Improve search results in treeview

Author: oowekyala

src/main/java/net/sourceforge/pmd/util/fxdesigner/util/autocomplete/matchers/StringMatchUtil.java

@@ -30,10 +30,18 @@ private StringMatchUtil() {
     /**
      * Selects the best {@link MatchResult} given a list of candidates and a query.
      *
-     * The results are useless unless you provide the {@link MatchSelector} that
-     * suits your use case.
+     * <p>The results are useless unless you provide the {@link MatchSelector} that
+     * suits your use case (limiter).
+     *
+     * @param candidates     List of stuff to sort
+     * @param matchExtractor Extracts the searchable text from an item
+     * @param limiter        Selects the best candidates, may process them further to break ties
+     * @param query          Text to search for
      */
-    public static <T> Stream<MatchResult<T>> filterResults(List<T> candidates, Function<T, String> matchExtractor, String query, MatchSelector<T> limiter) {
+    public static <T> Stream<MatchResult<T>> filterResults(List<? extends T> candidates,
+                                                           Function<? super T, String> matchExtractor,
+                                                           String query,
+                                                           MatchSelector<T> limiter) {
         if (query.length() < MIN_QUERY_LENGTH) {
             return Stream.empty();
         }

src/main/java/net/sourceforge/pmd/util/fxdesigner/util/controls/SearchableTreeView.java

@@ -43,6 +43,12 @@
 import javafx.scene.layout.StackPane;
 import javafx.stage.Popup;
 
+/**
+ *
+ * @param <T> Item type
+ * @see SearchableTreeItem
+ * @see SearchableTreeCell
+ */
 public class SearchableTreeView<T> extends TreeView<T> {
 
     public static final int MIN_QUERY_LENGTH = 1;
@@ -81,6 +87,9 @@ private SearchableTreeItem<T> getRealRoot() {
     }
 
 
+    /**
+     * Textfield for the search query.
+     */
     private void popSearchField() {
         TextField textField = new TextField();
         textField.setPrefWidth(150);
@@ -210,25 +219,27 @@ private Subscription subscribeKeyNav(int numResults, Var<Integer> curIdx, Node e
 
     }
 
-
     private List<MatchResult<SearchableTreeItem<T>>> selectMatches(String query, List<SearchableTreeItem<T>> items) {
         MatchSelector<SearchableTreeItem<T>> limiter =
             CamelCaseMatcher.<SearchableTreeItem<T>>allQueryStarts()
                 .andThen(c -> c.filter(it -> it.getScore() > 0))
                 .andThen(Stream::parallel)
+                .andThen(CamelCaseMatcher.onlyWordStarts())
                 .andThen(MatchSelector.selectBestTies());
 
         return StringMatchUtil.filterResults(items, SearchableTreeItem::getSearchableText, query, limiter)
                               .sorted(Comparator.comparingInt(res -> res.getData().getTreeIndex()))
                               .collect(Collectors.toList());
     }
 
+
     public abstract static class SearchableTreeItem<T> extends TreeItem<T> {
 
         private final Var<SearchableTreeCell<T>> treeCell = Var.newSimpleVar(null);
         private final Var<MatchResult<SearchableTreeItem<T>>> currentSearchResult = Var.newSimpleVar(null);
         private final int treeIndex;
 
+
         public SearchableTreeItem(T n, int treeIndex) {
             super(n);
             this.treeIndex = treeIndex;
@@ -244,17 +255,33 @@ public Var<SearchableTreeCell<T>> treeCellProperty() {
             return treeCell;
         }
 
+
         public Val<MatchResult<SearchableTreeItem<T>>> currentSearchResultProperty() {
             return currentSearchResult;
         }
 
+
+        /**
+         * Text used to match search queries. This must be the
+         * same text as is displayed on the cell in normal mode.
+         */
         public abstract String getSearchableText();
 
+
         public int getTreeIndex() {
             return treeIndex;
         }
     }
 
+    /**
+     * A searchable tree cell is bound both ways to a searchable
+     * tree item. It has three visual states:
+     * <ul>
+     * <li>unbound (no underlying item, not visible in tree)
+     * <li>bound with a search result (in which case it displays the styled search result)
+     * <li>bound without a search result (in which case it displays the searchable text, maybe with some styling)
+     * </ul>
+     */
     public abstract static class SearchableTreeCell<T> extends TreeCell<T> {
 
         public SearchableTreeCell() {
@@ -272,6 +299,7 @@ public SearchableTreeCell() {
                 });
         }
 
+
         protected Val<MatchResult<SearchableTreeItem<T>>> searchResultProperty() {
             return realItemProperty().flatMap(SearchableTreeItem::currentSearchResultProperty);
         }
@@ -298,12 +326,19 @@ public void updateItem(T item, boolean empty) {
             }
         }
 
+
+        /**
+         * Update just for when the item is not a search result.
+         */
         protected void setNonSearchState(SearchableTreeItem<T> realItem) {
             setGraphic(null);
-            // todo would be nicer if the treeview had colors
             setText(realItem.getSearchableText());
         }
 
+
+        /**
+         * Update for both visible states.
+         */
         public abstract void commonUpdate(T item);