java/java-impl/src/com/intellij/codeInsight/navigation/actions/JavaTypeDeclarationProvider.java

/*
 * Copyright 2000-2014 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 com.intellij.codeInsight.navigation.actions;

import com.intellij.codeInsight.TargetElementUtilBase;
import com.intellij.openapi.editor.Editor;
import com.intellij.psi.*;
import com.intellij.psi.util.PsiUtil;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

/**
 * @author yole
 */
public class JavaTypeDeclarationProvider implements TypeDeclarationPlaceAwareProvider {
  @Override
  public PsiElement[] getSymbolTypeDeclarations(@NotNull PsiElement symbol) {
    return getSymbolTypeDeclarations(symbol, null, -1);
  }

  @Nullable
  @Override
  public PsiElement[] getSymbolTypeDeclarations(@NotNull PsiElement targetElement, Editor editor, int offset) {
    PsiType type;
    if (targetElement instanceof PsiVariable){
      type = ((PsiVariable)targetElement).getType();
    }
    else if (targetElement instanceof PsiMethod){
      type = ((PsiMethod)targetElement).getReturnType();
    }
    else{
      return null;
    }
    if (type == null) return null;
    if (editor != null) {
      final PsiReference reference = TargetElementUtilBase.findReference(editor, offset);
      if (reference instanceof PsiJavaReference) {
        final JavaResolveResult resolveResult = ((PsiJavaReference)reference).advancedResolve(true);
        type = resolveResult.getSubstitutor().substitute(type);
      }
    }
    PsiClass psiClass = PsiUtil.resolveClassInType(type);
    return psiClass == null ? null : new PsiElement[] {psiClass};
  }
}