From 18a15aa838c1d72f6f11e085e362c53c0955908e Mon Sep 17 00:00:00 2001
From: "Dr. Martin Goik" <goik@hdm-stuttgart.de>
Date: Thu, 9 May 2019 13:50:28 +0200
Subject: [PATCH] Cosmetics
---
Doc/Sd1/objectsClasses.xml | 118 ++++++++++++++++++++++++++-----------
1 file changed, 82 insertions(+), 36 deletions(-)
diff --git a/Doc/Sd1/objectsClasses.xml b/Doc/Sd1/objectsClasses.xml
index dcda5041e..3d64a2620 100644
--- a/Doc/Sd1/objectsClasses.xml
+++ b/Doc/Sd1/objectsClasses.xml
@@ -3902,27 +3902,64 @@ seconds = 23</screen></td>
</itemizedlist>
</figure>
+ <figure xml:id="sd1_fig_MemberConstructorImplement">
+ <title>Implementing club members.</title>
+
+ <programlisting language="java">public class ClubMember {
+
+ final private String name;
+
+ public ClubMember(final String name) {
+ this.name = name;
+ }
+ public String getDetails() {
+ return "Member " + name;
+ }
+}</programlisting>
+ </figure>
+
+ <figure xml:id="sd1_fig_MembershipInfo">
+ <title>Showing membership info.</title>
+
+ <informaltable border="0">
+ <tr>
+ <td valign="top"><programlisting language="java">final ClubMember
+ john = new ClubMember("John"),
+ karen = new ClubMember("Karen");
+
+System.out.println(john.getDetails());
+System.out.println(karen.getDetails());
+</programlisting></td>
+
+ <td valign="top"><screen>Member John
+Member Karen</screen></td>
+ </tr>
+ </informaltable>
+ </figure>
+
<figure xml:id="sd1_fig_staticMemberConstructorImplement">
<title>Implementing membership numbers.</title>
- <programlisting language="java">public class ClubMember {
+ <programlisting language="java">emphapublic class ClubMember {
- static <co linkends="sd1_callout_clubStaticMembercount-1"
- xml:id="sd1_callout_clubStaticMembercount-1-co"/> private int memberCount = 0;
+ <emphasis role="red">static</emphasis> <co
+ linkends="sd1_callout_clubStaticMembercount-1"
+ xml:id="sd1_callout_clubStaticMembercount-1-co"/> <emphasis
+ role="red">private int memberCount = 0;</emphasis>
- final private int memberNumber; <co
+ <emphasis role="red">final private int memberNumber;</emphasis> <co
linkends="sd1_callout_clubStaticMembercount-2"
xml:id="sd1_callout_clubStaticMembercount-2-co"/>
final private String name;
public ClubMember(final String name) {
this.name = name;
- memberNumber = ++memberCount; <co
+ <emphasis role="red">memberNumber = ++memberCount;</emphasis> <co
linkends="sd1_callout_clubStaticMembercount-3"
xml:id="sd1_callout_clubStaticMembercount-3-co"/>
}
public String getDetails() {
- return "Member " + name + ", member number " + memberNumber <co
+ return "Member " + name <emphasis role="red">+ ", member number " + memberNumber</emphasis> <co
linkends="sd1_callout_clubStaticMembercount-4"
xml:id="sd1_callout_clubStaticMembercount-4-co"/>;
}
@@ -3947,25 +3984,25 @@ seconds = 23</screen></td>
<callout arearefs="sd1_callout_clubStaticMembercount-3-co"
xml:id="sd1_callout_clubStaticMembercount-3">
- <para>Whenever a new instance of <classname>ClubMember</classname>
- is being created two things happen:</para>
+ <para>On creating a new instance of
+ <classname>ClubMember</classname> two actions happen:</para>
<orderedlist>
<listitem>
<para>The overall <varname>memberCount</varname> variable is
- being incremented.</para>
+ being incremented by one.</para>
</listitem>
<listitem>
- <para>The new club's member count is being assigned to the
- current instance.</para>
+ <para>The new club's overall member count is being assigned to
+ the current instance.</para>
</listitem>
</orderedlist>
</callout>
<callout arearefs="sd1_callout_clubStaticMembercount-4-co"
xml:id="sd1_callout_clubStaticMembercount-4">
- <para>Accessing an instance's membership number.</para>
+ <para>Accessing an individual member's membership number.</para>
</callout>
</calloutlist>
</figure>
@@ -3973,19 +4010,23 @@ seconds = 23</screen></td>
<figure xml:id="sd1_fig_staticMembershipNumberInfo">
<title>Showing membership numbers.</title>
- <programlisting language="java">public static void main(String[] args) {
