Add support for Java records (JEP 395, Java 16+)

.gitignore

@@ -11,4 +11,5 @@ target
 **/.settings/ 
 **/.project 
 **/.classpath 
+**/.idea
 pom.xml.versionsBackup

jcodemodel/src/main/java/com/helger/jcodemodel/EClassType.java

@@ -53,7 +53,8 @@ public enum EClassType
   CLASS ("class"),
   INTERFACE ("interface"),
   ANNOTATION_TYPE_DECL ("@interface"),
-  ENUM ("enum");
+  ENUM ("enum"),
+  RECORD ("record");
 
   /**
    * The keyword used to declare this type.

jcodemodel/src/main/java/com/helger/jcodemodel/IJClassContainer.java

@@ -225,6 +225,40 @@ default CLASSTYPE _enum (final int nMods, @NonNull final String sName) throws JC
     return _class (nMods, sName, EClassType.ENUM);
   }
 
+  /**
+   * Add a public record to this package/class.
+   *
+   * @param sName
+   *        Name of the record to be added
+   * @return newly created record
+   * @throws JCodeModelException
+   *         If another class/interface/... with the same name already exists
+   * @since 4.2.0
+   */
+  @NonNull
+  default CLASSTYPE _record (@NonNull final String sName) throws JCodeModelException
+  {
+    return _record (JMod.PUBLIC, sName);
+  }
+
+  /**
+   * Add a record to this package/class.
+   *
+   * @param nMods
+   *        Modifiers for this record declaration
+   * @param sName
+   *        Name of the record to be added
+   * @return newly created record
+   * @throws JCodeModelException
+   *         If another class/interface/... with the same name already exists
+   * @since 4.2.0
+   */
+  @NonNull
+  default CLASSTYPE _record (final int nMods, @NonNull final String sName) throws JCodeModelException
+  {
+    return _class (nMods, sName, EClassType.RECORD);
+  }
+
   /**
    * @return A collection with all nested classes defined in this class. Never <code>null</code>.
    */

jcodemodel/src/main/java/com/helger/jcodemodel/JDefinedClass.java

@@ -142,6 +142,16 @@ public class JDefinedClass extends AbstractJClassContainer <JDefinedClass> imple
    */
   private final Map <String, JEnumConstant> m_aEnumConstantsByName = new LinkedHashMap <> ();
 
+  /**
+   * Record components for record types. Order is significant.
+   */
+  private final List <JRecordComponent> m_aRecordComponents = new ArrayList <> ();
+
+  /**
+   * Compact constructor for record types, if defined.
+   */
+  private JMethod m_aCompactConstructor;
+
   /**
    * Annotations on this variable. Lazily created.
    */
@@ -342,7 +352,7 @@ public JEnumConstant enumConstant (@NonNull final String sName)
 
   /**
    * Check if a specific enum constant name is already in use
-   * 
+   *
    * @param sName
    *        Enum constant name to check. May not be <code>null</code>.
    * @return <code>true</code> if it is contained, <code>false</code> otherwise
@@ -352,6 +362,136 @@ public boolean containsEnumConstant (@NonNull final String sName)
     return m_aEnumConstantsByName.containsKey (sName);
   }
 
+  /**
+   * Adds a component to this record.
+   *
+   * @param aType
+   *        Type of the component. May not be <code>null</code>.
+   * @param sName
+   *        Name of the component. May not be <code>null</code>.
+   * @return The newly created record component.
+   * @throws IllegalStateException
+   *         If this is not a record type.
+   * @since 4.2.0
+   */
+  @NonNull
+  public JRecordComponent recordComponent (@NonNull final AbstractJType aType, @NonNull final String sName)
+  {
+    if (!isRecord())
+      throw new IllegalStateException("recordComponent() is only valid for record types");
+    ValueEnforcer.notNull (aType, "Type");
+    ValueEnforcer.notNull (sName, "Name");
+
+    final JRecordComponent comp = new JRecordComponent (this, aType, sName, false);
+    m_aRecordComponents.add (comp);
+    return comp;
+  }
+
+  /**
+   * Adds a component to this record using a Class reference.
+   *
+   * @param aType
+   *        Type of the component. May not be <code>null</code>.
+   * @param sName
+   *        Name of the component. May not be <code>null</code>.
+   * @return The newly created record component.
+   * @throws IllegalStateException
+   *         If this is not a record type.
+   * @since 4.2.0
+   */
+  @NonNull
+  public JRecordComponent recordComponent (@NonNull final Class <?> aType, @NonNull final String sName)
+  {
+    return recordComponent (owner ().ref (aType), sName);
+  }
+
+  /**
+   * Adds a varargs component to this record. This must be the last component.
+   *
+   * @param aType
+   *        The component type of the varargs array. May not be <code>null</code>.
+   * @param sName
+   *        Name of the component. May not be <code>null</code>.
+   * @return The newly created record component.
+   * @throws IllegalStateException
+   *         If this is not a record type.
+   * @since 4.2.0
+   */
+  @NonNull
+  public JRecordComponent recordComponentVararg (@NonNull final AbstractJType aType, @NonNull final String sName)
+  {
+    if (!isRecord())
+      throw new IllegalStateException("recordComponentVararg() is only valid for record types");
+    ValueEnforcer.notNull (aType, "Type");
+    ValueEnforcer.notNull (sName, "Name");
+
+    final JRecordComponent comp = new JRecordComponent (this, aType.array (), sName, true);
+    m_aRecordComponents.add (comp);
+    return comp;
+  }
+
+  /**
+   * @return The list of record components. Never <code>null</code>.
+   * @since 4.2.0
+   */
+  @NonNull
+  public List <JRecordComponent> recordComponents ()
+  {
+    return Collections.unmodifiableList (m_aRecordComponents);
+  }
+
+  /**
+   * Creates a compact constructor for this record. A compact constructor has no
+   * parameter list and is used for validation or normalization of record components.
+   * <p>
+   * Example:
+   * <pre>
+   * public record Range(int lo, int hi) {
+   *     public Range {
+   *         if (lo &gt; hi) throw new IllegalArgumentException();
+   *     }
+   * }
+   * </pre>
+   *
+   * @param nMods
+   *        Modifiers for this constructor (typically {@link JMod#PUBLIC}).
+   * @return The newly created compact constructor.
+   * @throws IllegalStateException
+   *         If this is not a record type or a compact constructor already exists.
+   * @since 4.2.0
+   */
+  @NonNull
+  public JMethod compactConstructor (final int nMods)
+  {
+    if (!isRecord())
+      throw new IllegalStateException("compactConstructor() is only valid for record types");
+
+    if (m_aCompactConstructor != null)
+      throw new IllegalStateException("A compact constructor has already been defined");
+
+    m_aCompactConstructor = new JMethod (nMods, this);
+    return m_aCompactConstructor;
+  }
+
+  /**
+   * @return The compact constructor if defined, <code>null</code> otherwise.
+   * @since 4.2.0
+   */
+  @Nullable
+  public JMethod compactConstructor ()
+  {
+    return m_aCompactConstructor;
+  }
+
+  /**
+   * @return <code>true</code> if this is a record type.
+   * @since 4.2.0
+   */
+  public boolean isRecord ()
+  {
+    return getClassType () == EClassType.RECORD;
+  }
+
   @Override
   public String binaryName ()
   {
@@ -665,14 +805,31 @@ public void declare (@NonNull final IJFormatter f)
         f.generable (aAnnotation).newline ();
 
