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.model.processor;
015
016import ch.qos.logback.core.Context;
017import ch.qos.logback.core.joran.action.ImcplicitActionDataForBasicProperty;
018import ch.qos.logback.core.joran.action.ImplicitModelData;
019import ch.qos.logback.core.joran.action.ImplicitModelDataForComplexProperty;
020import ch.qos.logback.core.joran.spi.NoAutoStartUtil;
021import ch.qos.logback.core.joran.util.PropertySetter;
022import ch.qos.logback.core.joran.util.beans.BeanDescriptionCache;
023import ch.qos.logback.core.model.ComponentModel;
024import ch.qos.logback.core.model.ImplicitModel;
025import ch.qos.logback.core.model.Model;
026import ch.qos.logback.core.model.ModelConstants;
027import ch.qos.logback.core.spi.ContextAware;
028import ch.qos.logback.core.spi.LifeCycle;
029import ch.qos.logback.core.util.AggregationType;
030import ch.qos.logback.core.util.Loader;
031import ch.qos.logback.core.util.OptionHelper;
032
033public class ImplicitModelHandler extends ModelHandlerBase {
034
035    private final BeanDescriptionCache beanDescriptionCache;
036    private ImplicitModelData implicitModelData;
037
038    static public final String IGNORING_UNKNOWN_PROP = "Ignoring unknown property";
039
040    boolean inError = false;
041
042    public ImplicitModelHandler(Context context, BeanDescriptionCache beanDescriptionCache) {
043        super(context);
044        this.beanDescriptionCache = beanDescriptionCache;
045    }
046
047    protected Class<? extends ImplicitModel> getSupportedModelClass() {
048        return ImplicitModel.class;
049    }
050
051    static public ImplicitModelHandler makeInstance(Context context, ModelInterpretationContext mic) {
052        BeanDescriptionCache beanDescriptionCache = mic.getBeanDescriptionCache();
053        return new ImplicitModelHandler(context, beanDescriptionCache);
054    }
055
056    @Override
057    public void handle(ModelInterpretationContext mic, Model model) {
058
059        ImplicitModel implicitModel = (ImplicitModel) model;
060
061        // calling intercon.peekObject with an empty stack will throw an exception
062        if (mic.isObjectStackEmpty()) {
063            inError = true;
064            return;
065        }
066        String nestedElementTagName = implicitModel.getTag();
067
068        Object o = mic.peekObject();
069        PropertySetter parentBean = new PropertySetter(beanDescriptionCache, o);
070        parentBean.setContext(context);
071
072        AggregationType aggregationType = parentBean.computeAggregationType(nestedElementTagName);
073
074        switch (aggregationType) {
075        case NOT_FOUND:
076            addWarn(IGNORING_UNKNOWN_PROP+" [" + nestedElementTagName + "] in [" + o.getClass().getName() + "]");
077            inError = true;
078            // no point in processing submodels
079            implicitModel.markAsSkipped();
080            return;
081        case AS_BASIC_PROPERTY:
082        case AS_BASIC_PROPERTY_COLLECTION:
083            ImcplicitActionDataForBasicProperty adBasicProperty = new ImcplicitActionDataForBasicProperty(parentBean,
084                    aggregationType, nestedElementTagName);
085            implicitModelData = adBasicProperty;
086            doBasicProperty(mic, model, adBasicProperty);
087            return;
088        // we only push action data if NestComponentIA is applicable
089        case AS_COMPLEX_PROPERTY_COLLECTION:
090        case AS_COMPLEX_PROPERTY:
091            ImplicitModelDataForComplexProperty adComplex = new ImplicitModelDataForComplexProperty(parentBean,
092                    aggregationType, nestedElementTagName);
093            implicitModelData = adComplex;
094            doComplex(mic, implicitModel, adComplex);
095            return;
096        default:
097            addError("PropertySetter.computeAggregationType returned " + aggregationType);
098            return;
099        }
100
101    }
102
103    void doBasicProperty(ModelInterpretationContext interpretationContext, Model model,
104            ImcplicitActionDataForBasicProperty actionData) {
105        String finalBody = interpretationContext.subst(model.getBodyText());
106        // get the action data object pushed in isApplicable() method call
107        // IADataForBasicProperty actionData = (IADataForBasicProperty)
108        // actionDataStack.peek();
109        switch (actionData.aggregationType) {
110        case AS_BASIC_PROPERTY:
111            actionData.parentBean.setProperty(actionData.propertyName, finalBody);
112            break;
113        case AS_BASIC_PROPERTY_COLLECTION:
114            actionData.parentBean.addBasicProperty(actionData.propertyName, finalBody);
115            break;
116        default:
117            addError("Unexpected aggregationType " + actionData.aggregationType);
118        }
119    }
120
121    public void doComplex(ModelInterpretationContext interpretationContext, ComponentModel componentModel,
