/*
* 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 org.apache.commons.chain.config;
import org.apache.commons.digester.Digester;
import org.apache.commons.digester.RuleSetBase;
/**
* <p>Digester <code>RuleSet</code> for configuring <em>Chain of
* Responsibility</em> command chains, and adding them to an appropriate
* {@link org.apache.commons.chain.Catalog}. The following properties
* may be configured prior to executing the <code>addRuleInstance()</code>
* method in order to influence the rules that get added, with default
* values in square brackets:</p>
* <ul>
* <li><strong>catalogClass</strong> -- Fully qualified name of the
* implementation class used to create new
* {@link org.apache.commons.chain.Catalog} instances.
* If not specified, the default value is
* <code>org.apache.commons.chain.impl.CatalogBsae</code>.</li>
* <li><strong>catalogElement</strong> -- Name of the XML element representing
* the addition of a {@link org.apache.commons.chain.Catalog}.
* Any such catalog that is created will be registered with the
* {@link org.apache.commons.chain.CatalogFactory} instance for our
* application, under the name specified by the <code>nameAttribute</code>
* attribute (if present), or as the default {@link org.apache.commons.chain.Catalog}.
* If not specified, the default value is <code>catalog</code>.</li>
* <li><strong>chainClass</strong> -- Fully qualified name of the implementation
* class used to create new {@link org.apache.commons.chain.Chain} instances.
* If not specified, the default value is
* <code>org.apache.commons.chain.impl.ChainBase</code>.
* </li>
* <li><strong>chainElement</strong> -- Name of the XML element representing
* the addition of a {@link org.apache.commons.chain.Chain}. A chain
* element has the same functionality as a command element, except that
* it defaults the implementation class to
* <code>org.apache.commons.chain.impl.ChainBase</code>. [chain]</li>
* <li><strong>classAttribute</strong> -- Attribute on a chain (optional) or
* command (required) element that specifies the fully qualified class
* name of the implementation class that should be instantiated.
* [className]</li>
* <li><strong>commandElement</strong> -- Name of the XML element
* representing the addition of a {@link org.apache.commons.chain.Command}.
* An implementation class name must be provided on the attribute named by the
* <code>classAttribute</code> property. [command]</li>
* <li><strong>defineElement</strong> -- Name of the XML element
* that associates the element specified by the <code>nameAttribute</code>
* attributes with a {@link org.apache.commons.chain.Command} or
* {@link org.apache.commons.chain.Chain} implementation class
* named by the <code>classAttribute</code> attribute. [define]</li>
* <li><strong>nameAttribute</strong> -- Attribute on an outermost chain or
* command element that will be used to register this command with the
* associated {@link org.apache.commons.chain.Catalog} instance on the stack.
* [name]</li>
* <li><strong>namespaceURI</strong> -- The XML namespace URI with which these
* rules will be associated, or <code>null</code> for no namespace.
* [null]</li>
* </ul>
*
* @author Craig R. McClanahan
* @version $Revision: 480477 $ $Date: 2006-11-29 08:34:52 +0000 (Wed, 29 Nov 2006) $
*/
public class ConfigRuleSet extends RuleSetBase {
// ----------------------------------------------------- Instance Variables
private String catalogClass = "org.apache.commons.chain.impl.CatalogBase";
private String catalogElement = "catalog";
private String chainClass = "org.apache.commons.chain.impl.ChainBase";
private String chainElement = "chain";
private String classAttribute = "className";
private String commandElement = "command";
private String defineElement = "define";
private String nameAttribute = "name";
// ------------------------------------------------------------- Properties
/**
* <p>Return the fully qualified {@link org.apache.commons.chain.Catalog}
* implementation class.</p>
* @return The Catalog's class name.
*/
public String getCatalogClass() {
return (this.catalogClass);
}
/**
* <p>Set the fully qualified {@link org.apache.commons.chain.Catalog}
* implementation class.</p>
*
* @param catalogClass The new {@link org.apache.commons.chain.Catalog}
* implementation class
*/
public void setCatalogClass(String catalogClass) {
this.catalogClass = catalogClass;
}
/**
* <p>Return the element name of a catalog element.</p>
* @return The element name of a catalog element.
