A persistent tree map (work in progress).

h2/src/tools/org/h2/dev/store/btree/BtreeMap.java

@@ -22,38 +22,28 @@ public class BtreeMap<K, V> {
     private final DataType valueType;
     private Page root;
 
-    private BtreeMap(BtreeMapStore store, String name, Class<K> keyClass, Class<V> valueClass) {
+    private BtreeMap(BtreeMapStore store, String name, DataType keyType, DataType valueType) {
         this.store = store;
         this.name = name;
-        if (keyClass == Integer.class) {
-            keyType = new IntegerType();
-        } else if (keyClass == String.class) {
-            keyType = new StringType();
-        } else {
-            throw new RuntimeException("Unsupported key class " + keyClass.toString());
-        }
-        if (valueClass == Integer.class) {
-            valueType = new IntegerType();
-        } else if (valueClass == String.class) {
-            valueType = new StringType();
-        } else {
-            throw new RuntimeException("Unsupported value class " + keyClass.toString());
-        }
+        this.keyType = keyType;
+        this.valueType = valueType;
     }
 
     /**
-     * Get the class with the given tag name.
+     * Open a map.
      *
-     * @param name the tag name
-     * @return the class
+     * @param <K> the key type
+     * @param <V> the value type
+     * @param store the tree store
+     * @param name the name of the map
+     * @param keyClass the key class
+     * @param valueClass the value class
+     * @return the map
      */
-    static Class<?> getClass(String name) {
-        if (name.equals("i")) {
-            return Integer.class;
-        } else if (name.equals("s")) {
-            return String.class;
-        }
-        throw new RuntimeException("Unknown class name " + name);
+    static <K, V> BtreeMap<K, V> open(BtreeMapStore store, String name, Class<K> keyClass, Class<V> valueClass) {
+        DataType keyType = DataTypeFactory.getDataType(keyClass);
+        DataType valueType = DataTypeFactory.getDataType(valueClass);
+        return new BtreeMap<K, V>(store, name, keyType, valueType);
     }
 
     /**
@@ -67,8 +57,8 @@ public class BtreeMap<K, V> {
      * @param valueClass the value class
      * @return the map
      */
-    static <K, V> BtreeMap<K, V> open(BtreeMapStore store, String name, Class<K> keyClass, Class<V> valueClass) {
-        return new BtreeMap<K, V>(store, name, keyClass, valueClass);
+    static <K, V> BtreeMap<K, V> open(BtreeMapStore store, String name, DataType keyType, DataType valueType) {
+        return new BtreeMap<K, V>(store, name, keyType, valueType);
     }
 
     /**

h2/src/tools/org/h2/dev/store/btree/BtreeMapStore.java

@@ -513,8 +513,8 @@ public class BtreeMapStore {
                 continue;
             }
             String[] d = StringUtils.arraySplit(v, ',', false);
-            Class<?> kt = BtreeMap.getClass(d[1]);
-            Class<?> vt = BtreeMap.getClass(d[2]);
+            DataType kt = DataTypeFactory.getDataType(d[1]);
+            DataType vt = DataTypeFactory.getDataType(d[2]);
             BtreeMap<?, ?> oldData = BtreeMap.open(this, "old-" + k, kt, vt);
             long oldDataRoot = Long.parseLong(d[0]);
             if (oldDataRoot == 0) {

h2/src/tools/org/h2/dev/store/btree/DataTypeFactory.java

+/*
+ * Copyright 2004-2011 H2 Group. Multiple-Licensed under the H2 License,
+ * Version 1.0, and under the Eclipse Public License, Version 1.0
+ * (http://h2database.com/html/license.html).
+ * Initial Developer: H2 Group
+ */
+package org.h2.dev.store.btree;
+
+/**
+ * A factory for data types.
+ */
+public class DataTypeFactory {
+
+    /**
+     * Get the class with the given name.
+     *
+     * @param name the name
+     * @return the data type
+     */
+    static DataType getDataType(String name) {
+        if (name.equals("i")) {
+            return new IntegerType();
+        } else if (name.equals("s")) {
+            return new StringType();
+        }
+        throw new RuntimeException("Unknown data type name " + name);
+    }
+
+    /**
+     * Get the data type object for the given class.
+     *
+     * @param objectClass the class
+     * @return the data type object
+     */
+    static DataType getDataType(Class<?> objectClass) {
+        if (objectClass == Integer.class) {
+            return new IntegerType();
+        } else if (objectClass == String.class) {
+            return new StringType();
+        }
+        throw new RuntimeException("Unsupported object class " + objectClass.toString());
+    }
+
+}