1 files changed, 101 insertions, 0 deletions
diff --git a/src/java/org/apache/fop/hyphenation/HyphenationTreeCache.java b/src/java/org/apache/fop/hyphenation/HyphenationTreeCache.java
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+++ b/src/java/org/apache/fop/hyphenation/HyphenationTreeCache.java
@@ -0,0 +1,101 @@
+/*
+ * Copyright 2006 The Apache Software Foundation.
+ *
+ * Licensed 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.
+ */
+
+/* $Id$ */
+
+package org.apache.fop.hyphenation;
+
+import java.util.Hashtable;
+import java.util.Set;
+
+/**
+ * This is a cache for HyphenationTree instances.
+ */
+public class HyphenationTreeCache {
+
+    /** Contains the cached hyphenation trees */
+    private Hashtable hyphenTrees = new Hashtable();
+    /** 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 = constructKey(lang, country);
+        
+        // first try to find it in the cache
+        if (hyphenTrees.containsKey(key)) {
+            return (HyphenationTree)hyphenTrees.get(key);
+        } else if (hyphenTrees.containsKey(lang)) {
+            return (HyphenationTree)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 constructKey(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;
+    }
+    
+    /**
+     * 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 hyphneation 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 java.util.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 hyphneation 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));
+    }
+    
+}