*/
public String getCatalogElement() {
return (this.catalogElement);
}
/**
* <p>Set the element name of a catalog element.</p>
*
* @param catalogElement The new element name
*/
public void setCatalogElement(String catalogElement) {
this.catalogElement = catalogElement;
}
/**
* <p>Return the fully qualified {@link org.apache.commons.chain.Chain}
* implementation class.</p>
* @return The Chain's class name.
*/
public String getChainClass() {
return (this.chainClass);
}
/**
* <p>Set the fully qualified {@link org.apache.commons.chain.Chain}
* implementation class.</p>
*
* @param chainClass The new {@link org.apache.commons.chain.Chain}
* implementation class
*/
public void setChainClass(String chainClass) {
this.chainClass = chainClass;
}
/**
* <p>Return the element name of a chain element.</p>
* @return The element name of a catalog element.
*/
public String getChainElement() {
return (this.chainElement);
}
/**
* <p>Set the element name of a chain element.</p>
*
* @param chainElement The new element name
*/
public void setChainElement(String chainElement) {
this.chainElement = chainElement;
}
/**
* <p>Return the attribute name of a class attribute.</p>
* @return The attribute name of a class attribute.
*/
public String getClassAttribute() {
return (this.classAttribute);
}
/**
* <p>Set the attribute name of a class attribute.</p>
*
* @param classAttribute The new attribute name
*/
public void setClassAttribute(String classAttribute) {
this.classAttribute = classAttribute;
}
/**
* <p>Return the element name of a command element.</p>
* @return The element name of a command element.
*/
public String getCommandElement() {
return (this.commandElement);
}
/**
* <p>Set the element name of a command element.</p>
*
* @param commandElement The new element name
*/
public void setCommandElement(String commandElement) {
this.commandElement = commandElement;
}
/**
* <p>Return the element name of a define element.</p>
* @return The element name of a define element.
*/
public String getDefineElement() {
return (this.defineElement);
}
/**
* <p>Set the element name of a define element.</p>
*
* @param defineElement The new element name
*/
public void setDefineElement(String defineElement) {
this.defineElement = defineElement;
}
/**
* <p>Return the attribute name of a name attribute.</p>
* @return The attribute name of an attribute element.
*/
public String getNameAttribute() {
return (this.nameAttribute);
}
/**
* <p>Set the attribute name of a name attribute.</p>
*
* @param nameAttribute The new attribute name
*/
public void setNameAttribute(String nameAttribute) {
this.nameAttribute = nameAttribute;
}
// --------------------------------------------------------- Public Methods
/**
* <p>Add the set of Rule instances defined in this RuleSet to the
* specified <code>Digester</code> instance, associating them with
* our namespace URI (if any). This method should only be called
* by a Digester instance.</p>
*
* @param digester Digester instance to which the new Rule instances
* should be added.
*/
public void addRuleInstances(Digester digester) {
// Add rules for a catalog element
digester.addRule("*/" + getCatalogElement(),
new ConfigCatalogRule(nameAttribute, catalogClass));
digester.addSetProperties("*/" + getCatalogElement());
// Add rules for a chain element
digester.addObjectCreate("*/" + getChainElement(),
getChainClass(),
getClassAttribute());
digester.addSetProperties("*/" + getChainElement());
digester.addRule("*/" + getChainElement(),
new ConfigRegisterRule(nameAttribute));
// Add rules for a command element
digester.addObjectCreate("*/" + getCommandElement(),
null,
getClassAttribute());
digester.addSetProperties("*/" + getCommandElement());
digester.addRule("*/" + getCommandElement(),
new ConfigRegisterRule(nameAttribute));
// Add rules for a define element
digester.addRule("*/" + getDefineElement(),
new ConfigDefineRule(getNameAttribute(),
getClassAttribute()));
}
}