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 org.apache.solr.core; import java.util.ArrayList; import java.util.Collections; import java.util.HashSet; import java.util.LinkedHashMap; import java.util.List; import java.util.Map; import org.apache.solr.common.MapSerializable; import org.apache.solr.common.util.NamedList; import org.apache.solr.common.util.Pair; import org.apache.solr.util.DOMUtil; import org.w3c.dom.Node; import org.w3c.dom.NodeList; import static java.util.Arrays.asList; import static java.util.Collections.unmodifiableList; import static java.util.Collections.unmodifiableMap; import static org.apache.solr.common.params.CoreAdminParams.NAME; import static org.apache.solr.schema.FieldType.CLASS_NAME; /** * An Object which represents a Plugin of any type * */ public class PluginInfo implements MapSerializable { public final String name, className, type, pkgName; public final NamedList initArgs; public final Map<String, String> attributes; public final List<PluginInfo> children; private boolean isFromSolrConfig; public PluginInfo(String type, Map<String, String> attrs, NamedList initArgs, List<PluginInfo> children) { this.type = type; this.name = attrs.get(NAME); Pair<String, String> parsed = parseClassName(attrs.get(CLASS_NAME)); this.className = parsed.second(); this.pkgName = parsed.first(); this.initArgs = initArgs; attributes = unmodifiableMap(attrs); this.children = children == null ? Collections.<PluginInfo>emptyList() : unmodifiableList(children); isFromSolrConfig = false; } /** class names can be prefixed with package name e.g: my_package:my.pkg.Class * This checks if it is a package name prefixed classname. * the return value has first = package name & second = class name */ static Pair<String, String> parseClassName(String name) { String pkgName = null; String className = name; if (name != null) { int colonIdx = name.indexOf(':'); if (colonIdx > -1) { pkgName = name.substring(0, colonIdx); className = name.substring(colonIdx + 1); } } return new Pair<>(pkgName, className); } public PluginInfo(Node node, String err, boolean requireName, boolean requireClass) { type = node.getNodeName(); name = DOMUtil.getAttr(node, NAME, requireName ? err : null); Pair<String, String> parsed = parseClassName(DOMUtil.getAttr(node, CLASS_NAME, requireClass ? err : null)); className = parsed.second(); pkgName = parsed.first(); initArgs = DOMUtil.childNodesToNamedList(node); attributes = unmodifiableMap(DOMUtil.toMap(node.getAttributes())); children = loadSubPlugins(node); isFromSolrConfig = true; } public PluginInfo(String type, Map<String, Object> map) { LinkedHashMap m = new LinkedHashMap<>(map); initArgs = new NamedList(); for (Map.Entry<String, Object> entry : map.entrySet()) { if (NAME.equals(entry.getKey()) || CLASS_NAME.equals(entry.getKey())) continue; Object value = entry.getValue(); if (value instanceof List) { List list = (List) value; if (!list.isEmpty() && list.get(0) instanceof Map) {//this is a subcomponent for (Object o : list) { if (o instanceof Map) o = new NamedList<>((Map) o); initArgs.add(entry.getKey(), o); } } else { initArgs.add(entry.getKey(), value); } } else { if (value instanceof Map) value = new NamedList((Map) value); initArgs.add(entry.getKey(), value); } } this.type = type; this.name = (String) m.get(NAME); Pair<String, String> parsed = parseClassName((String) m.get(CLASS_NAME)); this.className = parsed.second(); this.pkgName = parsed.first(); attributes = unmodifiableMap(m); this.children = Collections.<PluginInfo>emptyList(); isFromSolrConfig = true; } private List<PluginInfo> loadSubPlugins(Node node) { List<PluginInfo> children = new ArrayList<>(); //if there is another sub tag with a non namedlist tag that has to be another plugin NodeList nlst = node.getChildNodes(); for (int i = 0; i < nlst.getLength(); i++) { Node nd = nlst.item(i); if (nd.getNodeType() != Node.ELEMENT_NODE) continue; if (NL_TAGS.contains(nd.getNodeName())) continue; PluginInfo pluginInfo = new PluginInfo(nd, null, false, false); if (pluginInfo.isEnabled()) children.add(pluginInfo); } return children.isEmpty() ? Collections.<PluginInfo>emptyList() : unmodifiableList(children); } @Override public String toString() { StringBuilder sb = new StringBuilder("{"); if (type != null) sb.append("type = ").append(type).append(','); if (name != null) sb.append("name = ").append(name).append(','); if (className != null) sb.append("class = ").append(className).append(','); if (attributes != null && attributes.size() > 0) sb.append("attributes = ").append(attributes).append(','); if (initArgs != null && initArgs.size() > 0) sb.append("args = ").append(initArgs); sb.append("}"); return sb.toString(); } public boolean isEnabled() { String enable = attributes.get("enable"); return enable == null || Boolean.parseBoolean(enable); } public boolean isDefault() { return Boolean.parseBoolean(attributes.get("default")); } public PluginInfo getChild(String type) { List<PluginInfo> l = getChildren(type); return l.isEmpty() ? null : l.get(0); } public Map<String, Object> toMap(Map<String, Object> map) { map.putAll(attributes); Map m = map; if (initArgs != null) m.putAll(initArgs.asMap(3)); if (children != null) { for (PluginInfo child : children) { Object old = m.get(child.name); if (old == null) { m.put(child.name, child.toMap(new LinkedHashMap<>())); } else if (old instanceof List) { List list = (List) old; list.add(child.toMap(new LinkedHashMap<>())); } else { ArrayList l = new ArrayList(); l.add(old); l.add(child.toMap(new LinkedHashMap<>())); m.put(child.name, l); } } } return m; } /**Filter children by type * @param type The type name. must not be null * @return The mathcing children */ public List<PluginInfo> getChildren(String type) { if (children.isEmpty()) return children; List<PluginInfo> result = new ArrayList<>(); for (PluginInfo child : children) if (type.equals(child.type)) result.add(child); return result; } public static final PluginInfo EMPTY_INFO = new PluginInfo("", Collections.<String, String>emptyMap(), new NamedList(), Collections.<PluginInfo>emptyList()); private static final HashSet<String> NL_TAGS = new HashSet<>( asList("lst", "arr", "bool", "str", "int", "long", "float", "double")); public static final String DEFAULTS = "defaults"; public static final String APPENDS = "appends"; public static final String INVARIANTS = "invariants"; public boolean isFromSolrConfig() { return isFromSolrConfig; } public PluginInfo copy() { PluginInfo result = new PluginInfo(type, attributes, initArgs != null ? initArgs.clone() : null, children); result.isFromSolrConfig = isFromSolrConfig; return result; } }