lang-impl/src/com/intellij/psi/impl/source/CharTableImpl.java

   1 package com.intellij.psi.impl.source;
   2
   3 import com.intellij.util.CharTable;
   4 import com.intellij.util.text.CharArrayUtil;
   5 import com.intellij.util.text.CharSequenceHashingStrategy;
   6 import gnu.trove.THashSet;
   7
   8 /**
   9  * @author max
  10  */
  11 public class CharTableImpl implements CharTable {
  12   private final static int INTERN_THRESHOLD = 40; // 40 or more characters long tokens won't be interned.
  13   private final static CharSequenceHashingStrategy HASHER = new CharSequenceHashingStrategy();
  14   private final static MyTHashSet staticEntries = new MyTHashSet();
  15   private final MyTHashSet entries = new MyTHashSet();
  16
  17   public CharSequence intern(final CharSequence text) {
  18     if (text.length() > INTERN_THRESHOLD) return createSequence(text);
  19     int idx;
  20
  21     synchronized(staticEntries) {
  22       idx = staticEntries.index(text);
  23       if (idx >= 0) {
  24         //noinspection NonPrivateFieldAccessedInSynchronizedContext
  25         return staticEntries.get(idx);
  26       }
  27     }
  28
  29     synchronized(this) {
  30       idx = entries.index(text);
  31       if (idx >= 0) {
  32         //noinspection NonPrivateFieldAccessedInSynchronizedContext
  33         return entries.get(idx);
  34       }
  35
  36       // We need to create separate string just to prevent referencing all character data when original is string or char sequence over string
  37       final CharSequence entry = createSequence(text);
  38       boolean added = entries.add(entry);
  39       assert added;
  40
  41       return entry;
  42     }
  43   }
  44
  45   public CharSequence intern(CharSequence baseText, int startOffset, int endOffset) {
  46     if (endOffset - startOffset == baseText.length()) return baseText.toString();
  47     return intern(baseText.subSequence(startOffset, endOffset));
  48   }
  49
  50   private static CharSequence createSequence(final CharSequence text) {
  51     final char[] buf = new char[text.length()];
  52     CharArrayUtil.getChars(text, buf, 0);
  53     return StringFactory.createStringFromConstantArray(buf);
  54   }
  55
  56   public static void staticIntern(final String text) {
  57     synchronized(staticEntries) {
  58       staticEntries.add(text);
  59     }
  60   }
  61
  62   private final static class MyTHashSet extends THashSet<CharSequence> {
  63     public MyTHashSet() {
  64       super(10, 0.9f, CharTableImpl.HASHER);
  65     }
  66
  67     public int index(final CharSequence obj) {
  68       return super.index(obj);
  69     }
  70
  71     public CharSequence get(int index) {
  72       return (CharSequence)_set[index];
  73     }
  74   }
  75
  76   static {
  77     CharTableImpl.staticIntern("==" );
  78     CharTableImpl.staticIntern("!=" );
  79     CharTableImpl.staticIntern("||" );
  80     CharTableImpl.staticIntern("++" );
  81     CharTableImpl.staticIntern("--" );
  82
  83     CharTableImpl.staticIntern("<" );
  84     CharTableImpl.staticIntern("<=" );
  85     CharTableImpl.staticIntern("<<=" );
  86     CharTableImpl.staticIntern("<<" );
  87     CharTableImpl.staticIntern(">" );
  88     CharTableImpl.staticIntern("&" );
  89     CharTableImpl.staticIntern("&&" );
  90
  91     CharTableImpl.staticIntern("+=" );
  92     CharTableImpl.staticIntern("-=" );
  93     CharTableImpl.staticIntern("*=" );
  94     CharTableImpl.staticIntern("/=" );
  95     CharTableImpl.staticIntern("&=" );
  96     CharTableImpl.staticIntern("|=" );
  97     CharTableImpl.staticIntern("^=" );
  98     CharTableImpl.staticIntern("%=" );
  99
 100     CharTableImpl.staticIntern("("   );
 101     CharTableImpl.staticIntern(")"   );
 102     CharTableImpl.staticIntern("{"   );
 103     CharTableImpl.staticIntern("}"   );
 104     CharTableImpl.staticIntern("["   );
 105     CharTableImpl.staticIntern("]"   );
 106     CharTableImpl.staticIntern(";"   );
 107     CharTableImpl.staticIntern(","   );
 108     CharTableImpl.staticIntern("..." );
 109     CharTableImpl.staticIntern("."   );
 110
 111     CharTableImpl.staticIntern("=" );
 112     CharTableImpl.staticIntern("!" );
 113     CharTableImpl.staticIntern("~" );
 114     CharTableImpl.staticIntern("?" );
 115     CharTableImpl.staticIntern(":" );
 116     CharTableImpl.staticIntern("+" );
 117     CharTableImpl.staticIntern("-" );
 118     CharTableImpl.staticIntern("*" );
 119     CharTableImpl.staticIntern("/" );
 120     CharTableImpl.staticIntern("|" );
 121     CharTableImpl.staticIntern("^" );
 122     CharTableImpl.staticIntern("%" );
 123     CharTableImpl.staticIntern("@" );
 124
 125     CharTableImpl.staticIntern(" " );
 126     CharTableImpl.staticIntern("\n" );
 127     CharTableImpl.staticIntern("\n  " );
 128     CharTableImpl.staticIntern("\n    " );
 129     CharTableImpl.staticIntern("\n      " );
 130     CharTableImpl.staticIntern("\n        " );
 131     CharTableImpl.staticIntern("\n          " );
 132     CharTableImpl.staticIntern("\n            " );
 133     CharTableImpl.staticIntern("\n              " );
 134     CharTableImpl.staticIntern("\n                " );
 135
 136     CharTableImpl.staticIntern("<");
 137     CharTableImpl.staticIntern(">");
 138     CharTableImpl.staticIntern("</");
 139     CharTableImpl.staticIntern("/>");
 140     CharTableImpl.staticIntern("\"");
 141     CharTableImpl.staticIntern("\'");
 142     CharTableImpl.staticIntern("<![CDATA[");
 143     CharTableImpl.staticIntern("]]>");
 144     CharTableImpl.staticIntern("<!--");
 145     CharTableImpl.staticIntern("-->");
 146     CharTableImpl.staticIntern("<!DOCTYPE");
 147     CharTableImpl.staticIntern("SYSTEM");
 148     CharTableImpl.staticIntern("PUBLIC");
 149     CharTableImpl.staticIntern("<?");
 150     CharTableImpl.staticIntern("?>");
 151
 152     CharTableImpl.staticIntern("<%");
 153     CharTableImpl.staticIntern("%>");
 154     CharTableImpl.staticIntern("<%=");
 155     CharTableImpl.staticIntern("<%@");
 156     CharTableImpl.staticIntern("${");
 157     CharTableImpl.staticIntern("");
 158   }
 159 }