| /* |
| * 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 org.apache.pirk.schema.data; |
| |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.Set; |
| |
| /** |
| * The data schema registry is a global location for data schema descriptors. |
| * |
| * @see DataSchema |
| * @see DataSchemaLoader |
| */ |
| public class DataSchemaRegistry |
| { |
| // The registry. Maps schema name to data schema. |
| private static final Map<String,DataSchema> registry = new HashMap<>(); |
| |
| // Not designed to be instantiated. |
| DataSchemaRegistry() |
| { |
| |
| } |
| |
| /** |
| * Adds the given data schema to the registry. |
| * |
| * If there was an existing schema with the same name, it is replaced. |
| * |
| * @param schema |
| * The data schema to add. |
| * @return the previous schema registered at the same name, or <code>null</code> if there were none. |
| */ |
| public static DataSchema put(DataSchema schema) |
| { |
| return registry.put(schema.getSchemaName(), schema); |
| } |
| |
| /** |
| * Returns the data schema with the given name. |
| * |
| * @param schemaName |
| * The data schema name to be returned. |
| * @return The data schema, or <code>null</code> if no such schema. |
| */ |
| public static DataSchema get(String schemaName) |
| { |
| return registry.get(schemaName); |
| } |
| |
| /** |
| * Returns the set of data schema names held in the registry. |
| * |
| * @return The possibly empty set of data schema names. |
| */ |
| public static Set<String> getNames() |
| { |
| return registry.keySet(); |
| } |
| |
| /** |
| * Clear the registry |
| */ |
| public static void clearRegistry() |
| { |
| registry.clear(); |
| } |
| } |