1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache license, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the license for the specific language governing permissions and 15 * limitations under the license. 16 */ 17 package org.apache.logging.log4j.nosql.appender; 18 19 import java.io.Closeable; 20 21 /** 22 * Represents a connection to the NoSQL database. Serves as a factory for new (empty) objects and an endpoint for 23 * inserted objects. 24 * 25 * @param <T> Specifies which implementation of {@link NoSqlObject} this connection provides. 26 * @param <W> Specifies which type of database object is wrapped by the {@link NoSqlObject} implementation provided. 27 */ 28 public interface NoSqlConnection<W, T extends NoSqlObject<W>> extends Closeable { 29 /** 30 * Instantiates and returns a {@link NoSqlObject} instance whose properties can be configured before ultimate 31 * insertion via {@link #insertObject(NoSqlObject)}. 32 * 33 * @return a new object. 34 * @see NoSqlObject 35 */ 36 T createObject(); 37 38 /** 39 * Creates an array of the specified length typed to match the {@link NoSqlObject} implementation appropriate for 40 * this provider. 41 * 42 * @param length the length of the array to create. 43 * @return a new array. 44 * @see NoSqlObject 45 */ 46 T[] createList(int length); 47 48 /** 49 * Inserts the given object into the underlying NoSQL database. 50 * 51 * @param object The object to insert. 52 */ 53 void insertObject(NoSqlObject<W> object); 54 55 /** 56 * Closes the underlying connection. This method call should be idempotent. Only the first call should have any 57 * effect; all further calls should be ignored. It's possible the underlying connection is stateless (such as an 58 * HTTP web service), in which case this method would be a no-op. This method should also commit any open 59 * transactions, if applicable and if not already committed. 60 * <p> 61 * If this connection is part of a connection pool, executing this method should commit the transaction and return 62 * the connection to the pool, but it should not actually close the underlying connection. 63 * </p> 64 */ 65 @Override 66 void close(); 67 68 /** 69 * Indicates whether the underlying connection is closed. If the underlying connection is stateless (such as an 70 * HTTP web service), this method would likely always return true. Essentially, this method should only return 71 * {@code true} if a call to {@link #insertObject(NoSqlObject)} <b>will</b> fail due to the state of this object. 72 * 73 * @return {@code true} if this object is considered closed. 74 */ 75 boolean isClosed(); 76 }