com.itextpdf.layout.hyphenation.HyphenationTreeCache Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.itextpdf.layout.hyphenation;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
/**
* This is a cache for HyphenationTree instances.
*/
public class HyphenationTreeCache {
/** Contains the cached hyphenation trees */
private Map hyphenTrees = new HashMap<>();
/** Used to avoid multiple error messages for the same language if a pattern file is missing. */
private Set missingHyphenationTrees;
/**
* Looks in the cache if a hyphenation tree is available and returns it if it is found.
* @param lang the language
* @param country the country (may be null or "none")
* @return the HyhenationTree instance or null if it's not in the cache
*/
public HyphenationTree getHyphenationTree(String lang, String country) {
String key = constructLlccKey(lang, country);
if (key == null) {
return null;
}
// first try to find it in the cache
if (hyphenTrees.containsKey(key)) {
return hyphenTrees.get(key);
} else if (hyphenTrees.containsKey(lang)) {
return hyphenTrees.get(lang);
} else {
return null;
}
}
/**
* Constructs the key for the hyphenation pattern file.
* @param lang the language
* @param country the country (may be null or "none")
* @return the resulting key
*/
public static String constructLlccKey(String lang, String country) {
String key = lang;
// check whether the country code has been used
if (country != null && !country.equals("none")) {
key += "_" + country;
}
return key;
}
/**
* If the user configured a hyphenation pattern file name
* for this (lang,country) value, return it. If not, return null.
* @param lang the language
* @param country the country (may be null or "none")
* @param hyphPatNames the map of user-configured hyphenation pattern file names
* @return the hyphenation pattern file name or null
*/
public static String constructUserKey(String lang, String country, Map hyphPatNames) {
String userKey = null;
if (hyphPatNames != null) {
String key = constructLlccKey(lang, country);
key = key.replace('_', '-');
userKey = hyphPatNames.get(key);
}
return userKey;
}
/**
* Cache a hyphenation tree under its key.
* @param key the key (ex. "de_CH" or "en")
* @param hTree the hyphenation tree
*/
public void cache(String key, HyphenationTree hTree) {
hyphenTrees.put(key, hTree);
}
/**
* Notes a key to a hyphenation tree as missing.
* This is to avoid searching a second time for a hyphenation pattern file which is not
* available.
* @param key the key (ex. "de_CH" or "en")
*/
public void noteMissing(String key) {
if (missingHyphenationTrees == null) {
missingHyphenationTrees = new HashSet<>();
}
missingHyphenationTrees.add(key);
}
/**
* Indicates whether a hyphenation file has been requested before but it wasn't available.
* This is to avoid searching a second time for a hyphenation pattern file which is not
* available.
* @param key the key (ex. "de_CH" or "en")
* @return true if the hyphenation tree is unavailable
*/
public boolean isMissing(String key) {
return (missingHyphenationTrees != null && missingHyphenationTrees.contains(key));
}
}