columntext.java

java itext java itext java itext

/*
 * $Id: ColumnText.java,v 1.12 2001/12/10 13:53:21 blowagie Exp $
 * $Name:  $
 *
 * Copyright 2001 by Paulo Soares
 *
 * This library is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Library General Public License as published
 * by the Free Software Foundation; either version 2 of the License, or 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 Library general Public License for more
 * details.
 *
 * You should have received a copy of the GNU Library General Public License along
 * with this library; if not, write to the Free Foundation, Inc., 59 Temple Place,
 * Suite 330, Boston, MA 02111-1307 USA.
 *
 * If you didn't download this code from the following link, you should check if
 * you aren't using an obsolete version:
 * http://www.lowagie.com/iText/
 *
 * ir-arch Bruno Lowagie,
 * Adolf Baeyensstraat 121
 * 9040 Sint-Amandsberg
 * BELGIUM
 * tel. [phone]
 * [e-mail]
 *
 */

package com.lowagie.text.pdf;
import java.util.ArrayList;
import java.util.Iterator;
import com.lowagie.text.Phrase;
import com.lowagie.text.Chunk;
import com.lowagie.text.Element;
import com.lowagie.text.DocumentException;

/**
 * Formats text in a columnwise form. The text is bound
 * on the left and on the right by a sequence of lines. This allows the column
 * to have any shape, not only rectangular.
 * <P>
 * Several parameters can be set like the first paragraph line indent and
 * extra space between paragraphs.
 * <P>
 * A call to the method <CODE>go</CODE> will return one of the following
 * situations: the column ended or the text ended.
 * <P>
 * I the column ended, a new column definition can be loaded with the method
 * <CODE>setColumns</CODE> and the method <CODE>go</CODE> can be called again.
 * <P>
 * If the text ended, more text can be loaded with <CODE>addText</CODE>
 * and the method <CODE>go</CODE> can be called again.<BR>
 * The only limitation is that one or more complete paragraphs must be loaded
 * each time.
 * @author Paulo Soares ([e-mail])
 */
 
public class ColumnText {

/** Signals that there are no more text available. */    
    public static final int NO_MORE_TEXT = 1;
	
/** Signals that there is no more column. */    
    public static final int NO_MORE_COLUMN = 2;
    
/** The column is valid. */    
    protected static final int LINE_STATUS_OK = 0;
	
/** The line is out outhe column limits. */    
    protected static final int LINE_STATUS_OFFLIMITS = 1;
	
/** The line cannot fit this column position. */    
    protected static final int LINE_STATUS_NOLINE = 2;
    
/** Upper bound of the column. */    
    protected float maxY;
	
/** Lower bound of the column. */    
    protected float minY;
	
/** The column alignment. Default is left alignment. */    
    protected int alignment = Element.ALIGN_LEFT;
	
/** The left column bound. */    
    protected ArrayList leftWall;
	
/** The right column bound. */    
    protected ArrayList rightWall;
	
/** The chunks that form the text. */    
    protected ArrayList chunks = new ArrayList();
	
/** The current y line location. Text will be written at this line minus the leading. */    
    protected float yLine;
	
/** The leading for the current line. */    
    protected float currentLeading = 16;
	
/** The fixed text leading. */    
    protected float fixedLeading = 16;
	
/** The text leading that is multiplied by the biggest font size in the line. */    
    protected float multipliedLeading = 0;
	
/** The <CODE>PdfContent</CODE> where the text will be written to. */    
    protected PdfContentByte text;
	
/** The line status when trying to fit a line to a column. */    
    protected int lineStatus;
	
/** The first paragraph line indent. */    
    protected float indent = 0;
	
/** The extra space between paragraphs. */    
    protected float extraParagraphSpace = 0;
	
/** Marks the chunks to be eliminated when the line is written. */    
    protected int currentChunkMarker = -1;
	
/** The chunk created by the splitting. */    
    protected PdfChunk currentStandbyChunk;
	
/** The chunk created by the splitting. */    
    protected String splittedChunkText;
    
/** The width of the line when the column is defined as a simple rectangle. */    
    protected float rectangularWidth = -1;
    
/**
 * Creates a <CODE>ColumnText</CODE>.
 * @param text the place where the text will be written to. Can
 * be a template.
 */    
    public ColumnText(PdfContentByte text)
    {
        this.text = text;
    }
    
/**
 * Adds a <CODE>Phrase</CODE> to the current text array.
 * @param phrase the text
 */    
    public void addText(Phrase phrase)
    {
        for (Iterator j = phrase.getChunks().iterator(); j.hasNext();)
        {
            chunks.add(new PdfChunk((Chunk)j.next(), null));
        }
    }
    
/**
 * Adds a <CODE>Chunk</CODE> to the current text array.
 * @param chunk the text
 */    
    public void addText(Chunk chunk)
    {
        chunks.add(new PdfChunk(chunk, null));
    }
    
