feat: extend the existingJavaTypes to support use of existing enumerations.

CHANGELOG.md

@@ -16,6 +16,8 @@
 
 #### New Features
 
+* Fix #7045: (java-generator)  Extend the existingJavaTypes to support use of existing enumerations
+
 #### _**Note**_: Breaking changes
 
 ### 6.14.0 (2025-06-10)

java-generator/core/src/main/java/io/fabric8/java/generator/nodes/AbstractJSONSchema2Pojo.java

@@ -327,6 +327,7 @@ private static AbstractJSONSchema2Pojo fromJsonSchema(
             throw new JavaGeneratorException("Unsupported enumeration type/format: " + prop.getType() + "/" + prop.getFormat());
         }
         return new JEnum(
+            parentPkg,
             key,
             enumType,
             prop.getEnum(),

java-generator/core/src/main/java/io/fabric8/java/generator/nodes/JEnum.java

@@ -47,20 +47,38 @@ public class JEnum extends AbstractJSONSchema2Pojo {
   private final String underlyingType;
   private final Set<String> values; //Let's prevent duplicates
 
-  public JEnum(String type, String underlyingType, List<JsonNode> values, Config config, String description,
-      final boolean isNullable,
-      JsonNode defaultValue) {
+  // Used for matching against existing types.
+  private final String pkgPrefixedType;
+
+  public JEnum(String pkg, String type, String underlyingType, List<JsonNode> values, Config config, String description,
+      final boolean isNullable, JsonNode defaultValue) {
     super(config, description, isNullable, defaultValue, null);
     this.type = AbstractJSONSchema2Pojo.sanitizeString(
         type.substring(0, 1).toUpperCase() + type.substring(1));
     this.underlyingType = underlyingType;
     //Tests assume order so let's use LinkedHashSet instead of just using Collectors.toSet()
     this.values = values.stream().map(JsonNode::asText).collect(Collectors.toCollection(LinkedHashSet::new));
+    this.pkgPrefixedType = createPackagePrefixedType(pkg, this.type);
+  }
+
+  /**
+   * @deprecated use {@link #JEnum(String, String, String, List, Config, String, boolean, JsonNode)}
+   */
+  @Deprecated
+  public JEnum(String type, String underlyingType, List<JsonNode> values, Config config, String description,
+      final boolean isNullable, JsonNode defaultValue) {
+    this(null, type, underlyingType, values, config, description, isNullable, defaultValue);
+  }
+
+  private String createPackagePrefixedType(String pkg, String type) {
+    String p = (pkg == null) ? "" : pkg.trim();
+    String pkgPrefix = (p.isEmpty()) ? p : p + ".";
+    return pkgPrefix + type;
   }
 
   @Override
   public String getType() {
-    return this.type;
+    return config.getExistingJavaTypes().getOrDefault(this.pkgPrefixedType, this.type);
   }
 
   private String sanitizeEnumEntry(final String str) {
@@ -93,6 +111,10 @@ private Statement generateBooleanCreator(boolean hasTrue, boolean hasFalse) {
 
   @Override
   public GeneratorResult generateJava() {
+    if (config.getExistingJavaTypes().containsKey(pkgPrefixedType)) {
+      return new GeneratorResult(Collections.emptyList());
+    }
+
     CompilationUnit cu = new CompilationUnit();
     EnumDeclaration en = cu.addEnum(this.type);
 

java-generator/core/src/test/java/io/fabric8/java/generator/GeneratorTest.java

@@ -448,6 +448,7 @@ void testDefaultEnum() {
     enumValues.add(new TextNode("baz"));
     props.put("e1", newEnum);
     JEnum enu = new JEnum(
+        "pkg",
         "t",
         JAVA_LANG_STRING,
         enumValues,
@@ -484,6 +485,7 @@ void testLongEnum() {
     enumValues.add(new TextNode("3"));
     props.put("e1", newEnum);
     JEnum enu = new JEnum(
+        "pkg",
         "t",
         JAVA_LANG_LONG,
         enumValues,
@@ -524,6 +526,7 @@ void testIntEnum() {
     enumValues.add(new TextNode("3"));
     props.put("e1", newEnum);
     JEnum enu = new JEnum(
+        "pkg",
         "t",
         JAVA_LANG_INTEGER,
         enumValues,
@@ -562,6 +565,7 @@ void testBooleanEnum() {
     enumValues.add(new TextNode("false"));
     props.put("e1", newEnum);
     JEnum enu = new JEnum(
+        "pkg",
         "t",
         JAVA_PRIMITIVE_BOOLEAN,
         enumValues,
@@ -600,6 +604,7 @@ void testNotUppercaseEnum() {
     enumValues.add(new TextNode("baz"));
     props.put("e1", newEnum);
     JEnum enu = new JEnum(
+        "pkg",
         "t",
         JAVA_LANG_STRING,
         enumValues,
@@ -624,6 +629,32 @@ void testNotUppercaseEnum() {
     assertEquals("baz", en.get().getEntries().get(2).getName().asString());
   }
 
