Forum Moderators: phranque
Tomcat is a Java Servlet container; it can run 'in-process' or 'out of process'. If it's running 'in process', then you can think of it as an add-on (one of the more complex ones); if it's running out-of-process, Tomcat is its own server. One of the primary advantages of in-process is performance; there's less overhead since Apache passes control to Tomcat over JNI instead of using, for instance, some sort of TCP-based protocol. One of the primary advantages to running out-of-process is that it allows you to decouple your Java application(s) from your webserver; indeed, one could set up a farm of Apache webservers in front of a farm of Tomcat servers, and have the former load-balance across the latter; the two farms could even be in two different places, geographically (although that's generally not a good idea, since the farther the two farms are from one another, the slower the overall responsetime is likely to be).
So if you were running it "out of process" in order to load balance your servlets, and were wanting to use jsp as a link between the browser/user you would run it in process with a normal server on port 80 to allow access to your jsps which would then talk to the other "out of process" servers on port 8080?
On the other hand, if running Tomcat in-process, you'd use the JNI worker, which knows how to forward requests to an in-process instance. You don't need to run an in-process instance to get to an out-of-process instance.
More info on Tomcat is available at [jakarta.apache.org ]; I pulled some of this information from [jakarta.apache.org ].
Does that answer your question, or did I misunderstand? =)
Next, can't we run .jsp plus .php on port 80 using Apache HTTP/Tomcat Servers. Suppose a Web site is using both PHP and Java technologies, then?
What's relation b/w Catalina -n- Tomcat?
Why Tomcat runs at command prompt? Can't it run as Windows service like Apache do ( I'm using Windows 2003 )? Why there is no SAPI module for .jsp as we've for .php
I'm very curious! Don't mind, please.
Next, can't we run .jsp plus .php on port 80 using Apache HTTP/Tomcat Servers. Suppose a Web site is using both PHP and Java technologies, then?
If want to use both technologies, I'd recommend running Apache + PHP with the proper Tomcat worker, and then run Tomcat. As discussed above, you could run Tomcat either in-process or out-of process. Another possibility would be to run one 'light' Apache instance which serves up static content and then uses mod_proxy to send PHP requests to a second PHP-enabled Apache instance and jsp requests to to a *third* Apache instance that is Tomcat-enabled. Possibilities a go-go; the trick is to figure out what you have the money for (hardware-wise) and benchmark (heh. there's that word again.) to determine which configuration gives you maximum performance.
What's relation b/w Catalina -n- Tomcat?
Someone check me on this: Tomcat is the name of the application; Catalina is the name of the Servlet container within Tomcat.
Why Tomcat runs at command prompt? Can't it run as Windows service like Apache do ( I'm using Windows 2003 )?
Can't help you there; I get paid to NOT run windows machines. =)
Why there is no SAPI module for .jsp as we've for .php
I'm not sure I understand what you're asking here. If you're asking "why isn't there an Apache module for running .jsp files since there's a PHP module for running PHP files?", I couldn't give you a solid answer. I do know that while the PHP module can be over 1M in size when compiled, Tomcat is MUCH larger; Tomcat is a webserver / servlet container written *in* java. I'm sure you could write a module to do that if you wanted to (although I imagine the amount of memory Apache would need would be obscene, just for starters), but splitting it off into a seperate process gives you more flexibility. I'm not sure what (if any) gains would be achieved by having mod_java.so, or some such. I leave decisions like this up to the Tomcat developers, who know FAR more about applicatooin architecture than I do. =)
