| /* |
| * 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.cassandra.schema; |
| |
| import org.github.jamm.Unmetered; |
| |
| /** |
| * Encapsulates a volatile reference to an immutable {@link TableMetadata} instance. |
| * |
| * Used in classes that need up-to-date metadata to avoid the cost of looking up {@link Schema} hashmaps. |
| */ |
| @Unmetered |
| public final class TableMetadataRef |
| { |
| public final TableId id; |
| public final String keyspace; |
| public final String name; |
| |
| private volatile TableMetadata metadata; |
| private volatile TableMetadata localTableMetadata; |
| private volatile CompressionParams localCompressionParams; |
| |
| TableMetadataRef(TableMetadata metadata) |
| { |
| this.metadata = metadata; |
| |
| id = metadata.id; |
| keyspace = metadata.keyspace; |
| name = metadata.name; |
| } |
| |
| /** |
| * Create a new ref to the passed {@link TableMetadata} for use by offline tools only. |
| * |
| * @param metadata {@link TableMetadata} to reference |
| * @return a new TableMetadataRef instance linking to the passed {@link TableMetadata} |
| */ |
| public static TableMetadataRef forOfflineTools(TableMetadata metadata) |
| { |
| return new TableMetadataRef(metadata); |
| } |
| |
| public TableMetadata get() |
| { |
| return metadata; |
| } |
| |
| /** |
| * Returns node-local table metadata |
| */ |
| public TableMetadata getLocal() |
| { |
| if (this.localTableMetadata != null) |
| return localTableMetadata; |
| |
| return metadata; |
| } |
| |
| /** |
| * Update the reference with the most current version of {@link TableMetadata} |
| * <p> |
| * Must only be used by methods in {@link Schema}, *DO NOT* make public |
| * even for testing purposes, it isn't safe. |
| */ |
| void set(TableMetadata metadata) |
| { |
| metadata.validateCompatibility(get()); |
| this.metadata = metadata; |
| this.localTableMetadata = null; |
| } |
| |
| |
| public void setLocalOverrides(TableMetadata metadata) |
| { |
| metadata.validateCompatibility(get()); |
| this.localTableMetadata = metadata; |
| } |
| |
| @Override |
| public String toString() |
| { |
| return get().toString(); |
| } |
| } |