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+<?xml version="1.0" standalone="no"?>
+<!DOCTYPE document PUBLIC "-//APACHE//DTD Documentation V1.1//EN"
+    "http://cvs.apache.org/viewcvs.cgi/*checkout*/xml-forrest/src/resources/schema/dtd/document-v11.dtd">
+
+<document>
+    <header>
+        <title>Properties$classes</title>
+    <authors>
+      <person name="Peter B. West" email="pbwest@powerup.com.au"/>
+    </authors>
+    </header>
+    <body>
+    <section>
+      <title>fo.Properties and the nested properties classes</title>
+      <figure src="PropertyClasses.png" alt="Nested property and
+        top-level classes"/> 
+      <section>
+        <title>Nested property classes</title>
+  <p>
+    Given the intention that individual properties have only a
+    <em>virtual</em> instantiation in the arrays of
+    <code>PropertyConsts</code>, these classes are intended to
+    remain as repositories of static data and methods.  The name
+    of each property is entered in the
+    <code>PropNames.propertyNames</code> array of
+    <code>String</code>s, and each has a unique integer constant
+    defined, corresponding to the offset of the property name in
+    that array.
+  </p>
+  <section>
+    <title>Fields common to all classes</title>
+    <dl> 
+      <dt><code>final int dataTypes</code></dt>
+      <dd>
+        This field defines the allowable data types which may be
+        assigned to the property.  The value is chosen from the
+        data type constants defined in <code>Properties</code>, and
+        may consist of more than one of those constants,
+        bit-ORed together.
+      </dd>
+      <dt><code>final int traitMapping</code></dt>
+      <dd>
+        This field defines the mapping of properties to traits
+        in the <code>Area tree</code>. The value is chosen from the
+        trait mapping constants defined in <code>Properties</code>,
+        and may consist of more than one of those constants,
+        bit-ORed together.
+      </dd>
+      <dt><code>final int initialValueType</code></dt>
+      <dd>
+        This field defines the data type of the initial value
+        assigned to the property.  The value is chosen from the
+        initial value type constants defined in
+        <code>Properties</code>.
+      </dd>
+      <dt><code>final int inherited</code></dt>
+      <dd>
+        This field defines the kind of inheritance applicable to
+        the property.  The value is chosen from the inheritance
+        constants defined in <code>Properties</code>. 
+      </dd>
+    </dl>
+  </section>
+  <section>
+    <title>Datatype dependent fields</title>
+    <dl>
+      <dt>Enumeration types</dt>
+      <dd>
+        <strong><code>final String[] enums</code></strong><br/>
+        This array contains the <code>NCName</code>  text
+        values of the enumeration.  In the current
+        implementation, it always contains a null value at
+        <code>enum[0]</code>.<br/> <br/>
+
+        <strong><code>final String[]
+        enumValues</code></strong><br/> When the number of
+        enumeration values is small,
+        <code>enumValues</code>  is a reference to the
+        <code>enums</code>  array.<br/> <br/>
+
+        <strong><code>final HashMap
+        enumValues</code></strong><br/> When the number of
+        enumeration values is larger,
+        <code>enumValues</code>  is a
+        <code>HashMap</code>  statically initialized to
+        contain the integer constant values corresponding to
+        each text value, indexed by the text
+        value.<br/> <br/>
+
+        <strong><code>final int</code></strong>
+        <em><code>enumeration-constants</code></em><br/> A
+        unique integer constant is defined for each of the
+        possible enumeration values.<br/> <br/>
+      </dd>
+      <dt>Many types:
+        <code>final</code>  <em>datatype</em>
+        <code>initialValue</code></dt>
+      <dd>
+        When the initial datatype does not have an implicit
+        initial value (as, for example, does type
+        <code>AUTO</code>) the initial value for the property is
+        assigned to this field.  The type of this field will
+        vary according to the <code>initialValueType</code>
+        field.
+      </dd>
+      <dt>AUTO: <code>PropertyValueList auto(property,
+        list)></code></dt>
+      <dd>
+        When <em>AUTO</em>  is a legal value type, the
+        <code>auto()</code>  method must be defined in the property
+        class.<br/>
+        <em>NOT YET IMPLEMENTED.</em>
+      </dd>
+      <dt>COMPLEX: <code>PropertyValueList complex(property,
+        list)></code></dt>
+      <dd>
+        <em>COMPLEX</em>  is specified as a value type when complex
+        conditions apply to the selection of a value type, or
+        when lists of values are acceptable.  To process and
+        validate such a property value assignment, the
+        <code>complex()</code>  method must be defined in the
+        property class.
+      </dd>
+    </dl>
+  </section>
+      </section>
+      <section>
+        <title>Nested property pseudo-classes</title>
+  <p>
+    The property pseudo-classes are classes, like
+    <code>ColorCommon</code>  which contain values, particularly
+    <em>enums</em>, which are common to a number of actual
+    properties.
+  </p>
+      </section>
+      <p>
+  <strong>Previous:</strong> <link href= "classes-overview.html"
+  >property classes overview.</link>
+      </p>
+    </section>
+    </body>
+</document>
+