1 package org.eclipse.aether.spi.log; 2 3 /* 4 * Licensed to the Apache Software Foundation (ASF) under one 5 * or more contributor license agreements. See the NOTICE file 6 * distributed with this work for additional information 7 * regarding copyright ownership. The ASF licenses this file 8 * to you under the Apache License, Version 2.0 (the 9 * "License"); you may not use this file except in compliance 10 * with the License. You may obtain a copy of the License at 11 * 12 * http://www.apache.org/licenses/LICENSE-2.0 13 * 14 * Unless required by applicable law or agreed to in writing, 15 * software distributed under the License is distributed on an 16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 17 * KIND, either express or implied. See the License for the 18 * specific language governing permissions and limitations 19 * under the License. 20 */ 21 22 /** 23 * A logger factory that disables any logging. 24 */ 25 public final class NullLoggerFactory 26 implements LoggerFactory 27 { 28 29 /** 30 * The singleton instance of this factory. 31 */ 32 public static final LoggerFactory INSTANCE = new NullLoggerFactory(); 33 34 /** 35 * The singleton logger used by this factory. 36 */ 37 public static final Logger LOGGER = new NullLogger(); 38 39 public Logger getLogger( String name ) 40 { 41 return LOGGER; 42 } 43 44 private NullLoggerFactory() 45 { 46 // hide constructor 47 } 48 49 /** 50 * Gets a logger from the specified factory for the given class, falling back to a logger from this factory if the 51 * specified factory is {@code null} or fails to provide a logger. 52 * 53 * @param loggerFactory The logger factory from which to get the logger, may be {@code null}. 54 * @param type The class for which to get the logger, must not be {@code null}. 55 * @return The requested logger, never {@code null}. 56 */ 57 public static Logger getSafeLogger( LoggerFactory loggerFactory, Class<?> type ) 58 { 59 if ( loggerFactory == null ) 60 { 61 return LOGGER; 62 } 63 Logger logger = loggerFactory.getLogger( type.getName() ); 64 if ( logger == null ) 65 { 66 return LOGGER; 67 } 68 return logger; 69 } 70 71 }