+  @Test
+  void testEnumDeprecatedConstructor() {
+    // Arrange
+    JSONSchemaProps newEnum = new JSONSchemaProps();
+    newEnum.setType("string");
+    JEnum enu = new JEnum(
+        "t",
+        JAVA_LANG_STRING,
+        List.of(),
+        defaultConfig,
+        null,
+        Boolean.FALSE,
+        null);
+
+    // Act
+    GeneratorResult res = enu.generateJava();
+
+    // Assert
+    assertEquals("T", enu.getType());
+    assertEquals(1, res.getInnerClasses().size());
+    assertEquals("T", res.getInnerClasses().get(0).getName());
+
+    Optional<EnumDeclaration> en = res.getInnerClasses().get(0).getEnumByName("T");
+    assertTrue(en.isPresent());
+  }
+
   @Test
   void testArrayOfObjects() {
     // Arrange
@@ -1087,4 +1118,27 @@ void testExistingJavaTypeObject() {
     assertEquals("org.test.ExistingJavaType", obj.getType());
     assertEquals(0, res.getTopLevelClasses().size());
   }
+
+  @Test
+  void testExistingJavaTypeEnum() {
+    // Arrange
+    Config config = Config.builder()
+        .existingJavaTypes(Collections.singletonMap("v1alpha1.E", "org.test.ExistingJavaEnum")).build();
+    JEnum obj = new JEnum(
+        "v1alpha1",
+        "E",
+        JAVA_LANG_STRING,
+        List.of(),
+        config,
+        null,
+        Boolean.FALSE,
+        null);
+
+    // Act
+    GeneratorResult res = obj.generateJava();
+
+    // Assert
+    assertEquals("org.test.ExistingJavaEnum", obj.getType());
+    assertEquals(0, res.getTopLevelClasses().size());
+  }
 }

java-generator/it/src/it/existing-java-types/pom.xml

@@ -72,9 +72,14 @@
           <source>src/main/resources/existing-java-type-crd.yml</source>
           <generatedAnnotations>false</generatedAnnotations>
           <existingJavaTypes>
+            <!-- Java Class -->
             <com.example.v1.existingjavatypespec.Affinity>
               io.fabric8.kubernetes.api.model.Affinity
             </com.example.v1.existingjavatypespec.Affinity>
+            <!-- Java Enum -->
+            <com.example.v1.existingjavatypespec.DeletionPropagation>
+              io.fabric8.kubernetes.api.model.DeletionPropagation
+            </com.example.v1.existingjavatypespec.DeletionPropagation>
           </existingJavaTypes>
         </configuration>
       </plugin>

java-generator/it/src/it/existing-java-types/src/main/java/io/fabric8/test/ExistingJavaTypes.java

@@ -17,10 +17,12 @@
 
 import com.example.v1.ExistingJavaTypeSpec;
 import io.fabric8.kubernetes.api.model.Affinity;
+import io.fabric8.kubernetes.api.model.DeletionPropagation;
 
 public class ExistingJavaTypes {
   public void example() {
     ExistingJavaTypeSpec existingJavaTypeSpec = new ExistingJavaTypeSpec();
     existingJavaTypeSpec.setAffinity(new Affinity());
+    existingJavaTypeSpec.setDeletionPropagation(DeletionPropagation.ORPHAN);
   }
 }

java-generator/it/src/it/existing-java-types/src/main/resources/existing-java-type-crd.yml

@@ -37,3 +37,6 @@ spec:
               properties:
                 affinity:
                   type: object
+                deletionPropagation:
+                  type: string
+                  enum: [ "Orphan" ]