/**
 * Converts a sequence of lines representing one of the column bounds into
 * an internal format.
 * <p>
 * Each array element will contain a <CODE>float[4]</CODE> representing
 * the line x = ax + b.
 * @param cLine the column array
 * @return the converted array
 */    
    protected ArrayList convertColumn(float cLine[])
    {
        if (cLine.length < 4)
            throw new RuntimeException("No valid column line found.");
        ArrayList cc = new ArrayList();
        for (int k = 0; k < cLine.length - 2; k += 2) {
            float x1 = cLine[k];
            float y1 = cLine[k + 1];
            float x2 = cLine[k + 2];
            float y2 = cLine[k + 3];
            if (y1 == y2)
                continue;
            // x = ay + b
            float a = (x1 - x2) / (y1 - y2);
            float b = x1 - a * y1;
            float r[] = new float[4];
            r[0] = Math.min(y1, y2);
            r[1] = Math.max(y1, y2);
            r[2] = a;
            r[3] = b;
            cc.add(r);
            maxY = Math.max(maxY, r[1]);
            minY = Math.min(minY, r[0]);
        }
        if (cc.size() == 0)
            throw new RuntimeException("No valid column line found.");
        return cc;
    }
    
/**
 * Finds the intersection between the <CODE>yLine</CODE> and the column. It will
 * set the <CODE>lineStatus</CODE> apropriatly.
 * @param wall the column to intersect
 * @return the x coordinate of the intersection
 */    
    protected float findLimitsPoint(ArrayList wall)
    {
        lineStatus = LINE_STATUS_OK;
        if (yLine < minY || yLine > maxY) {
            lineStatus = LINE_STATUS_OFFLIMITS;
            return 0;
        }
        for (int k = 0; k < wall.size(); ++k) {
            float r[] = (float[])wall.get(k);
            if (yLine < r[0] || yLine > r[1])
                continue;
            return r[2] * yLine + r[3];
        }
        lineStatus = LINE_STATUS_NOLINE;
        return 0;
    }
    
/**
 * Finds the intersection between the <CODE>yLine</CODE> and the two
 * column bounds. It will set the <CODE>lineStatus</CODE> apropriatly.
 * @return a <CODE>float[2]</CODE>with the x coordinates of the intersection
 */    
    protected float[] findLimitsOneLine()
    {
        for (;;) {
            float x1 = findLimitsPoint(leftWall);
            if (lineStatus == LINE_STATUS_OFFLIMITS || lineStatus == LINE_STATUS_NOLINE)
                return null;
            float x2 = findLimitsPoint(rightWall);
            if (lineStatus == LINE_STATUS_NOLINE)
                return null;
            return new float[]{x1, x2};
        }
    }
    
/**
 * Finds the intersection between the <CODE>yLine</CODE>,
 * the <CODE>yLine-leading</CODE>and the two
 * column bounds. It will set the <CODE>lineStatus</CODE> apropriatly.
 * @return a <CODE>float[4]</CODE>with the x coordinates of the intersection
 */    
    protected float[] findLimitsTwoLines()
    {
        for (;;) {
            float x1[] = findLimitsOneLine();
            if (lineStatus == LINE_STATUS_OFFLIMITS)
                return null;
            yLine -= currentLeading;
            if (lineStatus == LINE_STATUS_NOLINE) {
                continue;
            }
            float x2[] = findLimitsOneLine();
            if (lineStatus == LINE_STATUS_OFFLIMITS)
                return null;
            if (lineStatus == LINE_STATUS_NOLINE) {
                yLine -= currentLeading;
                continue;
            }
            if (x1[0] >= x2[1] || x2[0] >= x1[1])
                continue;
            return new float[]{x1[0], x1[1], x2[0], x2[1]};
        }
    }
    
/**
 * Sets the columns bounds. Each column bound is described by a
 * <CODE>float[]</CODE> with the line points [x1,y1,x2,y2,...].
 * The array must have at least 4 elements.
 * @param leftLine the left column bound
 * @param rightLine the right column bound
 */    
    public void setColumns(float leftLine[], float rightLine[])
    {
        rightWall = convertColumn(rightLine);
        leftWall = convertColumn(leftLine);
        rectangularWidth = -1;
    }
    
/**
 * Simplified method for rectangular columns.
 * @param phrase a <CODE>Phrase</CODE>
 * @param llx the lower left x corner
 * @param lly the lower left y corner
 * @param urx the upper right x corner
 * @param ury the upper right y corner
 * @param leading the leading
 * @param alignment the column alignment
 */    
    public void setSimpleColumn(Phrase phrase, float llx, float lly, float urx, float ury, float leading, int alignment)
    {
        addText(phrase);
        setSimpleColumn(llx, lly, urx, ury, leading, alignment);
    }
    
/**
 * Simplified method for rectangular columns.
 * @param llx the lower left x corner
 * @param lly the lower left y corner
 * @param urx the upper right x corner