lang-impl/src/com/intellij/lang/pratt/MutableMarker.java

   1 /*
   2  * Copyright (c) 2000-2005 by JetBrains s.r.o. All Rights Reserved.
   3  * Use is subject to license terms.
   4  */
   5 package com.intellij.lang.pratt;
   6
   7 import com.intellij.lang.PsiBuilder;
   8 import com.intellij.psi.tree.IElementType;
   9
  10 import java.util.LinkedList;
  11
  12 /**
  13  * @author peter
  14  */
  15 public class MutableMarker {
  16   private final PsiBuilder.Marker myStartMarker;
  17   private IElementType myResultType;
  18   private int myInitialPathLength;
  19   private LinkedList<IElementType> myPath;
  20   private boolean myFinished;
  21
  22   public MutableMarker(final LinkedList<IElementType> path, final PsiBuilder.Marker startMarker, final int initialPathLength) {
  23     myPath = path;
  24     myStartMarker = startMarker;
  25     myInitialPathLength = initialPathLength;
  26   }
  27
  28   public MutableMarker setResultType(final IElementType resultType) {
  29     myResultType = resultType;
  30     return this;
  31   }
  32
  33   public IElementType getResultType() {
  34     return myResultType;
  35   }
  36
  37   public void finish() {
  38     assert !myFinished;
  39     myFinished = true;
  40
  41     if (myResultType == null) {
  42       myStartMarker.drop();
  43     } else {
  44       myStartMarker.done(myResultType);
  45       restorePath();
  46       myPath.addLast(myResultType);
  47     }
  48   }
  49
  50   private void restorePath() {
  51     while (myPath.size() > myInitialPathLength) {
  52       myPath.removeLast();
  53     }
  54   }
  55
  56   public MutableMarker precede() {
  57     return new MutableMarker(myPath, myStartMarker.precede(), myInitialPathLength);
  58   }
  59
  60   public void finish(final IElementType type) {
  61     setResultType(type);
  62     finish();
  63   }
  64
  65   public void drop() {
  66     assert !myFinished;
  67     myFinished = true;
  68     myStartMarker.drop();
  69   }
  70
  71   public void rollback() {
  72     assert !myFinished;
  73     myFinished = true;
  74     restorePath();
  75     myStartMarker.rollbackTo();
  76   }
  77
  78   public void error(final String message) {
  79     assert !myFinished;
  80     myFinished = true;
  81     myStartMarker.error(message);
  82   }
  83 }