/*
* 08/26/2004
*
* TokenMakerBase.java - A base class for token makers.
*
* This library is distributed under a modified BSD license. See the included
* RSyntaxTextArea.License.txt file for details.
*/
package org.fife.ui.rsyntaxtextarea;
import javax.swing.Action;
import javax.swing.text.Segment;
/**
* Base class for token makers.
*
* @author Robert Futrell
* @version 1.0
*/
public abstract class TokenMakerBase implements TokenMaker {
/**
* The first token in the returned linked list.
*/
protected TokenImpl firstToken;
/**
* Used in the creation of the linked list.
*/
protected TokenImpl currentToken;
/**
* Used in the creation of the linked list.
*/
protected TokenImpl previousToken;
/**
* The factory that gives us our tokens to use.
*/
private TokenFactory tokenFactory;
/**
* Highlights occurrences of the current token in the editor, if it is
* relevant.
*/
private OccurrenceMarker occurrenceMarker;
/**
* "0" implies this is the "main" language being highlighted. Positive
* values imply various "secondary" or "embedded" languages, such as CSS
* or JavaScript in HTML. While this value is non-zero, tokens will be
* generated with this language index so they can (possibly) be painted
* differently, so "embedded" languages can be rendered with a special
* background.
*/
private int languageIndex;
/**
* Constructor.
*/
public TokenMakerBase() {
firstToken = currentToken = previousToken = null;
tokenFactory = new DefaultTokenFactory();
}
/**
* {@inheritDoc}
*/
public void addNullToken() {
if (firstToken==null) {
firstToken = tokenFactory.createToken();
currentToken = firstToken;
}
else {
TokenImpl next = tokenFactory.createToken();
currentToken.setNextToken(next);
previousToken = currentToken;
currentToken = next;
}
currentToken.setLanguageIndex(languageIndex);
}
/**
* Adds the token specified to the current linked list of tokens.
*
* @param segment <code>Segment</code> to get text from.
* @param start Start offset in <code>segment</code> of token.
* @param end End offset in <code>segment</code> of token.
* @param tokenType The token's type.
* @param startOffset The offset in the document at which this token
* occurs.
*/
public void addToken(Segment segment, int start, int end, int tokenType,
int startOffset) {
addToken(segment.array, start,end, tokenType, startOffset);
}
/**
* {@inheritDoc}
*/
public void addToken(char[] array, int start, int end, int tokenType,
int startOffset) {
addToken(array, start, end, tokenType, startOffset, false);
}
/**
* Adds the token specified to the current linked list of tokens.
*
* @param array The character array.
* @param start The starting offset in the array.
* @param end The ending offset in the array.
* @param tokenType The token's type.
* @param startOffset The offset in the document at which this token
* occurs.
* @param hyperlink Whether this token is a hyperlink.
*/
public void addToken(char[] array, int start, int end, int tokenType,
int startOffset, boolean hyperlink) {
if (firstToken==null) {
firstToken = tokenFactory.createToken(array, start, end,
startOffset, tokenType);
currentToken = firstToken; // previous token is still null.
}
else {
TokenImpl next = tokenFactory.createToken(array, start,end,
startOffset, tokenType);
currentToken.setNextToken(next);
previousToken = currentToken;
currentToken = next;
}
currentToken.setLanguageIndex(languageIndex);
currentToken.setHyperlink(hyperlink);
}
/**
* Returns the occurrence marker to use for this token maker. Subclasses
* can override to use different implementations.
*
* @return The occurrence marker to use.
*/
protected OccurrenceMarker createOccurrenceMarker() {
return new DefaultOccurrenceMarker();
}
/**
* Returns the closest {@link TokenTypes "standard" token type} for a given
* "internal" token type (e.g. one whose value is <code>< 0</code>).<p>
*
* The default implementation returns <code>type</code> always, which
* denotes that a mapping from internal token types to standard token types
* is not defined; subclasses can override.
*
* @param type The token type.
* @return The closest "standard" token type.
