Tomcat下webapps访问认证BASIC Authentication设置

今天主要练习了tomcat下访问认证的设置，也更深入一点的了解了tomcat-user.xml

首先在$CATALINA_HOME/conf/tomcat-users.xml中添加用来登陆指定webapps的用户，如下

<tomcat-users>
    <role rolename="tomcat"/>
    <role rolename="manager"/>
    <user username="tomcat" password="tomcat" roles="tomcat"/>
    <user username="manager" password="manager" roles="manager"/>
</tomcat-users>

之后在需要添加登陆认证的webapps下修改其web.xml文件，这里以tomcat自带的examples为例，修改$CATALINA_HOME/webapps/examples/WEB-INF/web.xml，添加（修改）security-constraint字段，如下

<security-constraint>
  <display-name>Example Security Constraint</display-name>
  <web-resource-collection>
     <web-resource-name>Protected Area</web-resource-name>
     <url-pattern>/*</url-pattern>
     <http-method>DELETE</http-method>
     <http-method>GET</http-method>
     <http-method>POST<