001/** 002 * Logback: the reliable, generic, fast and flexible logging framework. 003 * Copyright (C) 1999-2002, QOS.ch. All rights reserved. 004 * 005 * This program and the accompanying materials are dual-licensed under 006 * either the terms of the Eclipse Public License v1.0 as published by 007 * the Eclipse Foundation 008 * 009 * or (per the licensee's choosing) 010 * 011 * under the terms of the GNU Lesser General Public License version 2.1 012 * as published by the Free Software Foundation. 013 */ 014package ch.qos.logback.core.sift; 015 016import java.util.stream.Stream; 017 018import ch.qos.logback.core.Context; 019import ch.qos.logback.core.CoreConstants; 020import ch.qos.logback.core.model.AppenderModel; 021import ch.qos.logback.core.model.Model; 022import ch.qos.logback.core.model.SiftModel; 023import ch.qos.logback.core.model.processor.ModelHandlerBase; 024import ch.qos.logback.core.model.processor.ModelHandlerException; 025import ch.qos.logback.core.model.processor.ModelInterpretationContext; 026 027public class SiftModelHandler extends ModelHandlerBase { 028 final static String ONE_AND_ONLY_ONE_URL = CoreConstants.CODES_URL + "#1andOnly1"; 029 030 public SiftModelHandler(Context context) { 031 super(context); 032 } 033 034 static public SiftModelHandler makeInstance(Context context, ModelInterpretationContext ic) { 035 return new SiftModelHandler(context); 036 } 037 038 @Override 039 protected Class<SiftModel> getSupportedModelClass() { 040 return SiftModel.class; 041 } 042 043 @SuppressWarnings("unchecked") 044 @Override 045 public void handle(ModelInterpretationContext mic, Model model) throws ModelHandlerException { 046 047 SiftModel siftModel = (SiftModel) model; 048 // don't let the processor handle sub-models 049 siftModel.markAsSkipped(); 050 051 long appenderModelCount = computeAppenderModelCount(siftModel); 052 053 if(appenderModelCount == 0) { 054 String errMsg = "No nested appenders found within the <sift> element in SiftingAppender."; 055 addError(errMsg); 056 return; 057 } 058 if(appenderModelCount > 1) { 059 String errMsg = "Only and only one appender can be nested the <sift> element in SiftingAppender. See also " + ONE_AND_ONLY_ONE_URL; 060 addError(errMsg); 061 return; 062 } 063 064 065 Object o = mic.peekObject(); 066 if (o instanceof SiftingAppenderBase) { 067 @SuppressWarnings("rawtypes") 068 SiftingAppenderBase sa = (SiftingAppenderBase) o; 069 070 String key = sa.getDiscriminatorKey(); 071 @SuppressWarnings("rawtypes") 072 AppenderFactoryUsingSiftModel afusm = new AppenderFactoryUsingSiftModel(mic, siftModel, key); 073 074 sa.setAppenderFactory(afusm); 075 076 } else { 077 addError("Unexpected object "+ o); 078 } 079 } 080 081 private long computeAppenderModelCount(SiftModel siftModel) { 082 Stream<Model> stream = siftModel.getSubModels().stream(); 083 long count = stream.filter((Model m) -> m instanceof AppenderModel).count(); 084 return count; 085 } 086 087}