建立文件夹
/home/tomcat/tomcat-9.0.34/cert

keytool -genkey -alias Piccsug -keyalg RSA -storetype PKCS12 -keysize 2048 -sigalg SHA256withRSA -dname "CN=`hostname`,OU=Picclife,O=tomcat,L=beijing,S=beijing,C=China" -keypass PiccSug#2021 -keystore tomcat.jks -storepass PiccSug#2021 -validity 3650

server.xml中修改以下两个地方：
<Connector port="8081" protocol="HTTP/1.1"
               connectionTimeout="20000"
               redirectPort="4430" />

复制原有的被注释掉配置，改成以下配置
<Connector port="4430"  protocol="org.apache.coyote.http11.Http11NioProtocol"
                maxThreads="150"  SSLEnabled="true">
    <SSLHostConfig>
        <Certificate certificateKeystoreFile="/home/tomcat/tomcat-9.0.34/cert/tomcat.jks"
                         type="RSA" certificateKeystorePassword="PiccSug#2021" />
    </SSLHostConfig>
</Connector>

应用web.xml中加入，以tomcat自带的项目examples为例
<security-constraint>
  <web-resource-collection >
     <web-resource-name >SSL</web-resource-name>
         <url-pattern>/*</url-pattern>
  </web-resource-collection>
  <user-data-constraint>
    <transport-guarantee>CONFIDENTIAL</transport-guarantee>
  </user-data-constraint>
</security-constraint>

访问：http://192.168.129.138:8081/examples/
跳转：https://192.168.129.138:4430/examples/

或者直接访问：https://192.168.129.138:4430/examples/

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