src/java/org/apache/poi/hssf/usermodel/StaticFontMetrics.java

   1 /* ====================================================================
   2    Licensed to the Apache Software Foundation (ASF) under one or more
   3    contributor license agreements.  See the NOTICE file distributed with
   4    this work for additional information regarding copyright ownership.
   5    The ASF licenses this file to You under the Apache License, Version 2.0
   6    (the "License"); you may not use this file except in compliance with
   7    the License.  You may obtain a copy of the License at
   8
   9        http://www.apache.org/licenses/LICENSE-2.0
  10
  11    Unless required by applicable law or agreed to in writing, software
  12    distributed under the License is distributed on an "AS IS" BASIS,
  13    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  14    See the License for the specific language governing permissions and
  15    limitations under the License.
  16 ==================================================================== */
  17
  18 package org.apache.poi.hssf.usermodel;
  19
  20 import java.util.*;
  21 import java.awt.*;
  22 import java.io.*;
  23
  24 /**
  25  * Allows the user to lookup the font metrics for a particular font without
  26  * actually having the font on the system.  The font details are loaded
  27  * as a resource from the POI jar file (or classpath) and should be contained
  28  * in path "/font_metrics.properties".  The font widths are for a 10 point
  29  * version of the font.  Use a multiplier for other sizes.
  30  *
  31  * @author Glen Stampoultzis (glens at apache.org)
  32  */
  33 class StaticFontMetrics
  34 {
  35         /** The font metrics property file we're using */
  36     private static Properties fontMetricsProps;
  37         /** Our cache of font details we've already looked up */
  38     private static Map fontDetailsMap = new HashMap();
  39
  40     /**
  41      * Retrieves the fake font details for a given font.
  42      * @param font  the font to lookup.
  43      * @return  the fake font.
  44      */
  45     public static FontDetails getFontDetails(Font font)
  46     {
  47                 // If we haven't already identified out font metrics file,
  48                 //  figure out which one to use and load it
  49         if (fontMetricsProps == null)
  50         {
  51             InputStream metricsIn = null;
  52             try
  53             {
  54                 fontMetricsProps = new Properties();
  55
  56                 // Check to see if the font metric file was specified
  57                 //  as a system property
  58                 String propFileName = null;
  59                 try {
  60                     propFileName = System.getProperty("font.metrics.filename");
  61                 } catch(SecurityException e) {}
  62
  63                 if (propFileName != null) {
  64                     File file = new File(propFileName);
  65                     if (!file.exists())
  66                         throw new FileNotFoundException("font_metrics.properties not found at path " + file.getAbsolutePath());
  67                     metricsIn = new FileInputStream(file);
  68                 }
  69                 else {
  70                     // Use the built-in font metrics file off the classpath
  71                     metricsIn = FontDetails.class.getResourceAsStream("/font_metrics.properties");
  72                     if (metricsIn == null)
  73                         throw new FileNotFoundException("font_metrics.properties not found in classpath");
  74                 }
  75                 fontMetricsProps.load(metricsIn);
  76             }
  77             catch ( IOException e )
  78             {
  79                 throw new RuntimeException("Could not load font metrics: " + e.getMessage());
  80             }
  81             finally
  82             {
  83                 if (metricsIn != null)
  84                 {
  85                     try
  86                     {
  87                         metricsIn.close();
  88                     }
  89                     catch ( IOException ignore ) { }
  90                 }
  91             }
  92         }
  93
  94                 // Grab the base name of the font they've asked about
  95         String fontName = font.getName();
  96
  97                 // Some fonts support plain/bold/italic/bolditalic variants
  98                 // Others have different font instances for bold etc
  99                 // (eg font.dialog.plain.* vs font.Californian FB Bold.*)
 100                 String fontStyle = "";
 101                 if(font.isPlain())  fontStyle += "plain";
 102                 if(font.isBold())   fontStyle += "bold";
 103                 if(font.isItalic()) fontStyle += "italic";
 104
 105                 // Do we have a definition for this font with just the name?
 106                 // If not, check with the font style added
 107                 if(fontMetricsProps.get(FontDetails.buildFontHeightProperty(fontName)) == null &&
 108                 fontMetricsProps.get(FontDetails.buildFontHeightProperty(fontName+"."+fontStyle)) != null) {
 109                         // Need to add on the style to the font name
 110                         fontName += "." + fontStyle;
 111                 }
 112
 113                 // Get the details on this font
 114         if (fontDetailsMap.get(fontName) == null) {
 115             FontDetails fontDetails = FontDetails.create(fontName, fontMetricsProps);
 116             fontDetailsMap.put( fontName, fontDetails );
 117             return fontDetails;
 118         } else {
 119             return (FontDetails) fontDetailsMap.get(fontName);
 120         }
 121
 122     }
 123 }