/*
* 10/28/2004
*
* DefaultTokenFactory.java - Default token factory.
* Copyright (C) 2004 Robert Futrell
* robert_futrell at users.sourceforge.net
* http://fifesoft.com/rsyntaxtextarea
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
*/
package org.fife.ui.rsyntaxtextarea;
import javax.swing.text.Segment;
/**
* This class generates tokens for a {@link TokenMaker}. This class is here because it reuses tokens when they aren't
* needed anymore to prevent This class doesn't actually create new tokens every time <code>createToken</code> is
* called. Instead, it internally keeps a stack of available already-created tokens. When more tokens are needed to
* properly display a line, more tokens are added to the available stack. This saves from needless repetitive memory
* allocation. However, it makes it IMPERATIVE that users call <code>resetTokenList</code> when creating a new token
* list so that the token maker can keep an accurate list of available tokens.
* <p>
*
* NOTE: This class should only be used by {@link TokenMaker}; nobody else needs it!
*
* @author Robert Futrell
* @version 0.1
*/
class DefaultTokenFactory implements TokenFactory {
private int size;
private int increment;
private Token[] tokenList;
private int currentFreeToken;
protected static final int DEFAULT_START_SIZE = 30;
protected static final int DEFAULT_INCREMENT = 10;
/**
* Cosnstructor.
*/
public DefaultTokenFactory() {
this(DEFAULT_START_SIZE, DEFAULT_INCREMENT);
}
/**
* Constructor.
*
* @param size
* The initial number of tokens in this factory.
* @param increment
* How many tokens to increment by when the stack gets empty.
*/
public DefaultTokenFactory(int size, int increment) {
this.size = size;
this.increment = increment;
this.currentFreeToken = 0;
// Give us some tokens to initially work with.
tokenList = new Token[size];
for (int i = 0; i < size; i++)
tokenList[i] = createInternalUseOnlyToken();
}
/**
* Adds tokens to the internal token list. This is called whenever a request is made and no more tokens are
* available.
*/
private final void augmentTokenList() {
Token[] temp = new Token[size + increment];
System.arraycopy(tokenList, 0, temp, 0, size);
size += increment;
tokenList = temp;
for (int i = 0; i < increment; i++) {
tokenList[size - i - 1] = createInternalUseOnlyToken();
}
// System.err.println("... size up to: " + size);
}
/**
* Creates a token for use internally by this token factory. This method should NOT be called externally; only by
* this class and possibly subclasses.
*
* @return A token to add to this token factory's internal stack. If a subclass wants to produce a stack of a token
* other than {@link DefaultToken}, then this method can be overridden to return a new instance of the
* desired token type.
*/
protected Token createInternalUseOnlyToken() {
return new DefaultToken();
}
/**
* Returns a null token.
*
* @return A null token.
*/
public Token createToken() {
Token token = tokenList[currentFreeToken];
token.text = null;
token.type = Token.NULL;
token.offset = -1;
token.setNextToken(null);
currentFreeToken++;
if (currentFreeToken == size)
augmentTokenList();
return token;
}
/**
* Returns a token.
*
* @param line
* The segment from which to get the token's text.
* @param beg
* The starting offset of the token's text in the segment.
* @param end
* The ending offset of the token's text in the segment.
* @param startOffset
* The offset in the document of the token.
* @param type
* The type of token.
* @return The token.
*/
public Token createToken(final Segment line, final int beg,
final int end, final int startOffset, final int type) {
return createToken(line.array, beg, end, startOffset, type);
}
/**
* Returns a token.
*
* @param line
* The segment from which to get the token's text.
* @param beg
* The starting offset of the token's text in the segment.
* @param end
* The ending offset of the token's text in the segment.
* @param startOffset
* The offset in the document of the token.
* @param type
* The type of token.
* @return The token.
*/
public Token createToken(final char[] line, final int beg,
final int end, final int startOffset, final int type) {
Token token = tokenList[currentFreeToken];
token.set(line, beg, end, startOffset, type);
currentFreeToken++;
if (currentFreeToken == size)
augmentTokenList();
return token;
}
/**
* Resets the state of this token maker. This method should be called by the <code>TokenMaker</code> every time a
* token list is generated for a new line so the tokens can be reused.
*/
public void resetAllTokens() {
currentFreeToken = 0;
}
}