pdfont.java

非常有用的操作pdf文件的java源码

/**
 * Copyright (c) 2003-2006, www.pdfbox.org
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. Neither the name of pdfbox; nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * http://www.pdfbox.org
 *
 */
package org.pdfbox.pdmodel.font;

import org.fontbox.afm.AFMParser;

import org.fontbox.afm.FontMetric;

import org.fontbox.cmap.CMapParser;

import org.fontbox.cmap.CMap;

import org.pdfbox.encoding.AFMEncoding;
import org.pdfbox.encoding.DictionaryEncoding;
import org.pdfbox.encoding.Encoding;
import org.pdfbox.encoding.EncodingManager;

import org.pdfbox.cos.COSArray;
import org.pdfbox.cos.COSBase;
import org.pdfbox.cos.COSDictionary;
import org.pdfbox.cos.COSFloat;
import org.pdfbox.cos.COSName;
import org.pdfbox.cos.COSNumber;
import org.pdfbox.cos.COSStream;

import org.pdfbox.pdmodel.common.COSArrayList;
import org.pdfbox.pdmodel.common.COSObjectable;
import org.pdfbox.pdmodel.common.PDMatrix;
import org.pdfbox.pdmodel.common.PDRectangle;

import org.pdfbox.util.ResourceLoader;

import java.awt.Graphics;

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.IOException;

import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.StringTokenizer;

/**
 * This is the base class for all PDF fonts.
 *
 * @author <a href="mailto:[e-mail]">Ben Litchfield</a>
 * @version $Revision: 1.43 $
 */
public abstract class PDFont implements COSObjectable
{

    /**
     * The cos dictionary for this font.
     */
    protected COSDictionary font;

    /**
     * This is only used if this is a font object and it has an encoding.
     */
    private Encoding fontEncoding = null;
    /**
     * This is only used if this is a font object and it has an encoding and it is
     * a type0 font with a cmap.
     */
    private CMap cmap = null;

    private static Map afmResources = null;
    private static Map cmapObjects = null;
    private static Map afmObjects = null;
    private static Map cmapSubstitutions = null;

    static
    {
        //these are read-only once they are created
        afmResources = new HashMap();
        cmapSubstitutions = new HashMap();
        
        //these are read-write
        cmapObjects = Collections.synchronizedMap( new HashMap() );
        afmObjects = Collections.synchronizedMap( new HashMap() );
        

        afmResources.put( COSName.getPDFName( "Courier-Bold" ), "Resources/afm/Courier-Bold.afm" );
        afmResources.put( COSName.getPDFName( "Courier-BoldOblique" ), "Resources/afm/Courier-BoldOblique.afm" );
        afmResources.put( COSName.getPDFName( "Courier" ), "Resources/afm/Courier.afm" );
        afmResources.put( COSName.getPDFName( "Courier-Oblique" ), "Resources/afm/Courier-Oblique.afm" );
        afmResources.put( COSName.getPDFName( "Helvetica" ), "Resources/afm/Helvetica.afm" );
        afmResources.put( COSName.getPDFName( "Helvetica-Bold" ), "Resources/afm/Helvetica-Bold.afm" );
        afmResources.put( COSName.getPDFName( "Helvetica-BoldOblique" ), "Resources/afm/Helvetica-BoldOblique.afm" );
        afmResources.put( COSName.getPDFName( "Helvetica-Oblique" ), "Resources/afm/Helvetica-Oblique.afm" );
        afmResources.put( COSName.getPDFName( "Symbol" ), "Resources/afm/Symbol.afm" );
        afmResources.put( COSName.getPDFName( "Times-Bold" ), "Resources/afm/Times-Bold.afm" );
        afmResources.put( COSName.getPDFName( "Times-BoldItalic" ), "Resources/afm/Times-BoldItalic.afm" );
        afmResources.put( COSName.getPDFName( "Times-Italic" ), "Resources/afm/Times-Italic.afm" );
        afmResources.put( COSName.getPDFName( "Times-Roman" ), "Resources/afm/Times-Roman.afm" );
        afmResources.put( COSName.getPDFName( "ZapfDingbats" ), "Resources/afm/ZapfDingbats.afm" );

        cmapSubstitutions.put( "ETen-B5-H", "ETen-B5-UCS2" );
        cmapSubstitutions.put( "ETen-B5-V", "ETen-B5-UCS2" );
        cmapSubstitutions.put( "ETenms-B5-H", "ETen-B5-UCS2" );
        cmapSubstitutions.put( "ETenms-B5-V", "ETen-B5-UCS2" );
        
