platform/core-api/src/com/intellij/psi/FileContextProvider.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 com.intellij.psi;

import com.intellij.openapi.extensions.ExtensionPointName;
import com.intellij.openapi.extensions.Extensions;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.util.Collection;

/**
 * @author Dmitry Avdeev
 */
public abstract class FileContextProvider {

  public static final ExtensionPointName<FileContextProvider> EP_NAME = new ExtensionPointName<FileContextProvider>("com.intellij.fileContextProvider");

  @Nullable
  public static FileContextProvider getProvider(@NotNull final PsiFile file) {
    for (FileContextProvider provider: Extensions.getExtensions(EP_NAME, file.getProject())) {
      if (provider.isAvailable(file)) {
        return provider;
      }
    }
    return null;
  }

  protected abstract boolean isAvailable(final PsiFile file);

  @NotNull
  public abstract Collection<PsiFileSystemItem> getContextFolders(final PsiFile file);

  @Nullable
  public abstract PsiFile getContextFile(final PsiFile file);
}