JavaFxEventHandlerReferenceProvider.java

/*
 * Copyright 2000-2013 JetBrains s.r.o.
 *
 * Licensed 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.jetbrains.plugins.javaFX.fxml.refs;

import com.intellij.openapi.diagnostic.Logger;
import com.intellij.psi.PsiClass;
import com.intellij.psi.PsiMethod;
import com.intellij.psi.PsiReference;
import com.intellij.psi.impl.source.resolve.reference.impl.PsiMultiReference;
import com.intellij.psi.xml.XmlAttribute;
import com.intellij.psi.xml.XmlAttributeValue;
import com.intellij.psi.xml.XmlFile;
import com.intellij.psi.xml.XmlTag;
import com.intellij.util.ProcessingContext;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.plugins.javaFX.fxml.FxmlConstants;
import org.jetbrains.plugins.javaFX.fxml.JavaFxPsiUtil;

import java.util.Arrays;

class JavaFxEventHandlerReferenceProvider extends JavaFxControllerBasedReferenceProvider {
  private static final Logger LOG = Logger.getInstance(JavaFxEventHandlerReferenceProvider.class);

  @Override
  protected PsiReference[] getReferencesByElement(@NotNull PsiClass controllerClass,
                                                  XmlAttributeValue xmlAttributeValue,
                                                  ProcessingContext context) {
    final String attValueString = xmlAttributeValue.getValue();
    LOG.assertTrue(attValueString.startsWith("#"));

    final XmlAttribute attribute = (XmlAttribute)xmlAttributeValue.getParent();
    if (attribute == null || !JavaFxPsiUtil.isEventHandlerProperty(attribute)) return PsiReference.EMPTY_ARRAY;
    final String eventHandlerName = attValueString.substring(1);
    final PsiMethod[] methods = controllerClass.findMethodsByName(eventHandlerName, true);

    final PsiReference[] references = Arrays.stream(methods)
      .filter(psiMethod -> JavaFxEventHandlerReference.isHandlerMethodSignature(psiMethod, controllerClass))
      .map(psiMethod -> new JavaFxEventHandlerReference(xmlAttributeValue, psiMethod, controllerClass))
      .toArray(PsiReference.ARRAY_FACTORY::create);

    if (references.length == 1) {
      return references;
    }
    if (references.length > 1) {
      return new PsiReference[]{new PsiMultiReference(references, xmlAttributeValue)};
    }

    if (references.length == 0) {
      final XmlTag rootTag = ((XmlFile)xmlAttributeValue.getContainingFile()).getRootTag();
      if (rootTag == null || FxmlConstants.FX_ROOT.equals(rootTag.getName())) {
        return PsiReference.EMPTY_ARRAY;
      }
    }
    return new PsiReference[]{new JavaFxEventHandlerReference(xmlAttributeValue, null, controllerClass)};
  }
}