source/com/intellij/lexer/PrefixSuffixStripperLexer.java

   1 /*
   2  * @author max
   3  */
   4 package com.intellij.lexer;
   5
   6 import com.intellij.psi.tree.IElementType;
   7 import com.intellij.util.text.CharArrayUtil;
   8 import com.intellij.util.text.CharArrayCharSequence;
   9
  10 public class PrefixSuffixStripperLexer extends LexerBase {
  11   private CharSequence myBuffer;
  12   private char[] myBufferArray;
  13   private int myTokenStart;
  14   private int myTokenEnd;
  15   private IElementType myTokenType;
  16   private int myState;
  17   private int myBufferEnd;
  18   private String myPrefix;
  19   private IElementType myPrefixType;
  20   private String mySuffix;
  21   private IElementType myMiddleTokenType;
  22   private IElementType mySuffixType;
  23
  24   public PrefixSuffixStripperLexer(final String prefix,
  25                                    final IElementType prefixType,
  26                                    final String suffix,
  27                                    final IElementType suffixType,
  28                                    final IElementType middleTokenType) {
  29     mySuffixType = suffixType;
  30     myMiddleTokenType = middleTokenType;
  31     mySuffix = suffix;
  32     myPrefixType = prefixType;
  33     myPrefix = prefix;
  34   }
  35
  36   public void start(char[] buffer, int startOffset, int endOffset, int initialState) {
  37     start(new CharArrayCharSequence(buffer),startOffset, endOffset, initialState);
  38   }
  39
  40   public void start(CharSequence buffer, int startOffset, int endOffset, int initialState) {
  41     myBuffer = buffer;
  42     myBufferArray = CharArrayUtil.fromSequenceWithoutCopying(buffer);
  43     myTokenStart = startOffset;
  44     myTokenEnd = startOffset;
  45     myTokenType = null;
  46     myState = initialState;
  47     myBufferEnd = endOffset;
  48   }
  49
  50   public IElementType getTokenType() {
  51     locateToken();
  52     return myTokenType;
  53   }
  54
  55   public int getTokenStart() {
  56     locateToken();
  57     return myTokenStart;
  58   }
  59
  60   public int getTokenEnd() {
  61     locateToken();
  62     return myTokenEnd;
  63   }
  64
  65   public int getState() {
  66     return myState;
  67   }
  68
  69   public int getBufferEnd() {
  70     return myBufferEnd;
  71   }
  72
  73   public char[] getBuffer() {
  74     return CharArrayUtil.fromSequence(myBuffer);
  75   }
  76
  77   public CharSequence getBufferSequence() {
  78     return myBuffer;
  79   }
  80
  81   public void advance() {
  82     myTokenType = null;
  83   }
  84
  85   private void locateToken() {
  86     if (myTokenType != null || myState == 3) return;
  87
  88     if (myState == 0) {
  89       myTokenEnd = myTokenStart + myPrefix.length();
  90       myTokenType = myPrefixType;
  91       myState = myTokenEnd < myBufferEnd ? 1 : 3;
  92       return;
  93     }
  94
  95     if (myState == 1) {
  96       myTokenStart = myTokenEnd;
  97       final int suffixStart = myBufferEnd - mySuffix.length();
  98       myTokenType = myMiddleTokenType;
  99       if ( (myBufferArray != null && CharArrayUtil.regionMatches(myBufferArray, suffixStart, myBufferEnd, mySuffix)) ||
 100            (myBufferArray == null && CharArrayUtil.regionMatches(myBuffer, suffixStart, myBufferEnd, mySuffix))
 101          ) {
 102         myTokenEnd = suffixStart;
 103         if (myTokenStart < myTokenEnd) {
 104           myState = 2;
 105         }
 106         else {
 107           myState = 3;
 108           myTokenType = mySuffixType;
 109           myTokenEnd = myBufferEnd;
 110         }
 111       }
 112       else {
 113         myTokenEnd = myBufferEnd;
 114         myState = 3;
 115       }
 116
 117       return;
 118     }
 119
 120     if (myState == 2) {
 121       myTokenStart = myTokenEnd;
 122       myTokenEnd = myBufferEnd;
 123       myTokenType = mySuffixType;
 124       myState = 3;
 125     }
 126   }
 127 }