Application: gvSIG desktop » gvSIG scripting

package org.gvsig.scripting.swing.impl.syntaxhighlight.styles;

import java.awt.Color;

import java.util.HashSet;

import java.util.Set;

import javax.swing.text.AttributeSet;

import javax.swing.text.BadLocationException;

import javax.swing.text.DefaultEditorKit;

import javax.swing.text.DefaultStyledDocument;

import javax.swing.text.Element;

import javax.swing.text.MutableAttributeSet;

import javax.swing.text.SimpleAttributeSet;

import javax.swing.text.StyleConstants;

public class JavaStyledDocument extends DefaultStyledDocument {

        /**

         * 

         */

        private static final long serialVersionUID = 2859530660266127826L;

        private final DefaultStyledDocument doc;

        private final Element rootElement;

        private boolean multiLineComment;

        private final MutableAttributeSet normal;

        private final MutableAttributeSet keyword;

        private final MutableAttributeSet comment;

        private final MutableAttributeSet quote;

    private final Set<String> keywords;

        public JavaStyledDocument()

        {

                doc = this;

                rootElement = doc.getDefaultRootElement();

                putProperty( DefaultEditorKit.EndOfLineStringProperty, "\n" );

                normal = new SimpleAttributeSet();

                StyleConstants.setForeground(normal, Color.black);

                comment = new SimpleAttributeSet();

                StyleConstants.setForeground(comment, Color.gray);

                StyleConstants.setItalic(comment, true);

                keyword = new SimpleAttributeSet();

                StyleConstants.setForeground(keyword, Color.blue);

                quote = new SimpleAttributeSet();

                StyleConstants.setForeground(quote, Color.red);

        keywords = new HashSet<String>();

                keywords.add( "abstract" );

                keywords.add( "boolean" );

                keywords.add( "break" );

                keywords.add( "byte" );

                keywords.add( "byvalue" );

                keywords.add( "case" );

                keywords.add( "cast" );

                keywords.add( "catch" );

                keywords.add( "char" );

                keywords.add( "class" );

                keywords.add( "const" );

                keywords.add( "continue" );

                keywords.add( "default" );

                keywords.add( "do" );

                keywords.add( "double" );

                keywords.add( "else" );

                keywords.add( "extends" );

                keywords.add( "false" );

                keywords.add( "final" );

                keywords.add( "finally" );

                keywords.add( "float" );

                keywords.add( "for" );

                keywords.add( "future" );

                keywords.add( "generic" );

                keywords.add( "goto" );

                keywords.add( "if" );

                keywords.add( "implements" );

                keywords.add( "import" );

                keywords.add( "inner" );

                keywords.add( "instanceof" );

                keywords.add( "int" );

                keywords.add( "interface" );

                keywords.add( "long" );

                keywords.add( "native" );

                keywords.add( "new" );

                keywords.add( "null" );

                keywords.add( "operator" );

                keywords.add( "outer" );

                keywords.add( "package" );

                keywords.add( "private" );

                keywords.add( "protected" );

                keywords.add( "public" );

                keywords.add( "rest" );

                keywords.add( "return" );

                keywords.add( "short" );

                keywords.add( "static" );

                keywords.add( "super" );

                keywords.add( "switch" );

                keywords.add( "synchronized" );

                keywords.add( "this" );

                keywords.add( "throw" );

                keywords.add( "throws" );

                keywords.add( "transient" );

                keywords.add( "true" );

                keywords.add( "try" );

                keywords.add( "var" );

                keywords.add( "void" );

                keywords.add( "volatile" );

                keywords.add( "while" );

        }

        /*

         *  Override to apply syntax highlighting after the document has been updated

         */

        @Override

    public void insertString(int offset, String str, AttributeSet a) throws BadLocationException

        {

                if (str.equals("{"))

                        str = addMatchingBrace(offset);

                super.insertString(offset, str, a);

                processChangedLines(offset, str.length());

        }

        /*

         *  Override to apply syntax highlighting after the document has been updated

         */

        @Override

    public void remove(int offset, int length) throws BadLocationException

        {

                super.remove(offset, length);

                processChangedLines(offset, 0);

        }

        /*

         *  Determine how many lines have been changed,

         *  then apply highlighting to each line

         */

        public void processChangedLines(int offset, int length)

                throws BadLocationException

        {

                String content = doc.getText(0, doc.getLength());

                //  The lines affected by the latest document update

                int startLine = rootElement.getElementIndex( offset );

                int endLine = rootElement.getElementIndex( offset + length );

                //  Make sure all comment lines prior to the start line are commented

                //  and determine if the start line is still in a multi line comment

                setMultiLineComment( commentLinesBefore( content, startLine ) );

                //  Do the actual highlighting

                for (int i = startLine; i <= endLine; i++)

                {

                        applyHighlighting(content, i);

                }

                //  Resolve highlighting to the next end multi line delimiter

                if (isMultiLineComment())

                        commentLinesAfter(content, endLine);

                else

                        highlightLinesAfter(content, endLine);

