refactory: added UI removed from core plugin.
[phpeclipse.git] / net.sourceforge.phpeclipse.ui / src / net / sourceforge / phpdt / internal / ui / text / CombinedWordRule.java
diff --git a/net.sourceforge.phpeclipse.ui/src/net/sourceforge/phpdt/internal/ui/text/CombinedWordRule.java b/net.sourceforge.phpeclipse.ui/src/net/sourceforge/phpdt/internal/ui/text/CombinedWordRule.java
new file mode 100644 (file)
index 0000000..dedad70
--- /dev/null
@@ -0,0 +1,408 @@
+/*******************************************************************************
+ * Copyright (c) 2000, 2003 IBM Corporation and others.
+ * All rights reserved. This program and the accompanying materials 
+ * are made available under the terms of the Common Public License v1.0
+ * which accompanies this distribution, and is available at
+ * http://www.eclipse.org/legal/cpl-v10.html
+ * 
+ * Contributors:
+ *     IBM Corporation - initial API and implementation
+ *******************************************************************************/
+package net.sourceforge.phpdt.internal.ui.text;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+
+import org.eclipse.jface.text.Assert;
+import org.eclipse.jface.text.rules.ICharacterScanner;
+import org.eclipse.jface.text.rules.IRule;
+import org.eclipse.jface.text.rules.IToken;
+import org.eclipse.jface.text.rules.IWordDetector;
+import org.eclipse.jface.text.rules.Token;
+
+/**
+ * An implementation of <code>IRule</code> capable of detecting words.
+ * <p>
+ * Word rules also allow for the association of tokens with specific words. That
+ * is, not only can the rule be used to provide tokens for exact matches, but
+ * also for the generalized notion of a word in the context in which it is used.
+ * A word rules uses a word detector to determine what a word is.
+ * </p>
+ * <p>
+ * This word rule allows a word detector to be shared among different word
+ * matchers. Its up to the word matchers to decide if a word matches and, in
+ * this a case, which token is associated with that word.
+ * </p>
+ * 
+ * @see IWordDetector
+ * @since 3.0
+ */
+public class CombinedWordRule implements IRule {
+
+       /**
+        * Word matcher, that associates matched words with tokens.
+        */
+       public static class WordMatcher {
+
+               /** The table of predefined words and token for this matcher */
+               private Map fWords = new HashMap();
+
+               /**
+                * Adds a word and the token to be returned if it is detected.
+                * 
+                * @param word
+                *            the word this rule will search for, may not be
+                *            <code>null</code>
+                * @param token
+                *            the token to be returned if the word has been found, may
+                *            not be <code>null</code>
+                */
+               public void addWord(String word, IToken token) {
+                       Assert.isNotNull(word);
+                       Assert.isNotNull(token);
+
+                       fWords.put(new CharacterBuffer(word), token);
+               }
+
+               /**
+                * Returns the token associated to the given word and the scanner state.
+                * 
+                * @param scanner
+                *            the scanner
+                * @param word
+                *            the word
+                * @return the token or <code>null</code> if none is associated by
+                *         this matcher
+                */
+               public IToken evaluate(ICharacterScanner scanner, CharacterBuffer word) {
+                       IToken token = (IToken) fWords.get(word);
+                       if (token != null)
+                               return token;
+                       return Token.UNDEFINED;
+               }
+
+               /**
+                * Removes all words.
+                */
+               public void clearWords() {
+                       fWords.clear();
+               }
+       }
+
+       /**
+        * Character buffer, mutable <b>or</b> suitable for use as key in hash
+        * maps.
+        */
+       public static class CharacterBuffer {
+
+               /** Buffer content */
+               private char[] fContent;
+
+               /** Buffer content size */
+               private int fLength = 0;
+
+               /** Is hash code cached? */
+               private boolean fIsHashCached = false;
+
+               /** The hash code */
+               private int fHashCode;
+
+               /**
+                * Initialize with the given capacity.
+                * 
+                * @param capacity
+                *            the initial capacity
+                */
+               public CharacterBuffer(int capacity) {
+                       fContent = new char[capacity];
+               }
+
+               /**
+                * Initialize with the given content.
