[ui] XPath AutoComplete

pmd-ui/src/main/java/net/sourceforge/pmd/util/fxdesigner/XPathPanelController.java

@@ -7,6 +7,7 @@
 import java.io.IOException;
 import java.net.URL;
 import java.time.Duration;
+import java.util.ArrayList;
 import java.util.Collections;
 import java.util.List;
 import java.util.Objects;
@@ -28,6 +29,7 @@
 import net.sourceforge.pmd.util.fxdesigner.model.ObservableXPathRuleBuilder;
 import net.sourceforge.pmd.util.fxdesigner.model.XPathEvaluationException;
 import net.sourceforge.pmd.util.fxdesigner.model.XPathEvaluator;
+import net.sourceforge.pmd.util.fxdesigner.model.XPathSuggestions;
 import net.sourceforge.pmd.util.fxdesigner.util.DesignerUtil;
 import net.sourceforge.pmd.util.fxdesigner.util.beans.SettingsOwner;
 import net.sourceforge.pmd.util.fxdesigner.util.beans.SettingsPersistenceUtil.PersistentProperty;
@@ -50,6 +52,8 @@
 import javafx.scene.control.MenuItem;
 import javafx.scene.control.TextArea;
 import javafx.scene.control.TitledPane;
+import javafx.scene.input.KeyCode;
+import javafx.scene.input.KeyEvent;
 import javafx.scene.input.MouseButton;
 import javafx.scene.input.MouseEvent;
 import javafx.stage.Modality;
@@ -84,6 +88,8 @@ public class XPathPanelController implements Initializable, SettingsOwner {
     @SuppressWarnings("PMD.SingularField")
     private ChoiceBox<String> xpathVersionChoiceBox;
 
+    private ContextMenu autoCompletePopup;
+
 
     public XPathPanelController(DesignerRoot owner, MainDesignerController mainController) {
         this.designerRoot = owner;
@@ -112,9 +118,66 @@ public void initialize(URL location, ResourceBundle resources) {
                            // Reevaluate XPath anytime the expression or the XPath version changes
                            .or(xpathVersionProperty().changes())
                            .subscribe(tick -> parent.refreshXPathResults());
+
+        xpathExpressionArea.plainTextChanges()
+                           .filter(t -> (t.getInserted().matches("[a-zA-Z]")) || t.getInserted().matches("/"))
+                           .subscribe(t -> {
+                               try {
+                                   if (t.getInserted().equals("/")) {
+                                       autoComplete(xpathExpressionArea.getText().substring(xpathExpressionArea.getText().indexOf("/")));
+                                   } else if (!t.getInserted().equals("/")) {
+                                       autoComplete(xpathExpressionArea.getText().substring(xpathExpressionArea.getText().lastIndexOf("/")));
+                                   }
+                               } catch (IOException e) {
+                                   e.printStackTrace();
+                               } catch (ClassNotFoundException e) {
+                                   e.printStackTrace();
+                               }
+                           });
+    }
+
+    private void autoComplete(String s) throws IOException, ClassNotFoundException {
+
+        autoCompletePopup = new ContextMenu();
+        List<MenuItem> resultToDisplay = new ArrayList<>();
+
+        String language = parent.getLanguageVersion().getName().replaceAll("[0-9]", "").replaceAll("//s", "").toLowerCase().trim();
+        XPathSuggestions xPathSuggestions = new XPathSuggestions("net.sourceforge.pmd.lang." + language + ".ast");
+
+        List<String> suggestions = xPathSuggestions.getXPathSuggestions();
+
+        for (String s1 : suggestions) {
+            if (s1.contains(s.replace("/", "").trim())) {
+                MenuItem m = new MenuItem(s1);
+                if (!resultToDisplay.contains(m)) {
+                    resultToDisplay.add(m);
+                }
+            }
+        }
+
+        //TODO: Work on the implementation of the Result to be selected and added to the Code Area
+        autoCompletePopup.getItems().addAll(resultToDisplay);
+
+        if (xpathExpressionArea.getText().length() > 0) {
+
+            xpathExpressionArea.addEventHandler(KeyEvent.KEY_TYPED, t -> {
+                if (t.getCode() != KeyCode.ESCAPE) {
+                    xpathExpressionArea.setContextMenu(autoCompletePopup);
+                }
+            });
+
+            xpathExpressionArea.addEventHandler(KeyEvent.KEY_PRESSED, t -> {
+                if (t.getCode() == KeyCode.ESCAPE) {
+                    autoCompletePopup.hide();
+                }
+            });
+
+
+        }
     }
 
 
+
     private void initGenerateXPathFromStackTrace() {
 
         ContextMenu menu = new ContextMenu();

pmd-ui/src/main/java/net/sourceforge/pmd/util/fxdesigner/model/XPathSuggestions.java

@@ -0,0 +1,97 @@
+/**
+ * BSD-style license; for more info see http://pmd.sourceforge.net/license.html
+ */
+
+package net.sourceforge.pmd.util.fxdesigner.model;
+
+import java.io.File;
+import java.io.IOException;
+import java.net.URL;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Enumeration;
+import java.util.List;
+
+
+public class XPathSuggestions {
+    private List<String> xPathSuggestions = new ArrayList<>();
+    String packagename;
+
+    public XPathSuggestions(String packageName) {
+        this.packagename = packageName;
+    }
+
+
+    public List<String> getXPathSuggestions() throws IOException, ClassNotFoundException {
+        return evaluateXpathSuggestions(createList(getClasses(packagename)));
+    }
+
+    private List<String> createList(Class[] classArray) {
+        List<Class> fileNameList = Arrays.asList(classArray);
+        List<String> foo = new ArrayList<>();
+
+        for (Class c : fileNameList) {
+
+            if (c.getName().contains("AST")) {
+                foo.add(c.getName());
+            }
+        }
+
+        return foo;
+    }
+
+    private static Class[] getClasses(String packageName) throws ClassNotFoundException, IOException {
+
+        ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
+        assert classLoader != null;
+
+        String path = packageName.replace('.', '/');
+        Enumeration<URL> resources = classLoader.getResources(path);
+
+        List<File> dirs = new ArrayList<>();
+
+        while (resources.hasMoreElements()) {
+            URL resource = resources.nextElement();
+            dirs.add(new File(resource.getFile()));
+        }
+
+        ArrayList<Class> classes = new ArrayList<>();
+
+        for (File directory : dirs) {
+            classes.addAll(findClasses(directory, packageName));
+        }
+
+        return classes.toArray(new Class[classes.size()]);
+    }
+
+
+    private static List<Class> findClasses(File directory, String packageName) throws ClassNotFoundException {
+
+        List<Class> classes = new ArrayList<>();
+        if (!directory.exists()) {
+            return classes;
+        }
+
+        File[] files = directory.listFiles();
+        for (File file : files) {
+            if (file.isDirectory()) {
+                assert !file.getName().contains(".");
+                classes.addAll(findClasses(file, packageName + "." + file.getName()));
+            } else if (file.getName().endsWith(".class")) {
+                classes.add(Class.forName(packageName + "." + file.getName().substring(0, file.getName().length() - 6)));
+            }
+        }
+
+        return classes;
+    }
+
+    private List<String> evaluateXpathSuggestions(List<String> fileNameList) {
+        for (String s : fileNameList) {
+            //Check if the package name should be hardcoded
+            xPathSuggestions.add(s.replace("AST", "").replace(".java", "").replace("net.sourceforge.pmd.lang.ast" + ".", ""));
+        }
+        return xPathSuggestions;
+    }
+
+
+}