        }

        /*

         *  Highlight lines when a multi line comment is still 'open'

         *  (ie. matching end delimiter has not yet been encountered)

         */

        private boolean commentLinesBefore(String content, int line)

        {

                int offset = rootElement.getElement( line ).getStartOffset();

                //  Start of comment not found, nothing to do

                int startDelimiter = lastIndexOf( content, getStartDelimiter(), offset - 2 );

                if (startDelimiter < 0)

                        return false;

                //  Matching start/end of comment found, nothing to do

                int endDelimiter = indexOf( content, getEndDelimiter(), startDelimiter );

                if (endDelimiter < offset & endDelimiter != -1)

                        return false;

                //  End of comment not found, highlight the lines

                doc.setCharacterAttributes(startDelimiter, offset - startDelimiter + 1, comment, false);

                return true;

        }

        /*

         *  Highlight comment lines to matching end delimiter

         */

        private void commentLinesAfter(String content, int line)

        {

                int offset = rootElement.getElement( line ).getEndOffset();

                //  End of comment not found, nothing to do

                int endDelimiter = indexOf( content, getEndDelimiter(), offset );

                if (endDelimiter < 0)

                        return;

                //  Matching start/end of comment found, comment the lines

                int startDelimiter = lastIndexOf( content, getStartDelimiter(), endDelimiter );

                if (startDelimiter < 0 || startDelimiter <= offset)

                {

                        doc.setCharacterAttributes(offset, endDelimiter - offset + 1, comment, false);

                }

        }

        /*

         *  Highlight lines to start or end delimiter

         */

        private void highlightLinesAfter(String content, int line)

                throws BadLocationException

        {

                int offset = rootElement.getElement( line ).getEndOffset();

                //  Start/End delimiter not found, nothing to do

                int startDelimiter = indexOf( content, getStartDelimiter(), offset );

                int endDelimiter = indexOf( content, getEndDelimiter(), offset );

                if (startDelimiter < 0)

                        startDelimiter = content.length();

                if (endDelimiter < 0)

                        endDelimiter = content.length();

                int delimiter = Math.min(startDelimiter, endDelimiter);

                if (delimiter < offset)

                        return;

                //        Start/End delimiter found, reapply highlighting

                int endLine = rootElement.getElementIndex( delimiter );

                for (int i = line + 1; i < endLine; i++)

                {

                        Element branch = rootElement.getElement( i );

                        Element leaf = doc.getCharacterElement( branch.getStartOffset() );

                        AttributeSet as = leaf.getAttributes();

                        if ( as.isEqual(comment) )

                                applyHighlighting(content, i);

                }

        }

        /*

         *  Parse the line to determine the appropriate highlighting

         */

        private void applyHighlighting(String content, int line)

                throws BadLocationException

        {

                int startOffset = rootElement.getElement( line ).getStartOffset();

                int endOffset = rootElement.getElement( line ).getEndOffset() - 1;

                int lineLength = endOffset - startOffset;

                int contentLength = content.length();

                if (endOffset >= contentLength)

                        endOffset = contentLength - 1;

                //  check for multi line comments

                //  (always set the comment attribute for the entire line)

                if (endingMultiLineComment(content, startOffset, endOffset)

                ||  isMultiLineComment()

                ||  startingMultiLineComment(content, startOffset, endOffset) )

                {

                        doc.setCharacterAttributes(startOffset, endOffset - startOffset + 1, comment, false);

                        return;

                }

                //  set normal attributes for the line

                doc.setCharacterAttributes(startOffset, lineLength, normal, true);

                //  check for single line comment

                int index = content.indexOf(getSingleLineDelimiter(), startOffset);

                if ( (index > -1) && (index < endOffset) )

                {

                        doc.setCharacterAttributes(index, endOffset - index + 1, comment, false);

                        endOffset = index - 1;

                }

                //  check for tokens

                checkForTokens(content, startOffset, endOffset);

        }

        /*

         *  Does this line contain the start delimiter

         */

        private boolean startingMultiLineComment(String content, int startOffset, int endOffset)

                throws BadLocationException

        {

                int index = indexOf( content, getStartDelimiter(), startOffset );

                if ( (index < 0) || (index > endOffset) )

                        return false;

                else

                {

                        setMultiLineComment( true );

                        return true;

                }

        }

        /*

         *  Does this line contain the end delimiter

         */

        private boolean endingMultiLineComment(String content, int startOffset, int endOffset)

                throws BadLocationException

        {

                int index = indexOf( content, getEndDelimiter(), startOffset );

                if ( (index < 0) || (index > endOffset) )

                        return false;

                else

                {

                        setMultiLineComment( false );

                        return true;

                }

        }

        /*

         *  We have found a start delimiter

         *  and are still searching for the end delimiter

         */

        private boolean isMultiLineComment()

        {

                return multiLineComment;

        }

        private void setMultiLineComment(boolean value)

        {

                multiLineComment = value;

        }

        /*

         *        Parse the line for tokens to highlight

         */

        private void checkForTokens(String content, int startOffset, int endOffset)

