fop/src/org/apache/fop/layout/hyphenation/Hyphenator.java

/* $Id$
 * Copyright (C) 2001 The Apache Software Foundation. All rights reserved.
 * For details on use and redistribution please refer to the
 * LICENSE file included with these sources.
 */

package org.apache.fop.layout.hyphenation;

import java.io.*;
import java.util.Hashtable;
import org.apache.fop.configuration.*;
import org.apache.fop.messaging.MessageHandler;

/**
 * This class is the main entry point to the hyphenation package.
 * You can use only the static methods or create an instance.
 *
 * @author Carlos Villegas <cav@uniscope.co.jp>
 */
public class Hyphenator {
    static Hashtable hyphenTrees = new Hashtable();

    private HyphenationTree hyphenTree = null;
    private int remainCharCount = 2;
    private int pushCharCount = 2;
    private static boolean errorDump = false;

    public Hyphenator(String lang, String country, int leftMin,
                      int rightMin) {
        hyphenTree = getHyphenationTree(lang, country);
        remainCharCount = leftMin;
        pushCharCount = rightMin;
    }

    public static HyphenationTree getHyphenationTree(String lang,
            String country) {
        String key = lang;
        //check whether the country code has been used
        if (country != null && !country.equals("none"))
            key += "_" + country;
        // first try to find it in the cache
        if (hyphenTrees.containsKey(key))
            return (HyphenationTree) hyphenTrees.get(key);
        if (hyphenTrees.containsKey(lang))
            return (HyphenationTree) hyphenTrees.get(lang);

        HyphenationTree hTree = getFopHyphenationTree(key);
        if (hTree == null) {
            String hyphenDir = Configuration.getStringValue("hyphenation-dir");
            if (hyphenDir != null){
                hTree = getUserHyphenationTree(key,hyphenDir);
            }
        }
        //put it into the pattern cache 
        if (hTree != null) {
            hyphenTrees.put(key, hTree);
        } else {
            MessageHandler.errorln("Couldn't find hyphenation pattern " + key);
        }
        return hTree;
    }

    public static HyphenationTree getFopHyphenationTree (String key) {
        HyphenationTree hTree = null;
        ObjectInputStream ois = null;
        InputStream is = null;
        try {
            is = Hyphenator.class.getResourceAsStream("/hyph/" + key + ".hyp");
            if (is == null) {
                if (key.length() == 5) {
                    is = Hyphenator.class.getResourceAsStream("/hyph/" +
                        key.substring(0,2) + ".hyp"); 
                    if (is != null) {
                        MessageHandler.errorln(
                          "Couldn't find hyphenation pattern  " + key
                           + "\nusing general language pattern " +
                           key.substring(0,2) + " instead.");
                    } else {
                    if (errorDump){
                        MessageHandler.errorln("Couldn't find precompiled " 
                        + "fop hyphenation pattern " + key + ".hyp");
                    }
                        return null;
                    }
                } else {
                    if (errorDump){
                        MessageHandler.errorln("Couldn't find precompiled " 
                        + "fop hyphenation pattern " + key + ".hyp");
                    }
                    return null;
                }
            }
            ois = new ObjectInputStream(is);
            hTree = (HyphenationTree) ois.readObject();
        } catch (Exception e) {
            e.printStackTrace();
        } finally { 
            if (ois != null) {
                try {
                    ois.close();
                } catch (IOException e) {
                    MessageHandler.errorln("can't close hyphenation object stream");
                }
            }
        } 
        return hTree;
    }

    /**
     *       load tree from serialized file or xml file
     *       using configuration settings
     */
    public static HyphenationTree getUserHyphenationTree (String key,String hyphenDir) {
        HyphenationTree hTree = null;
        // I use here the following convention. The file name specified in
        // the configuration is taken as the base name. First we try
        // name + ".hyp" assuming a serialized HyphenationTree. If that fails
        // we try name + ".xml", assumming a raw hyphenation pattern file.

        // first try serialized object
        File hyphenFile = new File(hyphenDir, key + ".hyp");
        if (hyphenFile.exists()) {
            ObjectInputStream ois = null;
            try {
                ois = new ObjectInputStream(
                        new FileInputStream(hyphenFile));
                hTree = (HyphenationTree) ois.readObject();
            } catch (Exception e) {
                e.printStackTrace();
            } finally { 
                if (ois != null) {
                    try {
                        ois.close();
                    } catch (IOException e) { 
                    }
                }
            } 
            return hTree;
        } else {

        // try the raw XML file
            hyphenFile = new File(hyphenDir, key + ".xml");
            if (hyphenFile.exists()) {
                hTree = new HyphenationTree();
                if (errorDump) {
                    MessageHandler.errorln("reading " +
                                           hyphenDir + key +".xml");
                }
                try {
                    hTree.loadPatterns(hyphenFile.getPath());
                    if (errorDump) {
                        System.out.println("Stats: ");
                        hTree.printStats();
                    }
                    return hTree;
                } catch (HyphenationException ex) {
                    if (errorDump) {
                        MessageHandler.errorln("Can't load user patterns "
                                                + "from xml file " + hyphenDir + key +".xml");
                    }
                    return null;
                }
            } else {
                if (errorDump) {
                    MessageHandler.errorln("Tried to load " +
                                       hyphenFile.toString() +
                                       "\nCannot find compiled nor xml file for " 
                                       + "hyphenation pattern" + key );
                }
                return null;
            }
        }
    }

    public static Hyphenation hyphenate(String lang, String country,
                                        String word, int leftMin, int rightMin) {
        HyphenationTree hTree = getHyphenationTree(lang, country);
        if (hTree == null) {
            MessageHandler.errorln(
              "Error building hyphenation tree for language " + lang);
            return null;
        }
        return hTree.hyphenate(word, leftMin, rightMin);
    }

    public static Hyphenation hyphenate(String lang, String country,
                                        char[] word, int offset, int len, int leftMin, int rightMin) {
        HyphenationTree hTree = getHyphenationTree(lang, country);
        if (hTree == null) {
            MessageHandler.errorln(
              "Error building hyphenation tree for language " + lang);
            return null;
        }
        return hTree.hyphenate(word, offset, len, leftMin, rightMin);
    }

    public void setMinRemainCharCount(int min) {
        remainCharCount = min;
    }

    public void setMinPushCharCount(int min) {
        pushCharCount = min;
    }

    public void setLanguage(String lang, String country) {
        hyphenTree = getHyphenationTree(lang, country);
    }

    public Hyphenation hyphenate(char[] word, int offset, int len) {
        if (hyphenTree == null)
            return null;
        return hyphenTree.hyphenate(word, offset, len, remainCharCount,
                                    pushCharCount);
    }

    public Hyphenation hyphenate(String word) {
        if (hyphenTree == null)
            return null;
        return hyphenTree.hyphenate(word, remainCharCount, pushCharCount);
    }
}