Learning notes for j2-based learning (1)

First of all, I declare that I am really a layman for J2's, and because work has nothing to do with it, there will certainly be a lot of experts
They look very mentally retarded. Oh, I hope you don't want bs. At the same time, I hope you can give me some advice. Haha.
If you are interested, look at the content of J2's. In fact, it is mainly to help a brother complete his graduation design. Haha, I don't know him every day
There is something busy with US. I only know that when I ask him, he will tell me that he is going to work .. Forget it. Wait for him to come back.
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At present, I have read this article for three days. On the first day, I read some basic concepts of j2s. Alas, these things have never been touched
There is no way, there is no basic concept, there is no way. The next day, I helped him write a database operation program running on the PDA. Of course, 10
Points are simple. On the third day, things suddenly changed, requiring more and more things. Or, your own interests have also come up.
Let's take a look.
Today, I will put some key things that I saw on the first day. I will take the time to write it to that kid tomorrow.
Put the program on the PDA. In the future, I will take out some of my learning processes, thoughts, and difficulties, and work with you.
Share.
Well, first of all, it must be the most important and simplest concept? Not a good description.
Expression, J2EE> J2SE> J2SE> j2> smart card, which is also the java technology positioning provided by sun. Of course
Based on J2SE. (However, some basic types and basic objects are supported for different options .) Haha
This is the simplest.
Let's talk about the terms that make me very depressed at the beginning when I read the materials,
So the first time was hard. Take it out. If the old man wants to learn j2_^
1. CLDC: Connected Limited Device Configuration -- applicable to power Limited applications such as mobile phones and PDAs.
2. CDC: Connected Device Configuration -- applied to devices with sufficient power supply.
The box is within this range of ^_^
3. For different class library support, the class libraries supported by the j2-cldc are included in the class libraries of the j2-cdc. Compared with J2SE,
Their supported class libraries are reduced and expanded. Because of the differences between CLDC and CDC, java introduces the concept of Configuration.
. Well, I think Configuration can be used as the specifications of the two embedded devices for J2's. The main difference between J2SE and J2SE
Java. microedition. io class library is introduced in addition to some basic library support.
4. Profile: Profile is the specification of the architecture above Configuration, and its existence should be in order to distinguish
Embedded in the system, how should java be developed and what functions should they have. It depends on how to display the interfaces used by various embedded systems.
In Profile.