SpanDocument.java

package edu.cmu.minorthird.text.gui;

import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.DefaultStyledDocument;
import javax.swing.text.SimpleAttributeSet;

/** A StyledDocument that holds a single span.
 *
 * @author William Cohen
 */

public class SpanDocument extends DefaultStyledDocument{

//    private edu.cmu.minorthird.text.Span span;
	
	static final long serialVersionUID=200803014L;
	
	private edu.cmu.minorthird.text.Span contextSpan;

	private int beginContextSpanInDocument,leftContextChars,rightContextChars;

	private edu.cmu.minorthird.text.Span leftBoundary,rightBoundary;

//    private int contextWidth = 0;

	public SpanDocument(){
		;
	}

	public SpanDocument(edu.cmu.minorthird.text.Span span){
		this(span,5);
	}

	public SpanDocument(edu.cmu.minorthird.text.Span span,int contextWidth){

//        this.span = span;
//        this.contextWidth = contextWidth;
//    log.debug(span.asString());
		int conLo=Math.max(span.documentSpanStartIndex()-contextWidth,0);
		int conHi=
				Math.min(span.documentSpanStartIndex()+span.size()+contextWidth,span
						.documentSpan().size());
		contextSpan=span.documentSpan().subSpan(conLo,conHi-conLo);

		beginContextSpanInDocument=contextSpan.getTextToken(0).getLo();
		leftContextChars=span.getTextToken(0).getLo()-beginContextSpanInDocument;
		rightContextChars=
				contextSpan.getTextToken(contextSpan.size()-1).getHi()-
						span.getTextToken(span.size()-1).getHi();

		leftBoundary=contextSpan.getLeftBoundary();
		rightBoundary=contextSpan.getRightBoundary();

		try{
			super.insertString(0,contextSpan.asString(),SimpleAttributeSet.EMPTY);
			resetHighlights();
		}catch(BadLocationException e){
			throw new IllegalStateException("inserting: "+e);
		}
	}

	/** Overrides default insertString, since insertions are not allowed. */
	@Override
	public void insertString(int off,String s,AttributeSet attribs)
			throws BadLocationException{
		; // do nothing
	}

	/** Overrides default insertString, since insertions are not allowed. */
	@Override
	public void remove(int off,int len) throws BadLocationException{
		; // do nothing
	}

	/** Clear all highlights. */
	public void resetHighlights(){
		setCharacterAttributes(0,getLength(),SimpleAttributeSet.EMPTY,true);
		setCharacterAttributes(0,leftContextChars,HiliteColors.gray,true);
		setCharacterAttributes(getLength()-rightContextChars,rightContextChars,
				HiliteColors.gray,true);
	}

	/** 
	 * Convert a character index in the text being displayed to a char index in the
	 * actual document which the display is a part of
	 */
	public int toLogicalCharIndex(int charIndex){
		return charIndex+beginContextSpanInDocument;
	}

	/** Highlight a subspan of the current span. */
	public void highlight(edu.cmu.minorthird.text.Span subspan,	AttributeSet attributeSet){
		if(
				subspan.getDocumentId().equals(contextSpan.getDocumentId())&&
				subspan.size()!=0&&
				subspan.getLeftBoundary().compareTo(leftBoundary)>=0&&
				subspan.getRightBoundary().compareTo(rightBoundary)<=0
				){
			int beginSubspanInDocument=subspan.getTextToken(0).getLo();
			int subspanLength=subspan.getTextToken(subspan.size()-1).getHi()-beginSubspanInDocument;
			setCharacterAttributes(beginSubspanInDocument-beginContextSpanInDocument,subspanLength,attributeSet,true);
		}
	}
}