J2ME Learning Notes (II.)

This is a very, very simple example of writing a classmate, because I don't have a mobile device on hand, and I don't use any simulators at that time. , so the success of debugging at this level is out of control. The database is SQL Anywhere, and it feels good. Because it has not been studied before, so I think this thing convenient. I will not buy the melon again how to use SQL anywhere in detail, I also under its Chinese document to study. If the guy wants to be lazy and don't want to find his own, add my sans_reason@hotmail.com I sent you. Oh


/*
* If deployed to WINDOWSCE devices, copy Jul9.dll and Jul9_zh.jar themselves.
* Equipment should be installed Djeode
* Establish Test.lnk
*18# "\ Memory card \insignia Solutions Jeoderuntime\evm.exe"
*-djeode.evm.console.local.keep=true
*-djeode.evm.console.local.paging=true
*-djul.library.dir=\ultralite\lib
*-CP \ultralite\tutorial;\ultralite\lib\jul9_zh.jar
*customer
*/
/**
* @author liyou
*
*
*/
Import ianywhere.native_ultralite.*;
Import java.sql.SQLException;
public class customer{
Static Connection Conn;
public static void Main (String args[]) {
try{
Customer cust = new Customer ();
Cust.insert ();
Cust.select ();
Conn.close ();
}catch (SQLException e) {
E.printstacktrace ();
}
}
Public Customer () throws sqlexception{
Databasemanager dbmgr = new Databasemanager ();
/*
* Ultralite default database username and password ... How to change don't know, I won't this thing also did not study
*/
String parms = "UID=DBA"
+ ";p wd=sql"
+ "; File_name=f:\\j2me\\tutcustomer.udb"
+ "; SCHEMA_FILE=F:\\J2ME\\TUTCUSTOMER.USM"
+ "; Ce_file=\\ultralite\\tutorial\\tutcustomer.udb"
+ "; Ce_schema=\\ultralite\\tutorial\\tutcustomer.usm";
/*
* If you are deploying to a WINDOWSCE device, add two lines to this line
* CE_FILE=\\ULTRALITE\\TUTORIAL\\TUTCUSTOMER.UDB
* CE_SCHEMA=\\ULTRALITE\\TUTORIAL\\TUTCUSTOMER.USM
*
* In the desktop should be the system of these two lines have no effect drop! Watch yourself!
*/
try {
conn = Dbmgr.openconnection (parms);
System.out.println (
"Connect to Database tutcustomer!");
}catch (SQLException econn) {
if (Econn.geterrorcode () ==sqlcode.sqle_ultralite_database_not_found) {
To determine the SQL error code, if it does not have the database file, create it according to the drop pattern provided
conn = Dbmgr.createdatabase (parms);
SYSTEM.OUT.PRINTLN ("The database has been created based on the provided Ultralite schema");
}else{
Econn.printstacktrace ();
}
}
}
private void Insert () throws sqlexception{
Table t = conn.gettable ("Customer");
T.open ();
Short id = t.schema.getcolumnid ("id");
Short fname = T.schema.getcolumnid ("Fnamee");
Short lname = T.schema.getcolumnid ("Lnamee");
if (t.getrowcount () = = 0) {
To determine whether there is data inside the database, there is no longer add, no add ...
You don't tell me you don't know how to change this place.
T.insertbegin ();
T.setstring (fname, "Li");
T.setstring (lname, "you");
T.insert ();
Conn.commit ();
SYSTEM.OUT.PRINTLN ("Add data to the database!") " );
}else{
System.out.println ("There is already data in the database!") " );
}
T.close ();
}
private void Select () throws sqlexception{
Table t = conn.gettable ("Customer");
T.open ();
Short id = t.schema.getcolumnid ("id");
Short fname = T.schema.getcolumnid ("Fnamee");
Short lname = T.schema.getcolumnid ("Lnamee");
T.movebeforefirst ();
while (T.movenext ()) {
System.out.println (
"Id=" + t.getint (ID)
+ ", name =" + t.getstring (fname)
+ "" + t.getstring (lname)
+ "hahaha, success!" You boys come back to buy me dinner! Helped you do a lot of these things! ");
}
T.close ();
}
}