+                * 
+                * @param string
+                *            the initial content
+                */
+               public CharacterBuffer(String content) {
+                       fContent = content.toCharArray();
+                       fLength = content.length();
+               }
+
+               /**
+                * Empties this buffer.
+                */
+               public void clear() {
+                       fIsHashCached = false;
+                       fLength = 0;
+               }
+
+               /**
+                * Appends the given character to the buffer.
+                * 
+                * @param c
+                *            the character
+                */
+               public void append(char c) {
+                       fIsHashCached = false;
+                       if (fLength == fContent.length) {
+                               char[] old = fContent;
+                               fContent = new char[old.length << 1];
+                               System.arraycopy(old, 0, fContent, 0, old.length);
+                       }
+                       fContent[fLength++] = c;
+               }
+
+               /**
+                * Returns the length of the content.
+                * 
+                * @return the length
+                */
+               public int length() {
+                       return fLength;
+               }
+
+               /**
+                * Returns the content as string.
+                * 
+                * @return the content
+                */
+               public String toString() {
+                       return new String(fContent, 0, fLength);
+               }
+
+               /**
+                * Returns the character at the given position.
+                * 
+                * @param i
+                *            the position
+                * @return the character at position <code>i</code>
+                */
+               public char charAt(int i) {
+                       return fContent[i];
+               }
+
+               /*
+                * @see java.lang.Object#hashCode()
+                */
+               public int hashCode() {
+                       if (fIsHashCached)
+                               return fHashCode;
+
+                       int hash = 0;
+                       for (int i = 0, n = fLength; i < n; i++)
+                               hash = 29 * hash + fContent[i];
+                       fHashCode = hash;
+                       fIsHashCached = true;
+                       return hash;
+               }
+
+               /*
+                * @see java.lang.Object#equals(java.lang.Object)
+                */
+               public boolean equals(Object obj) {
+                       if (obj == this)
+                               return true;
+                       if (!(obj instanceof CharacterBuffer))
+                               return false;
+                       CharacterBuffer buffer = (CharacterBuffer) obj;
+                       int length = buffer.length();
+                       if (length != fLength)
+                               return false;
+                       for (int i = 0; i < length; i++)
+                               if (buffer.charAt(i) != fContent[i])
+                                       return false;
+                       return true;
+               }
+
+               /**
+                * Is the content equal to the given string?
+                * 
+                * @param string
+                *            the string
+                * @return <code>true</code> iff the content is the same character
+                *         sequence as in the string
+                */
+               public boolean equals(String string) {
+                       int length = string.length();
+                       if (length != fLength)
+                               return false;
+                       for (int i = 0; i < length; i++)
+                               if (string.charAt(i) != fContent[i])
+                                       return false;
+                       return true;
+               }
+       }
+
+       /** Internal setting for the uninitialized column constraint */
+       private static final int UNDEFINED = -1;
+
+       /** The word detector used by this rule */
+       private IWordDetector fDetector;
+
+       /**
+        * The default token to be returned on success and if nothing else has been
+        * specified.
+        */
+       private IToken fDefaultToken;
+
+       /** The column constraint */
+       private int fColumn = UNDEFINED;
+
+       /** Buffer used for pattern detection */
+       private CharacterBuffer fBuffer = new CharacterBuffer(16);
+
+       /** List of word matchers */
+       private List fMatchers = new ArrayList();
+
+       /**
+        * Creates a rule which, with the help of an word detector, will return the
+        * token associated with the detected word. If no token has been associated,
+        * the scanner will be rolled back and an undefined token will be returned
+        * in order to allow any subsequent rules to analyze the characters.
+        * 
+        * @param detector
+        *            the word detector to be used by this rule, may not be
+        *            <code>null</code>
+        * 
+        * @see #addWord(String, IToken)
+        */
+       public CombinedWordRule(IWordDetector detector) {
+               this(detector, null, Token.UNDEFINED);
+       }
+
+       /**
+        * Creates a rule which, with the help of an word detector, will return the
+        * token associated with the detected word. If no token has been associated,
+        * the specified default token will be returned.