-
- final ClubMember john = new ClubMember("John"),
- karen = new ClubMember("Karen");
+ <informaltable border="0">
+ <tr>
+ <td valign="top"><programlisting language="java">final ClubMember
+ john = new ClubMember("John"),
+ karen = new ClubMember("Karen");
- System.out.println(karen.getDetails());
-}</programlisting>
+System.out.println(john.getDetails());
+System.out.println(karen.getDetails());</programlisting></td>
- <screen>Member Karen, member number 2</screen>
+ <td valign="top"><screen>Member John, member number 1
+Member Karen, member number 2</screen></td>
+ </tr>
+ </informaltable>
</figure>
<figure xml:id="sd1_fig_staticAccessorMemberCount">
- <title>Access to the club's overall member count?</title>
+ <title>Accessing the club's overall member count?</title>
<programlisting language="java">public class ClubMember {
@@ -4024,19 +4065,23 @@ seconds = 23</screen></td>
<figure xml:id="sd1_fig_staticAccessMemberCountImplement">
<title>Accessing the club's member count</title>
- <programlisting language="java">final ClubMember
+ <informaltable border="0">
+ <tr>
+ <td valign="top"><programlisting language="java">final ClubMember
john = new ClubMember("John"),
karen = new ClubMember("Karen"),
petra = new ClubMember("Petra");
- System.out.println(karen.getDetails());
+System.out.println(karen.getDetails());
- System.out.println("Club's member count:" +
- ClubMember.getMemberCount()); // Good: Prevent tampering
-} // memberCount variable.</programlisting>
+System.out.println("Club's member count:" +
+ ClubMember.getMemberCount());// Good: Prevent tampering
+ // memberCount variable.</programlisting></td>
- <screen>Member Karen, member number 2
-Club's member count:3</screen>
+ <td valign="top"><screen>Member Karen, member number 2
+Club's member count:3</screen></td>
+ </tr>
+ </informaltable>
</figure>
<figure xml:id="sd1_fig_staticNoInstanceNeeded">
@@ -4062,7 +4107,7 @@ System.out.println("Maximum: " +
</tr>
</informaltable>
- <para>Observation: Object state irrelevant.</para>
+ <para>Observation: Instance state irrelevant.</para>
</figure>
<figure xml:id="sd1_fig_staticStateIndependentMethods">
@@ -4196,10 +4241,11 @@ model/ClubMember.java:20: error: non-static variable memberNumber
number. <code language="java">static</code> methods are being
defined on class rather than on instance level. According to
<xref linkend="sd1_fig_syntaxAccessClassMembersMethodDef"/>
- execution happens by calling ClubMember.getDetails(). Thus
- there is no instance involved and thus both instance variables
- <emphasis role="red">name</emphasis> and <emphasis
- role="red">memberNumber</emphasis> are invisible.</para>
+ execution happens by calling ClubMember.getDetails(). There is
+ thus no instance involved and consequently both instance
+ variables <emphasis role="red">name</emphasis> and <emphasis
+ role="red">memberNumber</emphasis> do not exist in any static
+ context.</para>
</listitem>
<listitem>
@@ -4229,8 +4275,8 @@ System.out.println("Club's headcount:" + <emphasis role="red">john.</emphasis>ge
<para>This is actually a regression with respect to the <code
language="java">static</code> class method variant since the
- number of club members in fact does not depend on individual
- member instances.</para>
+ number of club members in fact does not depend on any
+ individual member instance. </para>
<para>We may reveal this changes futility by:</para>
@@ -4250,8 +4296,8 @@ System.out.println("Club's headcount:" + <emphasis role="red">petra</emphasis>.g
<para>Even worse: Without creating an instance of
<classname>ClubMember</classname> we can no longer access the
- club's overall member count. But even without any member we
- still do have a valid member count of zero.</para>
+ club's overall member count. But even without any member
+ instance we still have a valid member count of zero.</para>
</listitem>
</orderedlist>
</answer>
--
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