介绍：
默认情况下我们会在tomcat中部署项目，一般情况我们会用eclipse 直接部署到tomcat进行调试，但是在正式的开发环境中会有很多不方便时候，项目有没有启动或者有没有假死的情况，更本不能判断到底项目有没有启动，那么我们就开配置一下tomcat用户名和密码，这样就可以登录tomcat后台，查看当前项目是否启动，并且可以管理启动和停止等等的操作功能
作用：
1、管理项目启动停止
2、动态部署项目
3、查看tomcat内存情况 等等功能
一、下载tomcat地址，自行选择一个版本，本次演示采用tomcat8
http://mirror.bit.edu.cn/apache/tomcat/
二、查看目录，找到tomcat/conf/tomcat-users.xml
三、打开配置文件，将以下内容文件复制到tomcat-users标签，其中用户名[admin]和密码[123456]，然后再启动tomcat
<role rolename="manager-gui"/>
<role rolename="admin-gui"/>
<user username="admin" password="123456" roles="manager-gui,admin-gui"/>完整配置
<?xml version="1.0" encoding="UTF-8"?>
<!--
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.
--><tomcat-users version="1.0" xmlns="http://tomcat.apache.org/xml" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://tomcat.apache.org/xml tomcat-users.xsd">
<!--
NOTE: By default, no user is included in the "manager-gui" role required
to operate the "/manager/html" web application. If you wish to use this app,
you must define such a user - the username and password are arbitrary. It is
strongly recommended that you do NOT use one of the users in the commented out
section below since they are intended for use with the examples web
application.
-->
<!--
NOTE: The sample user and role entries below are intended for use with the
examples web application. They are wrapped in a comment and thus are ignored
when reading this file. If you wish to configure these users for use with the
examples web application, do not forget to remove the <!.. ..> that surrounds
them. You will also need to set the passwords to something appropriate.
-->
<!--
<role rolename="tomcat"/>
<role rolename="role1"/>
<user username="tomcat" password="<must-be-changed>" roles="tomcat"/>
<user username="both" password="<must-be-changed>" roles="tomcat,role1"/>
<user username="role1" password="<must-be-changed>" roles="role1"/>
-->
<role rolename="manager-gui"/>
<role rolename="admin-gui"/>
<user username="admin" password="123456" roles="manager-gui,admin-gui"/>
</tomcat-users>
四、访问tomcat ,点击manager App 按钮进入项目管理，查看当前tomcat下有哪些项目存在，点击start启动，stop停止，还可以上传部署项目
