对我来说算是挑战性的一个J2ME数据存储的问题,高手请进！

[老猫的TOM]

一直在做J2EE的开发，最近公司拉了一个J2ME手持机<PDA>（其实和手机差不多）开发项目，本人算是第一次做这样的项目，如果问题问的有些弱还希望高手不要见笑。
下面开始说问题：
PAD使用的是WTK平台，要实现的功能是：对数据进行保存、修改、删除、查询，由于环境的问题，程序要求在无网络的情况下能够正常运行，所以运行环境算是单机版的。
数据格式很简单包含：档案ID、卡号、用户名、金额。
数据量最少在一万条以上，由于只能存储在本机环境内，这对于手持机来说不是件容易的事情。起先准备使用操作本地文本文件的方式存储（txt文件，每一行为一条数据）但是j2me对文本文件的操作真是太低级。对于查询和修改数据不易操作，而且数据过大会导致内存溢出。
所以本人准备尝试使用嵌入式数据库来完成，目前选用的数据库位JMESQL,网上对于这个数据库的操作知识并不是很多，只能在官方找到所谓的例子，可是操作中创建表一直不成功。后台打印异常为：

开始创建表----
..............false
开始创建表----
br.com.dreamsource.mobile.jmesql.exceptions.SQLException: already exists: PRICETABLE -- S0001 in statement [CREATE TABLE priceTable (   id int identity,    name varchar(20) not null,    percent float not null,   primary key(id))] -- Table
	at br.com.dreamsource.mobile.jmesql.jdbcResultSet.<init>(+37)
	at br.com.dreamsource.mobile.jmesql.jdbcConnection.executeStandalone(+19)
	at br.com.dreamsource.mobile.jmesql.jdbcConnection.execute(+21)
	at br.com.dreamsource.mobile.jmesql.jdbcStatement.fetchResult(+36)
	at br.com.dreamsource.mobile.jmesql.jdbcStatement.execute(+5)
	at com.sqlplus.FrameMainMIDlet.createDatabase(+48)
	at com.sqlplus.FrameMainMIDlet.commandAction(+33)
	at javax.microedition.lcdui.Display$DisplayAccessor.commandAction(+282)
	at javax.microedition.lcdui.Display$DisplayManagerImpl.commandAction(+10)
	at com.sun.midp.lcdui.DefaultEventHandler.commandEvent(+68)
	at com.sun.midp.lcdui.AutomatedEventHandler.commandEvent(+47)
	at com.sun.midp.lcdui.DefaultEventHandler$QueuedEventHandler.handleVmEvent(+186)
	at com.sun.midp.lcdui.DefaultEventHandler$QueuedEventHandler.run(+57)

看字面意思是提示数据表已存在，但是我明明是第一次创建。
附上源码希望高手能帮忙看看：

package com.sqlplus;

import java.util.Vector;

import javax.microedition.lcdui.Command;
import javax.microedition.lcdui.CommandListener;
import javax.microedition.lcdui.Display;
import javax.microedition.lcdui.Displayable;
import javax.microedition.lcdui.Form;
import javax.microedition.lcdui.TextField;
import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;

import br.com.dreamsource.mobile.jmesql.jdbcConnection;
import br.com.dreamsource.mobile.jmesql.jdbcDriver;
import br.com.dreamsource.mobile.jmesql.jdbcPreparedStatement;
import br.com.dreamsource.mobile.jmesql.jdbcResultSet;
import br.com.dreamsource.mobile.jmesql.jdbcStatement;
import br.com.dreamsource.mobile.jmesql.exceptions.SQLException;


public class FrameMainMIDlet extends MIDlet implements CommandListener {

	private Form mainForm;
	

	private static DatabaseManager myDatabaseManager;
	private UserPOJO userPOJO;

	TextField tf = new TextField("要写入的数据", "", 100, TextField.ANY);

	TextField cx = new TextField("查询条件", "", 100, TextField.ANY);

	TextField cxjg = new TextField("查询结果", "", 100, TextField.ANY);

	Command a_cmdSet = new Command("添加", Command.SCREEN, 0);

	Command w_cmdSet = new Command("修改", Command.SCREEN, 0);

	Command r_cmdSet = new Command("查询", Command.SCREEN, 0);
	
	Command c_cmdSet = new Command("创建表", Command.SCREEN, 0);

	Command exitCommand = new Command("退出", Command.EXIT, 0);

	public FrameMainMIDlet() {

		mainForm = new Form("嵌入式数据库");
		mainForm.append(tf);
		mainForm.append(cx);
		mainForm.append(cxjg);
		mainForm.addCommand(exitCommand);
		mainForm.addCommand(c_cmdSet);
		mainForm.addCommand(r_cmdSet);
		mainForm.addCommand(w_cmdSet);
		mainForm.addCommand(a_cmdSet);
		mainForm.setCommandListener(this);

