feat(objectionary#636): hide fields of XmlClassProperties

src/main/java/org/eolang/jeo/representation/bytecode/BytecodeClass.java

@@ -185,7 +185,15 @@ public XML xml() {
      */
     public Bytecode bytecode() {
         try {
-            this.props.write(this.visitor, this.name);
+            this.visitor.visit(
+                this.props.version(),
+                this.props.access(),
+                this.name,
+                this.props.signature(),
+                this.props.supername(),
+                this.props.interfaces()
+            );
+
             this.annotations.forEach(annotation -> annotation.write(this.visitor));
             this.fields.forEach(field -> field.write(this.visitor));
             this.methods.forEach(BytecodeMethod::write);

src/main/java/org/eolang/jeo/representation/bytecode/BytecodeClassProperties.java

@@ -23,6 +23,7 @@
  */
 package org.eolang.jeo.representation.bytecode;
 
+import lombok.EqualsAndHashCode;
 import lombok.ToString;
 import org.eolang.jeo.representation.DefaultVersion;
 import org.objectweb.asm.ClassVisitor;
@@ -33,6 +34,7 @@
  * @since 0.1.0
  */
 @ToString
+@EqualsAndHashCode
 public final class BytecodeClassProperties {
 
     /**
@@ -68,6 +70,22 @@ public BytecodeClassProperties(final int access) {
         this(new DefaultVersion().bytecode(), access, null, "java/lang/Object", new String[0]);
     }
 
+    /**
+     * Constructor.
+     * @param access Access modifiers.
+     * @param signature Signature.
+     * @param supername Supername.
+     * @param interfaces Interfaces.
+     */
+    public BytecodeClassProperties(
+        final int access,
+        final String signature,
+        final String supername,
+        final String... interfaces
+    ) {
+        this(new DefaultVersion().bytecode(), access, signature, supername, interfaces);
+    }
+
     /**
      * Constructor.
      * @param version Bytecode version.
@@ -91,6 +109,27 @@ public BytecodeClassProperties(
         this.interfaces = interfaces.clone();
     }
 
+
+    public int version() {
+        return this.version;
+    }
+
+    public int access() {
+        return this.access;
+    }
+
+    public String signature() {
+        return this.signature;
+    }
+
+    public String supername() {
+        return this.supername;
+    }
+
+    public String[] interfaces() {
+        return this.interfaces;
+    }
+
     /**
      * Start writing a class by using a class writer.
      * @param visitor Class visitor.

src/main/java/org/eolang/jeo/representation/xmir/XmlBytecode.java

@@ -84,7 +84,7 @@ public Bytecode bytecode() {
         final XmlClass clazz = program.top();
         final BytecodeClass bytecode = new BytecodeClass(
             new ClassName(program.pckg(), new PrefixedName(clazz.name()).decode()).full(),
-            clazz.properties().toBytecodeProperties(),
+            clazz.properties().bytecode(),
             this.verify
         );
         clazz.annotations().ifPresent(bytecode::withAnnotations);

src/main/java/org/eolang/jeo/representation/xmir/XmlClassProperties.java

@@ -32,15 +32,6 @@
  * XML representation of a class.
  *
  * @since 0.1.0
- * @todo #627:30min Improve Encapsulation of XmlClassProperties.
- *  Currently we are exposing many methods like:
- *  - {@link XmlClassProperties#access()}
- *  - {@link XmlClassProperties#signature()}
- *  - {@link XmlClassProperties#supername()}
- *  - {@link XmlClassProperties#interfaces()}
- *  They are some sort of getters. This encapsulation violation tells us about poor design.
- *  We need to hide this methods and provide a better way to access this properties.
- *  Most probably the problem is deeper than just hiding the methods. We need to rethink the design.
  */
 public final class XmlClassProperties {
 
@@ -53,31 +44,52 @@ public final class XmlClassProperties {
      * Constructor.
      * @param clazz XMl representation of a class.
      */
-    public XmlClassProperties(final XmlNode clazz) {
+    XmlClassProperties(final XmlNode clazz) {
         this(clazz.asDocument());
     }
 
     /**
      * Constructor.
      * @param clazz XML representation of a class.
      */
-    public XmlClassProperties(final XMLDocument clazz) {
+    private XmlClassProperties(final XMLDocument clazz) {
         this.clazz = clazz;
     }
 
+    /**
+     * Convert to bytecode properties.
+     * @return Bytecode properties.
+     */
+    public BytecodeClassProperties bytecode() {
+        try {
+            return new BytecodeClassProperties(
+                this.version(),
+                this.access(),
+                this.signature(),
+                this.supername(),
+                this.interfaces()
+            );
+        } catch (final IllegalArgumentException exception) {
+            throw new IllegalArgumentException(
+                String.format("Invalid class properties: %s", this.clazz),
+                exception
+            );
+        }
+    }
+
     /**
      * Retrieve 'access' modifiers of a class.
      * @return Access modifiers.
      */
-    public int access() {
+    private int access() {
         return new HexString(this.clazz.xpath("./o[@name='access']/text()").get(0)).decodeAsInt();
     }
 
