解决方案：
Java Keytool生成数字证书：
keytool -genkey -alias webmin.com -keyalg RSA
 -keystore /home/demo/webminkey -validity 365
其 中，RSA-非对称加密；-validity 365：证书有效期为365天，keytool默认生成的有效期为90天。

Jetty服务器配置config.xml:<?xml version="1.0" encoding="UTF-8"?>
< MetaData  xmlns ="http://www.osgi.org/xmlns/metatype/v1.0.0" >
     < OCD  name ="%configurationName"  id ="server.config"  description ="%configurationDescription" >
         < AD  id ="http.enabled"  type ="Boolean"  default ="true" />
         < AD  id ="http.port"  type ="Integer"  default ="0" />
         < AD  id ="http.host"  type ="String"  cardinality ="1" />
         < AD  id ="https.enabled"  type ="Boolean"  default ="false" />
         < AD  id ="https.port"  type ="Integer"  default ="0" />
         < AD  id ="https.host"  type ="String"  cardinality ="1" />
         < AD  id ="ssl.keystore"  type ="String"  cardinality ="1" />
         < AD  id ="ssl.password"  type ="String"  cardinality ="1" />
         < AD  id ="ssl.keypassword"  type ="String"  cardinality ="1" />
         < AD  id ="ssl.needclientauth"  type ="Boolean"  cardinality ="1" />
         < AD  id ="ssl.wantclientauth"  type ="Boolean"  cardinality ="1" />
         < AD  id ="ssl.protocol"  type ="String"  cardinality ="1" />
         < AD  id ="ssl.algorithm"  type ="String"  cardinality ="1" />
         < AD  id ="ssl.keystoretype"  type ="String"  cardinality ="1" />
         < AD  id ="context.path"  type ="String"  cardinality ="1" />
         < AD  id ="context.sessioninactiveinterval"  type ="Integer"  cardinality ="1" />
         < AD  id ="other.info"  type ="String"  cardinality ="1" />
     </ OCD >
     < Designate  pid ="org.eclipse.equinox.http.jetty.config.designate"  factoryPid ="org.eclipse.equinox.http.jetty.config"  bundle ="*" >
         < Object  ocdref ="server.config" />
     </ Designate >
</ MetaData >

在java配置文件configuration/config.ini中添加参数：

# enable ssl
org.eclipse.equinox.http.jetty.https.enabled=true
org.eclipse.equinox.http.jetty.http.enabled=false
org.eclipse.equinox.http.jetty.ssl.keystore=webminkey
org.eclipse.equinox.http.jetty.ssl.password=administrator
org.eclipse.equinox.http.jetty.ssl.keypassword=webmin

# set ssl port (defaults to 443)
org.eclipse.equinox.http.jetty.https.port=443
#org.eclipse.equinox.http.jetty.http.port=8088



测试：
浏览器中输入url： https://localhost/