java/java-psi-impl/src/com/intellij/psi/impl/compiled/ClassFileStubBuilder.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.psi.impl.compiled;

import com.intellij.openapi.diagnostic.Logger;
import com.intellij.openapi.extensions.Extensions;
import com.intellij.openapi.project.Project;
import com.intellij.openapi.vfs.VirtualFile;
import com.intellij.psi.compiled.ClassFileDecompilers;
import com.intellij.psi.stubs.BinaryFileStubBuilder;
import com.intellij.psi.stubs.PsiFileStub;
import com.intellij.psi.stubs.StubElement;
import com.intellij.util.cls.ClsFormatException;
import com.intellij.util.containers.ContainerUtil;
import com.intellij.util.indexing.FileContent;
import org.jetbrains.annotations.NotNull;

import java.util.Collections;
import java.util.Comparator;
import java.util.List;

import static com.intellij.psi.compiled.ClassFileDecompilers.Full;

/**
 * @author max
 */
public class ClassFileStubBuilder implements BinaryFileStubBuilder {
  private static final Logger LOG = Logger.getInstance("#com.intellij.psi.impl.compiled.ClassFileStubBuilder");

  public static final int STUB_VERSION = 12;

  @Override
  public boolean acceptsFile(@NotNull VirtualFile file) {
    return true;
  }

  @SuppressWarnings("deprecation")
  @Override
  public StubElement buildStubTree(@NotNull FileContent fileContent) {
    VirtualFile file = fileContent.getFile();
    byte[] content = fileContent.getContent();

    try {
      ClassFileDecompilers.Decompiler decompiler = ClassFileDecompilers.find(file);
      if (decompiler instanceof Full) {
        return ((Full)decompiler).getStubBuilder().buildFileStub(fileContent);
      }
    }
    catch (ClsFormatException e) {
      LOG.debug(e);
    }

    try {
      Project project = fileContent.getProject();
      for (ClsStubBuilderFactory factory : Extensions.getExtensions(ClsStubBuilderFactory.EP_NAME)) {
        if (!factory.isInnerClass(file) && factory.canBeProcessed(file, content)) {
          PsiFileStub stub = factory.buildFileStub(file, content, project);
          if (stub != null) return stub;
        }
      }
    }
    catch (ClsFormatException e) {
      LOG.debug(e);
    }

    try {
      PsiFileStub<?> stub = ClsFileImpl.buildFileStub(file, content);
      if (stub == null && !fileContent.getFileName().contains("$")) {
        LOG.info("No stub built for file " + fileContent);
      }
      return stub;
    }
    catch (ClsFormatException e) {
      LOG.debug(e);
    }

    return null;
  }

  private static final Comparator<Object> CLASS_NAME_COMPARATOR = new Comparator<Object>() {
    @Override
    public int compare(Object o1, Object o2) {
      return o1.getClass().getName().compareTo(o2.getClass().getName());
    }
  };

  @SuppressWarnings("deprecation")
  @Override
  public int getStubVersion() {
    int version = STUB_VERSION;

    List<ClassFileDecompilers.Decompiler> decompilers = ContainerUtil.newArrayList(ClassFileDecompilers.EP_NAME.getExtensions());
    Collections.sort(decompilers, CLASS_NAME_COMPARATOR);
    for (ClassFileDecompilers.Decompiler decompiler : decompilers) {
      if (decompiler instanceof Full) {
        version = version * 31 + ((Full)decompiler).getStubBuilder().getStubVersion() + decompiler.getClass().getName().hashCode();
      }
    }

    List<ClsStubBuilderFactory> factories = ContainerUtil.newArrayList(Extensions.getExtensions(ClsStubBuilderFactory.EP_NAME));
    Collections.sort(factories, CLASS_NAME_COMPARATOR);
    for (ClsStubBuilderFactory factory : factories) {
      version = version * 31 + factory.getStubVersion() + factory.getClass().getName().hashCode();
    }

    return version;
  }
}