	}

/*	*//**
	 * 检查数据库如果没有开始创建
	 * 
	 * @return
	 * @throws Exception
	 */

      public  void createDatabase(UserPOJO userPOJO) {
	        jdbcDriver driver = new jdbcDriver();
	        
	      //  String userName = userPOJO.getUserName();
	       // String userPassword = userPOJO.getPasswd();
	        
	        userPOJO.setUserName("SA");
	        userPOJO.setPasswd("");
	        userPOJO.setDbName(Consts.DATABASE_NAME);
	        
	        jdbcConnection connection;
			try {
				connection = driver.connect(userPOJO.getAsProperties());
				  jdbcStatement statement = connection.createStatement();
			        boolean l=statement.execute(Consts.CREATE_PRICETABLE_TBL);
			        System.out.println(".............."+l);
			        if(l==true){
			        
			        	tf.setString("创建表成功.........");
			        	
			        	 boolean k=statement.execute("insert into priceTable values (null, 'tabela1', 10)");
			        	 if(k==true){
			        		 
			        		 cx.setString("插入数据成功.......");
			        		 
			        		 try {
			        			 
			        			   jdbcPreparedStatement prepared =connection.prepareStatement("select name from priceTable");
			        			   jdbcResultSet res = prepared.executeQuery();
			        				
			        				int i;
			        				StringBuffer Results = new StringBuffer();
			        				this.cxjg.setString("");
			        				System.out.println("数据查询"+Results);
			        				if (!(res == null)) {
			        					while (res.next()) {
			        						for (i = 1; i <= res.getColumnCount(); i++) {
			        							this.cxjg.setString(this.cxjg.getString()
			        									+ res.getColumnName(i) + " -- "
			        									+ res.getString(i) + "\n");
			        						}
			        						this.cxjg.setString(this.cxjg.getString());
			        					}
			        				}
			        			} catch (Exception e) {
			        				this.cxjg.setString(e.getMessage());
			        			}
			        	 }else{
			        		 
			        		 cx.setString("插入数据失败......."); 
			        		 
			        	 }
			        	
			        	
			        }else{
			        	
			        	tf.setString("创建表失败.....");
			        	
			        }
			       // boolean i=statement.execute(Consts.CREATE_CUSTOMER_TBL);
			       
			       
			} catch (SQLException e1) {
				// TODO 自动生成 catch 块
				e1.printStackTrace();
			}
	      
	    }

	protected void destroyApp(boolean arg0) throws MIDletStateChangeException {
		// TODO 自动生成方法存根

	}

	protected void pauseApp() {
		// TODO 自动生成方法存根

	}

	protected void startApp() throws MIDletStateChangeException {
		// TODO 自动生成方法存根
		
		
		
		    this.userPOJO = new UserPOJO();
	        this.userPOJO.setConnectionURL(Consts.DATABASE_CONNETION_STRING);
	        this.userPOJO.setDbName(Consts.DATABASE_NAME);
	        if (DatabaseManager.databaseExists(Consts.DATABASE_NAME)) {
	        	Display.getDisplay(this).setCurrent(mainForm);
	        } else {
	        	Display.getDisplay(this).setCurrent(mainForm);
	        }

	}

	public void commandAction(Command command, Displayable displayable) {
		if (command == r_cmdSet) {
			
			

			

		}else if(command==c_cmdSet){
			System.out.println("开始创建表----");
			try {
				createDatabase( userPOJO);
			} catch (Exception e) {
				// TODO 自动生成 catch 块
				e.printStackTrace();
			}
			
		}

	}

}

package com.sqlplus;

import br.com.dreamsource.mobile.jmesql.io.Properties;

public class UserPOJO {


    private String userName;
    private String passwd;
    private String dbName;
    private String connectionURL;
            
    public UserPOJO() {
    }

    public String getUserName() {
        return userName;
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getPasswd() {
        return passwd;
    }

    public void setPasswd(String passwd) {
        this.passwd = passwd;
    }

    public String getDbName() {
        return dbName;
    }

    public void setDbName(String dbName) {
        this.dbName = dbName;
    }
    
    public String getConnectionURL() {
        return connectionURL;
    }

    public void setConnectionURL(String connectionURL) {
        this.connectionURL = connectionURL;
    }
    
    public Properties getAsProperties() {
        Properties p = new Properties();
        p.setProperty("user", this.userName);
        p.setProperty("password", this.passwd);
        p.setProperty("database", this.dbName);
        return p;
    }

}

[xiang1115]

顶

我也正在研究jmesql，就是不知道怎么能创建表格。

[softice_]