+        * 
+        * @param detector
+        *            the word detector to be used by this rule, may not be
+        *            <code>null</code>
+        * @param defaultToken
+        *            the default token to be returned on success if nothing else is
+        *            specified, may not be <code>null</code>
+        * 
+        * @see #addWord(String, IToken)
+        */
+       public CombinedWordRule(IWordDetector detector, IToken defaultToken) {
+               this(detector, null, defaultToken);
+       }
+
+       /**
+        * Creates a rule which, with the help of an word detector, will return the
+        * token associated with the detected word. If no token has been associated,
+        * the scanner will be rolled back and an undefined token will be returned
+        * in order to allow any subsequent rules to analyze the characters.
+        * 
+        * @param detector
+        *            the word detector to be used by this rule, may not be
+        *            <code>null</code>
+        * @param matcher
+        *            the initial word matcher
+        * 
+        * @see #addWord(String, IToken)
+        */
+       public CombinedWordRule(IWordDetector detector, WordMatcher matcher) {
+               this(detector, matcher, Token.UNDEFINED);
+       }
+
+       /**
+        * Creates a rule which, with the help of an word detector, will return the
+        * token associated with the detected word. If no token has been associated,
+        * the specified default token will be returned.
+        * 
+        * @param detector
+        *            the word detector to be used by this rule, may not be
+        *            <code>null</code>
+        * @param matcher
+        *            the initial word matcher
+        * @param defaultToken
+        *            the default token to be returned on success if nothing else is
+        *            specified, may not be <code>null</code>
+        * 
+        * @see #addWord(String, IToken)
+        */
+       public CombinedWordRule(IWordDetector detector, WordMatcher matcher,
+                       IToken defaultToken) {
+
+               Assert.isNotNull(detector);
+               Assert.isNotNull(defaultToken);
+
+               fDetector = detector;
+               fDefaultToken = defaultToken;
+               if (matcher != null)
+                       addWordMatcher(matcher);
+       }
+
+       /**
+        * Adds the given matcher.
+        * 
+        * @param matcher
+        *            the matcher
+        */
+       public void addWordMatcher(WordMatcher matcher) {
+               fMatchers.add(matcher);
+       }
+
+       /**
+        * Sets a column constraint for this rule. If set, the rule's token will
+        * only be returned if the pattern is detected starting at the specified
+        * column. If the column is smaller then 0, the column constraint is
+        * considered removed.
+        * 
+        * @param column
+        *            the column in which the pattern starts
+        */
+       public void setColumnConstraint(int column) {
+               if (column < 0)
+                       column = UNDEFINED;
+               fColumn = column;
+       }
+
+       /*
+        * @see IRule#evaluate(ICharacterScanner)
+        */
+       public IToken evaluate(ICharacterScanner scanner) {
+               int c = scanner.read();
+               if (fDetector.isWordStart((char) c)) {
+                       if (fColumn == UNDEFINED || (fColumn == scanner.getColumn() - 1)) {
+
+                               fBuffer.clear();
+                               do {
+                                       fBuffer.append((char) c);
+                                       c = scanner.read();
+                               } while (c != ICharacterScanner.EOF
+                                               && fDetector.isWordPart((char) c));
+                               scanner.unread();
+
+                               for (int i = 0, n = fMatchers.size(); i < n; i++) {
+                                       IToken token = ((WordMatcher) fMatchers.get(i)).evaluate(
+                                                       scanner, fBuffer);
+                                       if (!token.isUndefined())
+                                               return token;
+                               }
+
+                               if (fDefaultToken.isUndefined())
+                                       unreadBuffer(scanner);
+
+                               return fDefaultToken;
+                       }
+               }
+
+               scanner.unread();
+               return Token.UNDEFINED;
+       }
+
+       /**
+        * Returns the characters in the buffer to the scanner.
+        * 
+        * @param scanner
+        *            the scanner to be used
+        */
+       private void unreadBuffer(ICharacterScanner scanner) {
+               for (int i = fBuffer.length() - 1; i >= 0; i--)
+                       scanner.unread();
+       }
+}