     // Modifiers (private, protected, public)
-    // Type of class (class, interface, enum, @interface)
+    // Type of class (class, interface, enum, @interface, record)
     // Name of the class
     // Class wildcards
     f.generable (m_aMods).print (getClassType ().declarationToken ()).id (name ()).declaration (m_aGenerifiable);
 
+    // For records, output the component list
+    if (isRecord ())
+    {
+      f.print ('(');
+      boolean bFirst = true;
+      for (final JRecordComponent comp : m_aRecordComponents)
+      {
+        if (bFirst)
+          bFirst = false;
+        else
+          f.print (',');
+        f.generable (comp);
+      }
+      f.print (')');
+    }
+
     // If a super class is defined and is not "Object"
+    // Note: Records cannot extend classes (they implicitly extend java.lang.Record)
     boolean bHasSuperClass = false;
-    if (m_aSuperClass != null && m_aSuperClass != owner ().ref (Object.class))
+    if (!isRecord () && m_aSuperClass != null && m_aSuperClass != owner ().ref (Object.class))
     {
       bHasSuperClass = true;
       f.newline ().indent ().print ("extends").generable (m_aSuperClass).newline ().outdent ();
@@ -727,7 +884,23 @@ protected void declareBody (@NonNull final IJFormatter f)
     if (m_aInstanceInit != null)
       f.newline ().statement (m_aInstanceInit);
 
-    // All constructors
+    // Compact constructor for records (special syntax without parameter list)
+    if (m_aCompactConstructor != null)
+    {
+      f.newline ();
+      // Output javadoc if present
+      if (m_aCompactConstructor.hasJavadoc ())
+        f.generable (m_aCompactConstructor.javadoc ());
+      // Output annotations
+      for (final JAnnotationUse annotation : m_aCompactConstructor.annotations ())
+        f.generable (annotation).newline ();
+      // Output modifiers and name only (no parentheses)
+      f.generable (m_aCompactConstructor.mods ()).id (name ());
+      // Output body
+      f.statement (m_aCompactConstructor.body ());
+    }
+
+    // All regular constructors
     for (final JMethod m : m_aConstructors)
       f.newline ().declaration (m);
 

jcodemodel/src/main/java/com/helger/jcodemodel/JDocComment.java

@@ -161,6 +161,19 @@ public JCommentPart addParam (@NonNull final JVar sParam)
     return addParam (sParam.name ());
   }
 
+  /**
+   * Append a text to an @param tag for a record component.
+   *
+   * @param aComponent
+   *        Record component to be added
+   * @return The created {@link JCommentPart}
+   * @since 4.2.0
+   */
+  public JCommentPart addParam (@NonNull final JRecordComponent aComponent)
+  {
+    return addParam (aComponent.name ());
+  }
+
   @Nullable
   public JCommentPart removeParam (@Nullable final String sParam)
   {

jcodemodel/src/main/java/com/helger/jcodemodel/JMethod.java

@@ -530,6 +530,15 @@ public JDocComment javadoc ()
     return m_aJDoc;
   }
 
+  /**
+   * @return <code>true</code> if a javadoc comment has been set on this method.
+   * @since 4.2.0
+   */
+  public boolean hasJavadoc ()
+  {
+    return m_aJDoc != null;
+  }
+
   @Override
   public void declare (@NonNull final IJFormatter f)
   {