/*
* Copyright 2000-2016 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.util.gist;
import com.intellij.openapi.application.ApplicationManager;
import com.intellij.psi.PsiFile;
import com.intellij.util.NullableFunction;
import com.intellij.util.io.DataExternalizer;
import org.jetbrains.annotations.NotNull;
/**
* A helper class for working with file gists: associating persistent data with current VFS or PSI file contents.
*
* @since 171.*
* @author peter
*/
public abstract class GistManager {
@NotNull
public static GistManager getInstance() {
return ApplicationManager.getApplication().getComponent(GistManager.class);
}
/**
* Create a new {@link VirtualFileGist}.
* @param id a unique identifier of this data
* @param version should be incremented each time the {@code externalizer} or {@code calcData} logic changes.
* @param externalizer used to store the data to the disk and retrieve it
* @param calcData calculates the data by the file content when needed
* @param <Data> the type of the data to cache
* @return the gist object, where {@link VirtualFileGist#getFileData} can later be used to retrieve the cached data
*/
@NotNull
public abstract <Data> VirtualFileGist<Data> newVirtualFileGist(@NotNull String id,
int version,
@NotNull DataExternalizer<Data> externalizer,
@NotNull VirtualFileGist.GistCalculator<Data> calcData);
/**
* Create a new {@link PsiFileGist}.
* @param id a unique identifier of this data
* @param version should be incremented each time the {@code externalizer} or {@code calcData} logic changes.
* @param externalizer used to store the data to the disk and retrieve it
* @param calcData calculates the data by the file content when needed
* @param <Data> the type of the data to cache
* @return the gist object, where {@link PsiFileGist#getFileData} can later be used to retrieve the cached data
*/
@NotNull
public abstract <Data> PsiFileGist<Data> newPsiFileGist(@NotNull String id,
int version,
@NotNull DataExternalizer<Data> externalizer,
@NotNull NullableFunction<PsiFile, Data> calcData);
}