        {

                while (startOffset <= endOffset)

                {

                        //  skip the delimiters to find the start of a new token

                        while ( isDelimiter( content.substring(startOffset, startOffset + 1) ) )

                        {

                                if (startOffset < endOffset)

                                        startOffset++;

                                else

                                        return;

                        }

                        //  Extract and process the entire token

                        if ( isQuoteDelimiter( content.substring(startOffset, startOffset + 1) ) )

                                startOffset = getQuoteToken(content, startOffset, endOffset);

                        else

                                startOffset = getOtherToken(content, startOffset, endOffset);

                }

        }

        /*

         *

         */

        private int getQuoteToken(String content, int startOffset, int endOffset)

        {

                String quoteDelimiter = content.substring(startOffset, startOffset + 1);

                String escapeString = getEscapeString(quoteDelimiter);

                int index;

                int endOfQuote = startOffset;

                //  skip over the escape quotes in this quote

                index = content.indexOf(escapeString, endOfQuote + 1);

                while ( (index > -1) && (index < endOffset) )

                {

                        endOfQuote = index + 1;

                        index = content.indexOf(escapeString, endOfQuote);

                }

                // now find the matching delimiter

                index = content.indexOf(quoteDelimiter, endOfQuote + 1);

                if ( (index < 0) || (index > endOffset) )

                        endOfQuote = endOffset;

                else

                        endOfQuote = index;

                doc.setCharacterAttributes(startOffset, endOfQuote - startOffset + 1, quote, false);

                return endOfQuote + 1;

        }

        /*

         *

         */

        private int getOtherToken(String content, int startOffset, int endOffset)

        {

                int endOfToken = startOffset + 1;

                while ( endOfToken <= endOffset )

                {

                        if ( isDelimiter( content.substring(endOfToken, endOfToken + 1) ) )

                                break;

                        endOfToken++;

                }

                String token = content.substring(startOffset, endOfToken);

                if ( isKeyword( token ) )

                {

                        doc.setCharacterAttributes(startOffset, endOfToken - startOffset, keyword, false);

                }

                return endOfToken + 1;

        }

        /*

         *  Assume the needle will the found at the start/end of the line

         */

        private int indexOf(String content, String needle, int offset)

        {

                int index;

                while ( (index = content.indexOf(needle, offset)) != -1 )

                {

                        String text = getLine( content, index ).trim();

                        if (text.startsWith(needle) || text.endsWith(needle))

                                break;

                        else

                                offset = index + 1;

                }

                return index;

        }

        /*

         *  Assume the needle will the found at the start/end of the line

         */

        private int lastIndexOf(String content, String needle, int offset)

        {

                int index;

                while ( (index = content.lastIndexOf(needle, offset)) != -1 )

                {

                        String text = getLine( content, index ).trim();

                        if (text.startsWith(needle) || text.endsWith(needle))

                                break;

                        else

                                offset = index - 1;

                }

                return index;

        }

        private String getLine(String content, int offset)

        {

                int line = rootElement.getElementIndex( offset );

                Element lineElement = rootElement.getElement( line );

                int start = lineElement.getStartOffset();

                int end = lineElement.getEndOffset();

                return content.substring(start, end - 1);

        }

        /*

         *  Override for other languages

         */

        protected boolean isDelimiter(String character)

        {

                String operands = ";:{}()[]+-/%<=>!&|^~*";

                if (Character.isWhitespace( character.charAt(0) ) ||

                        operands.indexOf(character) != -1 )

                        return true;

                else

                        return false;

        }

        /*

         *  Override for other languages

         */

        protected boolean isQuoteDelimiter(String character)

        {

                String quoteDelimiters = "\"'";

                if (quoteDelimiters.indexOf(character) < 0)

                        return false;

                else

                        return true;

        }

        /*

         *  Override for other languages

         */

        protected boolean isKeyword(String token)

        {

                return keywords.contains( token );

        }

        /*

         *  Override for other languages

         */

        protected String getStartDelimiter()

        {

                return "/*";

        }

        /*

         *  Override for other languages

         */

        protected String getEndDelimiter()

        {

                return "*/";

        }

        /*

         *  Override for other languages

         */

        protected String getSingleLineDelimiter()

        {

                return "//";

        }

        /*

         *  Override for other languages

         */

        protected String getEscapeString(String quoteDelimiter)

        {

                return "\\" + quoteDelimiter;

        }

        /*

         *

         */

        protected String addMatchingBrace(int offset) throws BadLocationException

        {

                StringBuffer whiteSpace = new StringBuffer();

                int line = rootElement.getElementIndex( offset );

                int i = rootElement.getElement(line).getStartOffset();

                while (true)

                {

                        String temp = doc.getText(i, 1);

                        if (temp.equals(" ") || temp.equals("\t"))

                        {

                                whiteSpace.append(temp);

                                i++;

                        }

                        else

                                break;

                }

                return "{\n" + whiteSpace.toString() + "\t\n" + whiteSpace.toString() + "}";

        }

}