/*
* Copyright 2007-2009 the original author or authors.
*
* 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 net.paoding.rose.web.impl.mapping;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import net.paoding.rose.util.PrinteHelper;
import net.paoding.rose.web.annotation.ReqMethod;
import net.paoding.rose.web.impl.module.ControllerRef;
import net.paoding.rose.web.impl.module.MethodRef;
import net.paoding.rose.web.impl.module.Module;
import net.paoding.rose.web.impl.thread.ActionEngine;
import net.paoding.rose.web.impl.thread.ControllerEngine;
import net.paoding.rose.web.impl.thread.Engine;
import net.paoding.rose.web.impl.thread.LinkedEngine;
import net.paoding.rose.web.impl.thread.ModuleEngine;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
*
* @author 王志亮 [qieqie.wang@gmail.com]
*
*/
public class TreeBuilder {
protected static final Log logger = LogFactory.getLog(TreeBuilder.class);
/*
* 构造一个树，树的结点是地址-资源映射，每个结点都能回答是否匹配一个字符串，每个匹配的节点都知道如何执行对该资源的操作.
* 构造树的过程：
* 识别组件==>求得他的资源定义==>判断是否已经创建了==>未创建的创建一个树结点==>已创建的找出这个结点
* ==>在这个资源增加相应的操作以及逻辑==>若是新建的结点把它加到树中，同时满足遍历、匹配顺序要求
*/
public void create(MappingNode tree, List<Module> modules) {
addRoot(tree, modules);
check(tree, tree, "");
}
private void addRoot(MappingNode rootNode, List<Module> modules) {
for (Module module : modules) {
addModule(rootNode, module);
}
}
private void addModule(final MappingNode rootNode, Module module) {
List<Mapping> terms = MappingFactory.parse(module.getMappingPath());
LinkedEngine rootEngine = rootNode.getMiddleEngines().getEngines(ReqMethod.GET)[0];
MappingNode parent = rootNode;
for (Mapping mapping : terms) {
if (mapping.getDefinition().length() == 0) {
continue;
}
MappingNode temp = parent.getChild(mapping.getDefinition());
if (temp == null) {
temp = new MappingNode(mapping);
parent.linkAsChild(temp);
}
parent = temp;
}
LinkedEngine moduleEngine = new LinkedEngine(rootEngine, new ModuleEngine(module), parent);
parent.getMiddleEngines().addEngine(ReqMethod.ALL, moduleEngine);
// controllers
List<ControllerRef> controllers = module.getControllers();
for (ControllerRef controller : controllers) {
addController(module, parent, moduleEngine, controller);
}
}
private void addController(Module module, MappingNode moduleNode, LinkedEngine moduleEngine,
ControllerRef controller) {
//
Engine engine = new ControllerEngine(module, controller);
Set<String> mappingPaths = new HashSet<String>(Arrays.asList(controller.getMappingPaths()));
for (String mappingPath : mappingPaths) {
List<Mapping> mappings = MappingFactory.parse(mappingPath);
//
MappingNode target = moduleNode;
for (Mapping mapping : mappings) {
if (mapping.getDefinition().length() == 0) {
continue;
}
MappingNode temp = target.getChild(mapping.getDefinition());
if (temp == null) {
temp = new MappingNode(mapping);
target.linkAsChild(temp);
}
target = temp;
}
LinkedEngine controllerEngine = new LinkedEngine(moduleEngine, engine, target);
target.getMiddleEngines().addEngine(ReqMethod.ALL, controllerEngine);
//
// actions
MethodRef[] actions = controller.getActions();
for (MethodRef action : actions) {
addAction(module, controller, action, target, controllerEngine);
}
}
}
private void addAction(Module module, ControllerRef controller, MethodRef action,
MappingNode controllerNode, LinkedEngine controllerEngine) {
Map<String, Set<ReqMethod>> mappingPaths = action.getMappings();
if (mappingPaths.size() == 0) {
return;
}
Engine actionEngine = new ActionEngine(module, controller.getControllerClass(),//
controller.getControllerObject(), action.getMethod());
for (String mappingPath : mappingPaths.keySet()) {
List<Mapping> mappings = MappingFactory.parse(mappingPath);
MappingNode target = controllerNode;
for (Mapping mapping : mappings) {
if (mapping.getDefinition().length() == 0) {
continue;
}
MappingNode temp = target.getChild(mapping.getDefinition());
if (temp == null) {
temp = new MappingNode(mapping);
target.linkAsChild(temp);
}
target = temp;
}
//
for (ReqMethod method : mappingPaths.get(mappingPath)) {
LinkedEngine linkedActionEngine = new LinkedEngine(//
controllerEngine, actionEngine, target);
target.getLeafEngines().addEngine(method, linkedActionEngine);
}
}
}
/**
* 检查整个树的状况，尽可能报告可能存在的问题
*
* @param tree
* @param parent
* @param prefix
*/
private void check(MappingNode tree, MappingNode parent, String prefix) {
MappingNode child = parent.getLeftMostChild();
MappingNode sibling = null;
while (child != null) {
if (sibling != null) {
if (child.compareTo(sibling) == 0) {
logger.error("mapping conflicts: '" + child.getMapping().getDefinition()
+ "' conflicts with '" + sibling.getMapping().getDefinition()
+ "' in '" + prefix + "'; here is the mapping tree, "
+ "you can find the conflict in it:\n" + PrinteHelper.list(tree));
throw new IllegalArgumentException("mapping conflicts: '"
+ child.getMapping().getDefinition() + "' conflicts with '"
+ sibling.getMapping().getDefinition() + "' in '" + prefix + "'");
}
}
check(tree, child, prefix + child.getMapping().getDefinition());
sibling = child;
child = child.getSibling();
}
}
}