This is my understanding of the OTA : - JAD is required. - JAD contains the URL that points to the JAR file in the MIDlet-Jar-URL attribute..(This is where the phone finds the JAR)
Now, I was reading the MIDP 2.0 spec (JSR 118) and something is bothering me .. i just might be understanding it incorrectly.
on Page 13 (PDF) , Chapter 2 OTA , Section MIDlet Suite Discovery 2nd Paragraph "Using the DA, the user SHOULD be able to access a network location and see a description of the MIDlet suite along with a link that, when selected , initiates the installation of the MIDlet suite. If the link refers to a JAR file as described in the MIDP specification, the JAR and its URL are passed back to the AMS on the device to start the installation process. ....."
My question :
Is it possible to implement the download of a MIDlet suite by only giving the jar and not the JAD .. isnt the MIDlet size also checked in the JAD to determine if there is enough memory on the device ??? and some other stuff...
I will try it out at work tommorrow ... I am sure I am understanding the wording of this paragraph incorrectly...
Any one has any comments ???
Everything that can go wrong will go wrong -Murphy
JAD is not necessary, but recommended for the following reasons.
1. If you install jut the JAR file, then the app will be treated as 'untrusted' (read security in J2ME for more details). 2. The minimum requirement to make an app 'trusted' is to have a JAD file. A trusted app, much like a trusted applet, has more access. 3. As you mentioned, you can also mention more parameters in the JAD file that would help the device be better prepared for the app.
I have a Sony T610 and I always send only the JAR file (can't even seem to get the JAD file installed!)