lang-api/src/com/intellij/lang/ImportOptimizer.java

   1 /*
   2  * Copyright 2000-2007 JetBrains s.r.o.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package com.intellij.lang;
  18
  19 import com.intellij.psi.PsiFile;
  20 import org.jetbrains.annotations.NotNull;
  21
  22 /**
  23  * Implementors of the interface encapsulate optimize imports process for the language.
  24  * @author max
  25  * @see ImportOptimizer2
  26  */
  27 public interface ImportOptimizer {
  28   /**
  29    * Implementors of the method are expected to perform all necessary calculations synchronously and return a <code>Runnable</code>,
  30    * which performs modifications based on preprocessing results.
  31    * processFile() is guaranteed to run with {@link com.intellij.openapi.application.Application#runReadAction(Runnable)} priviledges and
  32    * the Runnable returned is guaranteed to run with {@link com.intellij.openapi.application.Application#runWriteAction(Runnable)} privileges.
  33    *
  34    * One can theoretically delay all the calculation until Runnable is called but this code will be executed in Swing thread thus
  35    * lenghty calculations may block user interface for some significant time.
  36    *
  37    * @param file to optimize an imports in. It's guaranteed to have a language this <code>ImportOptimizer</code> have been
  38    * issued from.
  39    * @return a <code>java.lang.Runnable</code> object, which being called will replace original file imports with optimized version.
  40    */
  41   @NotNull
  42   Runnable processFile(PsiFile file);
  43 }