platform/lang-api/src/com/intellij/lang/folding/FoldingBuilderEx.java

   1 /*
   2  * Copyright 2000-2009 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.folding;
  18
  19 import com.intellij.lang.ASTNode;
  20 import com.intellij.openapi.editor.Document;
  21 import com.intellij.psi.PsiElement;
  22 import org.jetbrains.annotations.NotNull;
  23 import org.jetbrains.annotations.Nullable;
  24
  25 /**
  26  * Allows a custom language plugin to define rules for folding code in the language handled
  27  * by the plugin.
  28  *
  29  * @author max
  30  * @see com.intellij.lang.folding.LanguageFolding#forLanguage(com.intellij.lang.Language)
  31  */
  32
  33 public abstract class FoldingBuilderEx implements FoldingBuilder {
  34   /**
  35    * Builds the folding regions for the specified node in the AST tree and its children.
  36    *
  37    * @param root     the element for which folding is requested.
  38    * @param document the document for which folding is built. Can be used to retrieve line
  39    *                 numbers for folding regions.
  40    * @param quick    whether the result should be providen as soon as possible. Is true, when
  41    *                 an editor is opened and we need to auto-fold something immediately, like Java imports.
  42    *                 If true, one should perform no reference resolving and avoid complex checks if possible.
  43    * @return the array of folding descriptors.
  44    */
  45   @NotNull
  46   public abstract FoldingDescriptor[] buildFoldRegions(@NotNull PsiElement root, @NotNull Document document, boolean quick);
  47
  48   @NotNull
  49   public FoldingDescriptor[] buildFoldRegions(@NotNull ASTNode node, @NotNull Document document) {
  50     return buildFoldRegions(node.getPsi(), document, false);
  51   }
  52
  53   /**
  54    * Returns the text which is displayed in the editor for the folding region related to the
  55    * specified node when the folding region is collapsed.
  56    *
  57    * @param node the node for which the placeholder text is requested.
  58    * @return the placeholder text.
  59    */
  60   @Nullable
  61   public abstract String getPlaceholderText(@NotNull ASTNode node);
  62
  63   /**
  64    * Returns the default collapsed state for the folding region related to the specified node.
  65    *
  66    * @param node the node for which the collapsed state is requested.
  67    * @return true if the region is collapsed by default, false otherwise.
  68    */
  69   public abstract boolean isCollapsedByDefault(@NotNull ASTNode node);
  70 }