openide/java/java-psi-impl/src/com/intellij/psi/stub/JavaStubImplUtil.java

/*
 * Copyright 2000-2017 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.psi.stub;

import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiMethod;
import com.intellij.psi.impl.source.PsiFileImpl;
import com.intellij.psi.impl.source.PsiMethodImpl;
import com.intellij.psi.impl.source.tree.JavaElementType;
import com.intellij.psi.stubs.StubElement;
import com.intellij.psi.stubs.StubTree;
import com.intellij.util.ArrayUtil;

public class JavaStubImplUtil {
  public static int getMethodStubIndex(PsiMethod method) {
    if (!(method instanceof PsiMethodImpl)) return -1;
    PsiFileImpl file = (PsiFileImpl)method.getContainingFile();
    if (file.getElementTypeForStubBuilder() == null) return -1;
    StubTree stubTree = file.getStubTree();
    if (stubTree == null) {
      stubTree = file.calcStubTree();
    }

    PsiElement[] stubs = stubTree
      .getPlainList()
      .stream()
      .filter(e -> e.getStubType() == JavaElementType.METHOD)
      .map(StubElement::getPsi)
      .toArray(PsiElement[]::new);
    return ArrayUtil.indexOf(stubs, method);
  }
}