Fix for add char and token filters in Luke Analysis tab (#14682)

Author: pseudo-nymous

lucene/CHANGES.txt

@@ -116,6 +116,8 @@ Bug Fixes
 * GITHUB#14654: ValueSource.fromDoubleValuesSource(dvs).getSortField() would throw errors when
   used if the DoubleValuesSource needed scores. (David Smiley)
 
+* GITHUB#14682 : Fix for add char and token filters in Luke Analysis tab. (Amir Raza)
+
 Build
 ---------------------
 * Upgrade forbiddenapis to version 3.9.  (Uwe Schindler)

lucene/luke/src/java/org/apache/lucene/luke/app/desktop/util/ListUtils.java

@@ -19,6 +19,7 @@
 
 import java.util.List;
 import java.util.function.IntFunction;
+import java.util.stream.Collectors;
 import java.util.stream.IntStream;
 import javax.swing.JList;
 import javax.swing.ListModel;
@@ -33,7 +34,7 @@ public static <T> List<T> getAllItems(JList<T> jlist) {
 
   public static <T, R> List<R> getAllItems(JList<T> jlist, IntFunction<R> mapFunc) {
     ListModel<T> model = jlist.getModel();
-    return IntStream.range(0, model.getSize()).mapToObj(mapFunc).toList();
+    return IntStream.range(0, model.getSize()).mapToObj(mapFunc).collect(Collectors.toList());
   }
 
   private ListUtils() {}

lucene/luke/src/test/org/apache/lucene/luke/app/desktop/util/TestListUtils.java

@@ -0,0 +1,37 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.lucene.luke.app.desktop.util;
+
+import java.util.Arrays;
+import java.util.List;
+import javax.swing.JList;
+import org.apache.lucene.tests.util.LuceneTestCase;
+import org.junit.Test;
+
+public class TestListUtils extends LuceneTestCase {
+
+  @Test
+  public void testGetAllItems() {
+    JList<String> list = new JList<>(new String[] {"Item 1", "Item 2"});
+    List<String> items = ListUtils.getAllItems(list);
+    assertEquals(Arrays.asList("Item 1", "Item 2"), items);
+    // test mutability
+    items.add("Item 3");
+    assertEquals(Arrays.asList("Item 1", "Item 2", "Item 3"), items);
+  }
+}