Java tutorial
/* * Copyright 2019 ThoughtWorks, Inc. * * 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.thoughtworks.go.util; import java.util.ArrayList; import java.util.List; import com.thoughtworks.go.config.AttributeAwareConfigTag; import com.thoughtworks.go.config.ConfigAttribute; import com.thoughtworks.go.config.ConfigTag; import com.thoughtworks.go.config.registry.ConfigElementImplementationRegistry; import com.thoughtworks.go.domain.Task; import org.apache.commons.lang3.ObjectUtils; import org.jdom2.Attribute; import org.jdom2.Element; import org.jdom2.Namespace; import org.jdom2.output.XMLOutputter; import static com.thoughtworks.go.util.ExceptionUtils.bomb; public class ConfigUtil { private final String configFile; public ConfigUtil(String configFile) { this.configFile = (String) ObjectUtils.defaultIfNull(configFile, "<no config file specified>"); } public static List<String> allTasks(ConfigElementImplementationRegistry registry) { List<String> allTasks = new ArrayList<>(); for (Class<? extends Task> task : registry.implementersOf(Task.class)) { AttributeAwareConfigTag attributeAwareConfigTag = task.getAnnotation(AttributeAwareConfigTag.class); if (attributeAwareConfigTag != null && !allTasks.contains(attributeAwareConfigTag.value())) { allTasks.add(attributeAwareConfigTag.value()); } ConfigTag tag = task.getAnnotation(ConfigTag.class); if (tag != null && !allTasks.contains(tag.value())) { allTasks.add(tag.value()); } } return allTasks; } public Element getChild(Element e, ConfigTag tag) { Element child = child(e, tag); if (child == null) { throw bomb("Error finding child '" + tag + "' in config: " + configFile + elementOutput(e)); } return child; } private Element child(Element e, ConfigTag tag) { return e.getChild(tag.value(), Namespace.getNamespace(tag.namespacePrefix(), tag.namespaceURI())); } public String getAttribute(Element e, String attribute) { Attribute attr = e.getAttribute(attribute); if (attr == null) { throw bomb("Error finding attribute '" + attribute + "' in config: " + configFile + elementOutput(e)); } return attr.getValue(); } public String elementOutput(Element e) { return "\n\t" + new XMLOutputter().outputString(e); } public boolean hasChild(Element e, ConfigTag tag) { return child(e, tag) != null; } public String getAttribute(Element e, String attribute, String defaultValue) { if (!hasAttribute(e, attribute)) { return defaultValue; } return getAttribute(e, attribute); } public boolean hasAttribute(Element e, String attribute) { return e.getAttribute(attribute) != null; } public boolean atTag(Element e, String tag) { return e.getName().equals(tag); } public boolean optionalAndMissingAttribute(Element e, ConfigAttribute attribute) { boolean optional = attribute.optional(); boolean isMissingAttribute = !hasAttribute(e, attribute.value()); if (!optional && isMissingAttribute) { throw bomb("Non optional attribute '" + attribute.value() + "' is not in element: " + elementOutput(e)); } return optional && isMissingAttribute; } public Object getAttribute(Element e, ConfigAttribute attribute) { if (optionalAndMissingAttribute(e, attribute)) { return null; } return getAttribute(e, attribute.value()); } public boolean optionalAndMissingTag(Element e, ConfigTag tag, boolean optional) { boolean isMissingElement = !hasChild(e, tag); if (!optional && isMissingElement) { throw bomb("Non optional tag '" + tag + "' is not in config file. Found: " + elementOutput(e)); } return optional && isMissingElement; } }