perpare code to alternative java21 variant

vocabulary-format-assertion/src/main/java/io/github/sebastiantoepfer/jsonschema/vocabulary/format/assertion/abnf/reader/ConcatenationExtractor.java

@@ -65,14 +65,12 @@ public Extractor append(final int codePoint) {
         } else if (Character.isWhitespace(codePoint)) {
             result = new ConcatenationExtractor(owner, elements, currentEndOfElementDetector);
         } else if (codePoint == SOLIDUS) {
-            final List<Element> newElements = new ArrayList<>(elements);
-            final Element element = newElements.remove(newElements.size() - 1);
             result =
-                AlternativeExtractor.of(
-                    new ConcatenationExtractor(owner, newElements, currentEndOfElementDetector),
-                    element,
-                    currentEndOfElementDetector
-                );
+                new ConcationTypeSwitch(owner, currentEndOfElementDetector, elements)
+                    .switchTo(
+                        (o, d, e) -> new ConcatenationExtractor(o, e, d),
+                        (o, d, e) -> AlternativeExtractor.of(o, e, d)
+                    );
         } else {
             result = RepetitionExtractor.of(this).append(codePoint);
         }

vocabulary-format-assertion/src/main/java/io/github/sebastiantoepfer/jsonschema/vocabulary/format/assertion/abnf/reader/ConcationTypeSwitch.java

@@ -0,0 +1,56 @@
+/*
+ * The MIT License
+ *
+ * Copyright 2023 sebastian.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package io.github.sebastiantoepfer.jsonschema.vocabulary.format.assertion.abnf.reader;
+
+import io.github.sebastiantoepfer.jsonschema.vocabulary.format.assertion.abnf.element.Element;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Objects;
+
+final class ConcationTypeSwitch {
+
+    private final ExtractorOwner owner;
+    private final ElementEndDetector endOfElementDetector;
+    private final List<Element> elements;
+
+    public ConcationTypeSwitch(
+        final ExtractorOwner owner,
+        final ElementEndDetector endOfElementDetector,
+        final List<Element> elements
+    ) {
+        this.owner = Objects.requireNonNull(owner);
+        this.endOfElementDetector = Objects.requireNonNull(endOfElementDetector);
+        this.elements = List.copyOf(elements);
+    }
+
+    public Extractor switchTo(final ExtractorOwnerFactory ownerFactory, final ExtractorFactory targetFactory) {
+        final List<Element> newElements = new ArrayList<>(elements);
+        final Element element = newElements.remove(newElements.size() - 1);
+        return targetFactory.create(
+            ownerFactory.create(owner, endOfElementDetector, newElements),
+            endOfElementDetector,
+            element
+        );
+    }
+}

vocabulary-format-assertion/src/main/java/io/github/sebastiantoepfer/jsonschema/vocabulary/format/assertion/abnf/reader/ExtractorFactory.java

@@ -0,0 +1,31 @@
+/*
+ * The MIT License
+ *
+ * Copyright 2023 sebastian.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package io.github.sebastiantoepfer.jsonschema.vocabulary.format.assertion.abnf.reader;
+
+import io.github.sebastiantoepfer.jsonschema.vocabulary.format.assertion.abnf.element.Element;
+
+@FunctionalInterface
+interface ExtractorFactory {
+    Extractor create(ExtractorOwner owner, ElementEndDetector currentEndOfElementDetector, Element element);
+}

vocabulary-format-assertion/src/main/java/io/github/sebastiantoepfer/jsonschema/vocabulary/format/assertion/abnf/reader/ExtractorOwnerFactory.java

@@ -0,0 +1,32 @@
+/*
+ * The MIT License
+ *
+ * Copyright 2023 sebastian.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+package io.github.sebastiantoepfer.jsonschema.vocabulary.format.assertion.abnf.reader;
+
+import io.github.sebastiantoepfer.jsonschema.vocabulary.format.assertion.abnf.element.Element;
+import java.util.List;
+
+@FunctionalInterface
+interface ExtractorOwnerFactory {
+    ExtractorOwner create(ExtractorOwner owner, ElementEndDetector currentEndOfElementDetector, List<Element> elements);
+}