     /**
      * Retrieve 'signature' of a class.
      * @return Signature.
      */
-    public String signature() {
+    private String signature() {
         return this.clazz.xpath("./o[@name='signature']/text()")
             .stream()
             .map(HexString::new)
@@ -90,7 +102,7 @@ public String signature() {
      * Retrieve 'supername' of a class.
      * @return Supername.
      */
-    public String supername() {
+    private String supername() {
         return this.clazz.xpath("./o[@name='supername']/text()")
             .stream()
             .map(HexString::new)
@@ -102,7 +114,7 @@ public String supername() {
      * Retrieve 'interfaces' of a class.
      * @return Interfaces.
      */
-    public String[] interfaces() {
+    private String[] interfaces() {
         return this.clazz.xpath("./o[@name='interfaces']/o/text()")
             .stream()
             .map(HexString::new)
@@ -113,7 +125,7 @@ public String[] interfaces() {
      * Retrieve bytecode 'version'.
      * @return Bytecode version.
      */
-    int version() {
+    private int version() {
         final List<String> version = this.clazz.xpath("./o[@name='version']/text()");
         final int result;
         if (version.isEmpty()) {
@@ -123,26 +135,5 @@ int version() {
         }
         return result;
     }
-
-    /**
-     * Convert to bytecode properties.
-     * @return Bytecode properties.
-     */
-    BytecodeClassProperties toBytecodeProperties() {
-        try {
-            return new BytecodeClassProperties(
-                this.version(),
-                this.access(),
-                this.signature(),
-                this.supername(),
-                this.interfaces()
-            );
-        } catch (final IllegalArgumentException exception) {
-            throw new IllegalArgumentException(
-                String.format("Invalid class properties: %s", this.clazz),
-                exception
-            );
-        }
-    }
 }
 

src/test/java/org/eolang/jeo/representation/directives/DirectivesClassTest.java

@@ -27,6 +27,7 @@
 import com.jcabi.xml.XMLDocument;
 import org.eolang.jeo.matchers.SameXml;
 import org.eolang.jeo.representation.ClassName;
+import org.eolang.jeo.representation.bytecode.BytecodeClassProperties;
 import org.eolang.jeo.representation.xmir.XmlClass;
 import org.eolang.jeo.representation.xmir.XmlNode;
 import org.hamcrest.MatcherAssert;
@@ -125,24 +126,16 @@ void convertsToDirectives() throws ImpossibleModificationException {
             Matchers.equalTo(name)
         );
         MatcherAssert.assertThat(
-            "Class access is not equal to expected",
-            clazz.properties().access(),
-            Matchers.equalTo(access)
-        );
-        MatcherAssert.assertThat(
-            "Class signature is not equal to expected",
-            clazz.properties().signature(),
-            Matchers.equalTo(signature)
-        );
-        MatcherAssert.assertThat(
-            "Class supername is not equal to expected",
-            clazz.properties().supername(),
-            Matchers.equalTo(supername)
-        );
-        MatcherAssert.assertThat(
-            "Class interface is not equal to expected",
-            clazz.properties().interfaces()[0],
-            Matchers.equalTo(interfce)
+            "Class properties are not equal to expected",
+            clazz.properties().bytecode(),
+            Matchers.equalTo(
+                new BytecodeClassProperties(
+                    access,
+                    signature,
+                    supername,
+                    interfce
+                )
+            )
         );
     }
 

src/test/java/org/eolang/jeo/representation/xmir/XmlClassPropertiesTest.java

@@ -42,7 +42,7 @@ void retrievesAccessModifier() {
         final int actual = new XmlClass(
             "Language",
             new DirectivesClassProperties(expected)
-        ).properties().access();
+        ).properties().bytecode().access();
         MatcherAssert.assertThat(
             String.format(
                 "Can't retrieve access modifier correctly, expected %d (public abstract class), got %d",
@@ -59,7 +59,7 @@ void retrievesSignature() {
         final String expected = "Ljava/util/List<Ljava/lang/String;>;";
         final String actual = new XmlClass(
             new DirectivesClassProperties(0, expected)
-        ).properties().signature();
+        ).properties().bytecode().signature();
         MatcherAssert.assertThat(
             String.format(
                 "Can't retrieve signature correctly, expected %s, got %s",
@@ -76,6 +76,7 @@ void retrievesSupernameIfDefined() {
         final String expected = "some/custom/Supername";
         final String supername = new XmlClass(new DirectivesClassProperties(0, "", expected))
             .properties()
+            .bytecode()
             .supername();
         MatcherAssert.assertThat(
             String.format(
@@ -93,6 +94,7 @@ void retrievesSupernameIfItIsNotDefinedExplicitly() {
         final String expected = "java/lang/Object";
         final String supername = new XmlClass("DefaultClass")
             .properties()
+            .bytecode()
             .supername();
         MatcherAssert.assertThat(
             String.format(
@@ -110,6 +112,7 @@ void retrievesInterfacesIfTheyAreDefined() {
         final String[] expected = {"java/util/List", "java/util/Collection"};
         final String[] interfaces = new XmlClass(new DirectivesClassProperties(0, "", "", expected))
             .properties()
+            .bytecode()
             .interfaces();
         MatcherAssert.assertThat(
             String.format(
@@ -126,6 +129,7 @@ void retrievesInterfacesIfTheyAreDefined() {
     void retrievesInterfacesIfTheyAreNotDefinedExplicitly() {
         final String[] interfaces = new XmlClass("WithoutIntefaces")
             .properties()
+            .bytecode()
             .interfaces();
         MatcherAssert.assertThat(
             String.format(