没搞过嵌入式数据库，帮顶

[老猫的TOM]

package com.sqlplus;

public class Consts {

    public static final int UPDATE_TYPE_INSERT = 1;
    public static final int UPDATE_TYPE_UPDATE = 2;
    public static final int UPDATE_TYPE_DELETE = 3;
    
    public static final String DATABASE_NAME = "worders";
    public static final String DATABASE_CONNETION_STRING = "jdbc:mesqldb:worders";
    
    public static final String DROP_USER = "DROP USER ?";
    public static final String CREATE_USER = "CREATE USER ? PASSWORD ? admin";

    public static final String DROP_PRICTABLE_TBL = "DROP TABLE priceTable";
    public static final String CREATE_PRICETABLE_TBL = 
            "CREATE TABLE priceTable (" +
            "   id int identity, " +
            "   name varchar(20) not null, " +
            "   percent float not null," +
            "   primary key(id)" +
            ")";
    
    public static final String PRICETABLE_ID = "id";
    public static final String PRICETABLE_NAME = "name";
    public static final String PRICETABLE_PERCENT = "percent";
    
    public static final String PRICETABLE_SELECT_BY_EDIT = "SELECT * FROM pricetable";
    
    public static final String DROP_CUSTOMER_TBL = "DROP TABLE customer";
    public static final String CREATE_CUSTOMER_TBL = 
            "CREATE TABLE customer (" +
            "   id int identity," +
            "   remoteId int," +
            "   priceTableId  int," +
            "   dtRecord date," +
            "   name varchar(80) not null," +
            "   cpf varchar(11)," +
            "   cnpj varchar(14)," +
            "   phone varchar(10) not null," +
            "   fax varchar(10)," +
            "   contact varchar(80) not null," +
            "   mail varchar(80)," +
            "   zipCode varchar(8) not null," +
            "   credit float," +
            "   recordState int not null," +
            "   primary key(id)," +
            "   foreign key(priceTableId) references priceTable(id)" +
            ")";
    
    public static final String CUSTOMER_ID = "id"; 
    public static final String CUSTOMER_REMOTEID = "remoteid"; 
    public static final String CUSTOMER_PRICETABLEID = "pricetableid"; 
    public static final String CUSTOMER_DTRECORD = "dtrecord"; 
    public static final String CUSTOMER_NAME = "name"; 
    public static final String CUSTOMER_CPF = "cpf"; 
    public static final String CUSTOMER_CNPJ = "cnpj"; 
    public static final String CUSTOMER_PHONE = "phone"; 
    public static final String CUSTOMER_FAX = "fax"; 
    public static final String CUSTOMER_CONTACT = "contact"; 
    public static final String CUSTOMER_MAIL = "mail"; 
    public static final String CUSTOMER_ZIPCODE = "zipcode"; 
    public static final String CUSTOMER_CREDIT = "credit"; 
    public static final String CUSTOMER_RECORDSTATE = "recordstate"; 
    
    public static final String CUSTOMER_LOCATE_BY_FIELD = "SELECT id, name FROM customer";
    public static final String CUSTOMER_SELECT_BY_EDIT = 
            "SELECT priceTableId, name, cpf, cnpj, phone, fax, contact, mail, " +
            "zipCode, credit FROM customer";
    
    public static final String CUSTOMER_INSERT = 
            "INSERT INTO customer (remoteId, priceTableId, dtRecord, name, cpf, cnpj, phone, fax, " +
            "contact, mail, zipCode, credit, recordState) VALUES (0, ?, CURDATE(), ?, ?, ?, ?, ?, ?, ?, ?, ?, 0)";
    
    public static final String CUSTOMER_UPDATE = 
            "UPDATE customer set priceTableId = ?, name = ?, cpf = ?, cnpj = ?, phone = ?, fax = ?, " +
            "contact = ?, mail = ?, zipCode = ?, credit = ? where id = ?";
    
    public static final String CUSTOMER_DELETE = 
            "DELETE FROM customer where id = ?";
    
    
}

以上是我项目中的所有源码，如果大家对于存储还有其他什么好的方法或建议，麻烦能写出来参考一下，谢谢了。

[老猫的TOM]

谢谢上面的两位，但本人感觉很孤独，有没有其他高手进来看看

[kazeik]

对数据库不了解.

[老猫的TOM]

问题已解决，不是代码问题，本人也不知为何数据表创建成功返回的boolea值却是false，会不会是javamesql的一个bug？

[老猫的TOM]

本人循环插入数据，貌似达到七千五百行左右报内存溢出。

[Manfeel]

兄弟，我最近也在研究jMeSQL，现在碰到一个更头痛的问题，用insert插入的记录，退出程序后，记录消失。
我查了一下jMeSQL的文档（如果那也算是文档的话！），可能是创建的table默认都在memeory中，于是用
Create cached table,结果，insert数据直接抛异常，我发现是在Cache.java代码中，里面估计是存在某些bug，找了很久也没有结果，我的QQ:179813134，希望交流