122            ImplicitModelDataForComplexProperty actionData) {
123
124        String className = componentModel.getClassName();
125        // perform variable name substitution
126        String substClassName = interpretationContext.subst(className);
127
128        String fqcn = interpretationContext.getImport(substClassName);
129
130        Class<?> componentClass = null;
131        try {
132
133            if (!OptionHelper.isNullOrEmptyOrAllSpaces(fqcn)) {
134                componentClass = Loader.loadClass(fqcn, context);
135            } else {
136                // guess class name via implicit rules
137                PropertySetter parentBean = actionData.parentBean;
138                componentClass = parentBean.getClassNameViaImplicitRules(actionData.propertyName,
139                        actionData.getAggregationType(), interpretationContext.getDefaultNestedComponentRegistry());
140            }
141
142            if (componentClass == null) {
143                actionData.inError = true;
144                String errMsg = "Could not find an appropriate class for property [" + componentModel.getTag() + "]";
145                addError(errMsg);
146                return;
147            }
148
149            if (OptionHelper.isNullOrEmptyOrAllSpaces(fqcn)) {
150                addInfo("Assuming default type [" + componentClass.getName() + "] for [" + componentModel.getTag()
151                        + "] property");
152            }
153
154            actionData.setNestedComplexProperty(componentClass.getConstructor().newInstance());
155
156            // pass along the repository
157            if (actionData.getNestedComplexProperty() instanceof ContextAware) {
158                ((ContextAware) actionData.getNestedComplexProperty()).setContext(this.context);
159            }
160            // addInfo("Pushing component [" + localName
161            // + "] on top of the object stack.");
162            interpretationContext.pushObject(actionData.getNestedComplexProperty());
163
164        } catch (Exception oops) {
165            actionData.inError = true;
166            String msg = "Could not create component [" + componentModel.getTag() + "] of type [" + fqcn + "]";
167            addError(msg, oops);
168        }
169    }
170
171    @Override
172    public void postHandle(ModelInterpretationContext intercon, Model model) {
173        if (inError) {
174            return;
175        }
176
177        if(implicitModelData == null)
178            return;
179        
180        // the action data can in an incorrect state, in which case we need to 
181        // disengage
182        if(implicitModelData.inError) {
183            return;
184        }
185        if (implicitModelData instanceof ImplicitModelDataForComplexProperty) {
186            postHandleComplex(intercon, model, (ImplicitModelDataForComplexProperty) implicitModelData);
187        }
188
189    }
190
191    private void postHandleComplex(ModelInterpretationContext mic, Model model,
192            ImplicitModelDataForComplexProperty imdComplex) {
193
194        PropertySetter nestedBean = new PropertySetter(beanDescriptionCache,
195                imdComplex.getNestedComplexProperty());
196        nestedBean.setContext(context);
197
198        // have the nested element point to its parent if possible
199        if (nestedBean.computeAggregationType(ModelConstants.PARENT_PROPPERTY_KEY) == AggregationType.AS_COMPLEX_PROPERTY) {
200            nestedBean.setComplexProperty(ModelConstants.PARENT_PROPPERTY_KEY, imdComplex.parentBean.getObj());
201        }
202
203        // start the nested complex property if it implements LifeCycle and is not
204        // marked with a @NoAutoStart annotation
205        Object nestedComplexProperty = imdComplex.getNestedComplexProperty();
206        if (NoAutoStartUtil.shouldBeStarted(nestedComplexProperty)) {
207            ((LifeCycle) nestedComplexProperty).start();
208        }
209
210        Object o = mic.peekObject();
211
212        if (o != imdComplex.getNestedComplexProperty()) {
213            addError("The object on the top the of the stack is not the component pushed earlier.");
214        } else {
215            mic.popObject();
216            // Now let us attach the component
217            switch (imdComplex.aggregationType) {
218            case AS_COMPLEX_PROPERTY:
219                imdComplex.parentBean.setComplexProperty(model.getTag(), imdComplex.getNestedComplexProperty());
220
221                break;
222            case AS_COMPLEX_PROPERTY_COLLECTION:
223                imdComplex.parentBean.addComplexProperty(model.getTag(), imdComplex.getNestedComplexProperty());
224                break;
225            default:
226                addError("Unexpected aggregationType " + imdComplex.aggregationType);
227            }
228        }
229    }
230
231}