| /* |
| * Copyright (C) The Apache Software Foundation. All rights reserved. |
| * |
| * This software is published under the terms of the Apache Software |
| * License version 1.1, a copy of which has been included with this |
| * distribution in the LICENSE.txt file. |
| */ |
| |
| package org.apache.log4j.config; |
| |
| import java.beans.*; |
| import java.lang.reflect.*; |
| import org.apache.log4j.Priority; |
| import org.apache.log4j.helpers.LogLog; |
| |
| |
| /** |
| Used for inferring configuration information for a log4j's component. |
| |
| @author Anders Kristensen |
| */ |
| public class PropertyGetter { |
| protected static final Object[] NULL_ARG = new Object[] {}; |
| protected Object obj; |
| protected PropertyDescriptor[] props; |
| |
| public interface PropertyCallback { |
| void foundProperty(Object obj, String prefix, String name, Object value); |
| } |
| |
| /** |
| Create a new PropertyGetter for the specified Object. This is done |
| in prepartion for invoking {@link |
| #getProperties(PropertyGetter.PropertyCallback, String)} one or |
| more times. |
| |
| @param obj the object for which to set properties */ |
| public |
| PropertyGetter(Object obj) throws IntrospectionException { |
| BeanInfo bi = Introspector.getBeanInfo(obj.getClass()); |
| props = bi.getPropertyDescriptors(); |
| this.obj = obj; |
| } |
| |
| public |
| static |
| void getProperties(Object obj, PropertyCallback callback, String prefix) { |
| try { |
| new PropertyGetter(obj).getProperties(callback, prefix); |
| } catch (IntrospectionException ex) { |
| LogLog.error("Failed to introspect object " + obj, ex); |
| } |
| } |
| |
| public |
| void getProperties(PropertyCallback callback, String prefix) { |
| for (int i = 0; i < props.length; i++) { |
| Method getter = props[i].getReadMethod(); |
| if (getter == null) continue; |
| if (!isHandledType(getter.getReturnType())) { |
| //System.err.println("Ignoring " + props[i].getName() +" " + getter.getReturnType()); |
| continue; |
| } |
| String name = props[i].getName(); |
| try { |
| Object result = getter.invoke(obj, NULL_ARG); |
| //System.err.println("PROP " + name +": " + result); |
| if (result != null) { |
| callback.foundProperty(obj, prefix, name, result); |
| } |
| } catch (Exception ex) { |
| LogLog.warn("Failed to get value of property " + name); |
| } |
| } |
| } |
| |
| protected |
| boolean isHandledType(Class type) { |
| return String.class.isAssignableFrom(type) || |
| Integer.TYPE.isAssignableFrom(type) || |
| Long.TYPE.isAssignableFrom(type) || |
| Boolean.TYPE.isAssignableFrom(type) || |
| Priority.class.isAssignableFrom(type); |
| } |
| } |