFT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">Then
create the following file in a directory other than c05:
</FONT><P></DIV>

<font color="#990000"><PRE><font color="#009900">//: Foreign.java</font>
<font color="#0000ff">package</font> c05.foreign;
<font color="#0000ff">import</font> c05.*;
<font color="#0000ff">public</font> <font color="#0000ff">class</font> Foreign {
   <font color="#0000ff">public</font> <font color="#0000ff">static</font> <font color="#0000ff">void</font> main (String[] args) {
      PackagedClass pc = <font color="#0000ff">new</font> PackagedClass();
   }
} <font color="#009900">///:~ </PRE></font></font><DIV ALIGN=LEFT><P></DIV><DIV ALIGN=LEFT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">Explain
why the compiler generates an error. Would making the 
</FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black"><B>Foreign</B></FONT><FONT FACE="Carmina Md BT" SIZE=3 COLOR="Black">
class part of the c05 package change anything?
</FONT><P></DIV><DIV ALIGN=LEFT><FONT FACE="Da Vinci Extras" SIZE=39 COLOR="Black">k</FONT><a name="Chapter_6"></a><a name="_Toc375545305"></a><a name="_Toc407441450"></a><a name="_Toc408018508"></a><P></DIV>

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