I am trying to configure tomcat7 on server with SSL because I need to send a request via https://

I am following steps -:

```
               1.Create a keystore file using Java
               2.Configure Tomcat to use the keystore

```

I tried to create a keystore directly with 

```
          keytool -genkey -alias tomcat -keyalg RSA

```

and then tried to access <https://[host]:8443> it worked

But when I tried to create keystore with the .cer file 

```
        keytool -import -trustcacerts -alias server -file your_site_name.p7b -keystore your_site_name.jks 

```

Also used 

```
         keytool -import -alias simple -file Example.cer -keystore exampleraystore

```

and tried to access <https://[host]:8443> it is not working .. showing "WEB PAGE CAN"T BE DISPLAYED"

why