*/
public int getClosestStandardTokenTypeForInternalType(int type) {
return type;
}
/**
* Returns whether this programming language uses curly braces
* ('<code>{</code>' and '<code>}</code>') to denote code blocks.
*
* The default implementation returns <code>false</code>; subclasses can
* override this method if necessary.
*
* @param languageIndex The language index at the offset in question.
* Since some <code>TokenMaker</code>s effectively have nested
* languages (such as JavaScript in HTML), this parameter tells the
* <code>TokenMaker</code> what sub-language to look at.
* @return Whether curly braces denote code blocks.
*/
public boolean getCurlyBracesDenoteCodeBlocks(int languageIndex) {
return false;
}
/**
* Returns an action to handle "insert break" key presses (i.e. Enter).
* The default implementation returns <code>null</code>. Subclasses
* can override.
*
* @return The default implementation always returns <code>null</code>.
*/
public Action getInsertBreakAction() {
return null;
}
/**
* Returns the current language index.
*
* @return The current language index.
* @see #setLanguageIndex(int)
*/
protected int getLanguageIndex() {
return languageIndex;
}
/**
* {@inheritDoc}
*/
public int getLastTokenTypeOnLine(Segment text, int initialTokenType) {
// Last parameter doesn't matter if we're not painting.
Token t = getTokenList(text, initialTokenType, 0);
while (t.getNextToken()!=null)
t = t.getNextToken();
return t.getType();
}
/**
* {@inheritDoc}
*/
public String[] getLineCommentStartAndEnd(int languageIndex) {
return null;
}
/**
* Returns whether tokens of the specified type should have "mark
* occurrences" enabled for the current programming language. The default
* implementation returns true if <tt>type</tt> is {@link Token#IDENTIFIER}.
* Subclasses can override this method to support other token types, such
* as {@link Token#VARIABLE}.
*
* @param type The token type.
* @return Whether tokens of this type should have "mark occurrences"
* enabled.
*/
public boolean getMarkOccurrencesOfTokenType(int type) {
return type==Token.IDENTIFIER;
}
/**
* {@inheritDoc}
*/
public OccurrenceMarker getOccurrenceMarker() {
if (occurrenceMarker==null) {
occurrenceMarker = createOccurrenceMarker();
}
return occurrenceMarker;
}
/**
* The default implementation returns <code>false</code> always. Languages
* that wish to better support auto-indentation can override this method.
*
* @param token The token the previous line ends with.
* @return Whether the next line should be indented.
*/
public boolean getShouldIndentNextLineAfter(Token token) {
return false;
}
/**
* Returns whether a character could be part of an "identifier" token
* in a specific language. The default implementation returns
* <code>true</code> for letters, numbers, and certain symbols.
*/
public boolean isIdentifierChar(int languageIndex, char ch) {
return Character.isLetterOrDigit(ch) || ch=='_' || ch=='$';
}
/**
* The default implementation returns <code>false</code> always.
* Subclasses that are highlighting a markup language should override this
* method to return <code>true</code>.
*
* @return <code>false</code> always.
*/
public boolean isMarkupLanguage() {
return false;
}
/**
* Deletes the linked list of tokens so we can begin anew. This should
* never have to be called by the programmer, as it is automatically
* called whenever the user calls
* {@link #getLastTokenTypeOnLine(Segment, int)} or
* {@link #getTokenList(Segment, int, int)}.
*/
protected void resetTokenList() {
firstToken = currentToken = previousToken = null;
tokenFactory.resetAllTokens();
}
/**
* Sets the language index to assign to tokens moving forward. This
* property is used to designate tokens as being in "secondary" languages
* (such as CSS or JavaScript in HTML).
*
* @param languageIndex The new language index. A value of
* <code>0</code> denotes the "main" language, any positive value
* denotes a specific secondary language. Negative values will
* be treated as <code>0</code>.
* @see #getLanguageIndex()
*/
protected void setLanguageIndex(int languageIndex) {
this.languageIndex = Math.max(0, languageIndex);
}
}