        cmapSubstitutions.put( "90ms-RKSJ-H", "90ms-RKSJ-UCS2" );
        cmapSubstitutions.put( "90ms-RKSJ-V", "90ms-RKSJ-UCS2" );
        cmapSubstitutions.put( "90msp-RKSJ-H", "90ms-RKSJ-UCS2" );
        cmapSubstitutions.put( "90msp-RKSJ-V", "90ms-RKSJ-UCS2" );
        cmapSubstitutions.put( "GBK-EUC-H", "GBK-EUC-UCS2" );
        cmapSubstitutions.put( "GBK-EUC-V", "GBK-EUC-UCS2" );
        cmapSubstitutions.put( "GBpc-EUC-H", "GBpc-EUC-UCS2C" );
        cmapSubstitutions.put( "GBpc-EUC-V", "GBpc-EUC-UCS2C" );
        
        cmapSubstitutions.put( "UniJIS-UCS2-HW-H", "UniJIS-UCS2-H" );
    }

    /**
     * This will clear AFM resources that are stored statically.
     * This is usually not a problem unless you want to reclaim
     * resources for a long running process.
     *
     * SPECIAL NOTE: The font calculations are currently in COSObject, which
     * is where they will reside until PDFont is mature enough to take them over.
     * PDFont is the appropriate place for them and not in COSObject but we need font
     * calculations for text extractaion.  THIS METHOD WILL BE MOVED OR REMOVED
     * TO ANOTHER LOCATION IN A FUTURE VERSION OF PDFBOX.
     */
    public static void clearResources()
    {
        afmObjects.clear();
        cmapObjects.clear();
    }

    /**
     * Constructor.
     */
    public PDFont()
    {
        font = new COSDictionary();
        font.setItem( COSName.TYPE, COSName.FONT );
    }

    /**
     * Constructor.
     *
     * @param fontDictionary The font dictionary according to the PDF specification.
     */
    public PDFont( COSDictionary fontDictionary )
    {
        font = fontDictionary;
    }

    /**
     * {@inheritDoc}
     */
    public COSBase getCOSObject()
    {
        return font;
    }

    /**
     * This will get the font width for a character.
     *
     * @param c The character code to get the width for.
     * @param offset The offset into the array.
     * @param length The length of the data.
     *
     * @return The width is in 1000 unit of text space, ie 333 or 777
     *
     * @throws IOException If an error occurs while parsing.
     */
    public abstract float getFontWidth( byte[] c, int offset, int length ) throws IOException;
    
    /**
     * This will get the font width for a character.
     *
     * @param c The character code to get the width for.
     * @param offset The offset into the array.
     * @param length The length of the data.
     *
     * @return The width is in 1000 unit of text space, ie 333 or 777
     *
     * @throws IOException If an error occurs while parsing.
     */
    public abstract float getFontHeight( byte[] c, int offset, int length ) throws IOException;

    /**
     * This will get the width of this string for this font.
     *
     * @param string The string to get the width of.
     *
     * @return The width of the string in 1000 units of text space, ie 333 567...
     *
     * @throws IOException If there is an error getting the width information.
     */
    public float getStringWidth( String string ) throws IOException
    {
        byte[] data = string.getBytes();
        float totalWidth = 0;
        for( int i=0; i<data.length; i++ )
        {
            totalWidth+=getFontWidth( data, i, 1 );
        }
        return totalWidth;
    }

    /**
     * This will get the average font width for all characters.
     *
     * @return The width is in 1000 unit of text space, ie 333 or 777
     *
     * @throws IOException If an error occurs while parsing.
     */
    public abstract float getAverageFontWidth() throws IOException;

    /**
     * This will draw a string on a canvas using the font.
     *
     * @param string The string to draw.
     * @param g The graphics to draw onto.
     * @param fontSize The size of the font to draw.
     * @param xScale The x scaling percent.
     * @param yScale The y scaling percent.
     * @param x The x coordinate to draw at.
     * @param y The y coordinate to draw at.
     *
     * @throws IOException If there is an error drawing the specific string.
     */
    public abstract void drawString( String string, Graphics g, float fontSize, 
        float xScale, float yScale, float x, float y ) throws IOException;

    /**
     * Used for multibyte encodings.
     *
     * @param data The array of data.
     * @param offset The offset into the array.
     * @param length The number of bytes to use.
     *
     * @return The int value of data from the array.
     */
    protected int getCodeFromArray( byte[] data, int offset, int length )
    {
        int code = 0;
        for( int i=0; i<length; i++ )
        {
            code <<= 8;
            code |= (data[offset+i]+256)%256;
        }
        return code;
    }

    /**
     * This will attempt to get the font width from an AFM file.
     *
     * @param code The character code we are trying to get.
     *
     * @return The font width from the AFM file.
     *
     * @throws IOException if we cannot find the width.
     */
    protected float getFontWidthFromAFMFile( int code ) throws IOException
    {