Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one * or more contributor license agreements. See the NOTICE file * distributed with this work for additional information * regarding copyright ownership. The ASF licenses this file * to you under the Apache License, Version 2.0 (the * "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, * software distributed under the License is distributed on an * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY * KIND, either express or implied. See the License for the * specific language governing permissions and limitations * under the License. */ package io.milton.property; import io.milton.annotations.BeanPropertyResource; import io.milton.annotations.BeanProperty; import io.milton.resource.Resource; import io.milton.http.exceptions.NotAuthorizedException; import io.milton.common.LogUtils; import java.beans.PropertyDescriptor; import java.lang.reflect.InvocationTargetException; import java.util.ArrayList; import java.util.List; import javax.xml.namespace.QName; import org.apache.commons.beanutils.PropertyUtils; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * A read/write source of properties which uses getter/setter style properties * on the resource class. * * This is similar in concept to form variable binding in web frameworks like * struts and MVC. * * @author brad */ public class BeanPropertySource implements PropertySource { private static final Logger log = LoggerFactory.getLogger(BeanPropertySource.class); private static final Object[] NOARGS = new Object[0]; public BeanPropertySource() { } @Override public Object getProperty(QName name, Resource r) throws NotAuthorizedException { PropertyDescriptor pd = getPropertyDescriptor(r, name.getLocalPart()); if (pd == null) { throw new IllegalArgumentException("no prop: " + name.getLocalPart() + " on " + r.getClass()); } try { return pd.getReadMethod().invoke(r, NOARGS); } catch (Exception ex) { if (ex.getCause() instanceof NotAuthorizedException) { NotAuthorizedException na = (NotAuthorizedException) ex.getCause(); throw na; } else { throw new RuntimeException(name.toString(), ex); } } } @Override public void setProperty(QName name, Object value, Resource r) throws NotAuthorizedException, PropertySetException { log.debug("setProperty: " + name + " = " + value); PropertyDescriptor pd = getPropertyDescriptor(r, name.getLocalPart()); try { pd.getWriteMethod().invoke(r, value); } catch (PropertySetException e) { throw e; } catch (Exception ex) { if (ex.getCause() instanceof NotAuthorizedException) { NotAuthorizedException na = (NotAuthorizedException) ex.getCause(); throw na; } else if (ex.getCause() instanceof PropertySetException) { PropertySetException na = (PropertySetException) ex.getCause(); throw na; } else { if (value == null) { log.error("Exception setting property: " + name.toString() + " to null"); } else { log.error("Exception setting property: " + name.toString() + " to value: " + value + " class:" + value.getClass()); } throw new RuntimeException(name.toString(), ex); } } } @Override public PropertyMetaData getPropertyMetaData(QName name, Resource r) { log.debug("getPropertyMetaData"); BeanPropertyResource anno = getAnnotation(r); if (anno == null) { log.debug(" no annotation: ", r.getClass().getCanonicalName()); return PropertyMetaData.UNKNOWN; } if (!name.getNamespaceURI().equals(anno.value())) { log.debug("different namespace", anno.value(), name.getNamespaceURI()); return PropertyMetaData.UNKNOWN; } PropertyDescriptor pd = getPropertyDescriptor(r, name.getLocalPart()); if (pd == null || pd.getReadMethod() == null) { LogUtils.debug(log, "getPropertyMetaData: no read method:", name.getLocalPart(), r.getClass()); return PropertyMetaData.UNKNOWN; } else { BeanProperty propAnno = pd.getReadMethod().getAnnotation(BeanProperty.class); if (propAnno != null) { if (!propAnno.value()) { log.trace( "getPropertyMetaData: property is annotated and value is false, so do not allow access"); return PropertyMetaData.UNKNOWN; } else { log.trace("getPropertyMetaData: property is annotated and value is true, so allow access"); } } else { if (anno.enableByDefault()) { log.trace( "getPropertyMetaData: no property annotation, property annotation is enable by default so allow access"); } else { log.trace( "getPropertyMetaData:no property annotation, class annotation says disable by default, decline access"); return PropertyMetaData.UNKNOWN; } } if (log.isDebugEnabled()) { log.debug("writable: " + anno.writable() + " - " + (pd.getWriteMethod() != null)); } boolean writable = anno.writable() && (pd.getWriteMethod() != null); if (writable) { return new PropertyMetaData(PropertyAccessibility.WRITABLE, pd.getPropertyType()); } else { return new PropertyMetaData(PropertyAccessibility.READ_ONLY, pd.getPropertyType()); } } } @Override public void clearProperty(QName name, Resource r) throws NotAuthorizedException { setProperty(name, null, r); } @Override public List<QName> getAllPropertyNames(Resource r) { BeanPropertyResource anno = getAnnotation(r); if (anno == null) { return null; } PropertyDescriptor[] pds = PropertyUtils.getPropertyDescriptors(r); List<QName> list = new ArrayList<QName>(); for (PropertyDescriptor pd : pds) { if (pd.getReadMethod() != null) { list.add(new QName(anno.value(), pd.getName())); } } return list; } public BeanPropertyResource getAnnotation(Resource r) { return r.getClass().getAnnotation(BeanPropertyResource.class); } public PropertyDescriptor getPropertyDescriptor(Resource r, String name) { try { PropertyDescriptor pd = PropertyUtils.getPropertyDescriptor(r, name); return pd; } catch (IllegalAccessException ex) { throw new RuntimeException(ex); } catch (InvocationTargetException ex) { throw new RuntimeException(ex); } catch (NoSuchMethodException ex) { return null; } } }