/*
* Copyright 2010 Alibaba Group Holding Limited.
* All rights reserved.
*
* Licensed 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 com.alibaba.antx.config.descriptor;
import com.alibaba.antx.config.ConfigException;
import com.alibaba.antx.config.ConfigResource;
import org.apache.commons.digester.Digester;
import org.apache.commons.digester.plugins.PluginCreateRule;
import org.apache.commons.digester.plugins.PluginDeclarationRule;
import org.apache.commons.digester.plugins.PluginRules;
import java.io.IOException;
import java.io.InputStream;
import java.util.HashMap;
import java.util.Map;
/**
* װ��һ��config descriptor�Ĺ����ࡣ
*
* @author Michael Zhou
*/
public class ConfigDescriptorLoader {
/**
* ��ָ��������װ�������ļ���
*
* @param url �����ļ���URL
* @param name descriptor�����֣�·����
* @return config descriptor
*/
public synchronized ConfigDescriptor load(ConfigResource descriptorResource, InputStream istream) {
Digester digester = getDigester();
digester.push(new ConfigDescriptor(descriptorResource));
try {
return (ConfigDescriptor) digester.parse(istream);
} catch (Exception e) {
throw new ConfigException("Failed to load config descriptor: " + descriptorResource.getURL(), e);
}
}
/**
* ȡ��validator���б�
*/
public synchronized Map loadValidatorClasses() {
Digester digester = loadValidatorPlugins();
return (Map) digester.pop();
}
/**
* ������ȡdescriptor��digester��
*/
protected Digester getDigester() {
Digester digester = loadValidatorPlugins();
// config
digester.addSetProperties("config");
// config/group
digester.addObjectCreate("config/group", ConfigGroup.class);
digester.addSetProperties("config/group");
digester.addSetNext("config/group", "addGroup");
// config/group/property
digester.addObjectCreate("config/group/property", ConfigProperty.class);
digester.addSetProperties("config/group/property");
digester.addCallMethod("config/group/property", "afterPropertiesSet");
digester.addSetNext("config/group/property", "addProperty");
// config/group/property/validator
PluginCreateRule pcr = new PluginCreateRule(ConfigValidator.class);
pcr.setPluginIdAttribute(null, "name");
digester.addRule("config/group/property/validator", pcr);
digester.addSetNext("config/group/property/validator", "addValidator");
// config/script/generate
digester.addObjectCreate("config/script/generate", ConfigGenerate.class);
digester.addSetProperties("config/script/generate");
digester.addSetNext("config/script/generate", "addGenerate");
digester.clear();
return digester;
}
/**
* ��ȡvalidators.xml�е�validator���塣
*/
private Digester loadValidatorPlugins() {
Digester digester = new Digester();
digester.setRules(new PluginRules());
digester.addObjectCreate("config-property-validators", HashMap.class);
digester.addCallMethod("config-property-validators/validator", "put", 2);
digester.addCallParam("config-property-validators/validator", 0, "id");
digester.addCallParam("config-property-validators/validator", 1, "class");
digester.addRule("config-property-validators/validator", new PluginDeclarationRule());
InputStream istream = getClass().getResourceAsStream("validators.xml");
try {
digester.push(digester.parse(istream));
} catch (Exception e) {
throw new ConfigException("Failed to load validators", e);
} finally {
if (istream != null) {
try {
istream.close();
} catch (IOException e) {
}
}
}
digester.getRules().clear();
return digester;
}
}