记账本开发4

今天连接了数据库。

package com.example.myapp0.service;

import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;

public class DatabaseHelper extends SQLiteOpenHelper
{
    static String name="user.db";
    static int dbVersion=1;
    public DatabaseHelper(Context context){super(context, name, null, dbVersion);}
    public void onCreate(SQLiteDatabase db)
    {
        String sql="create table user(id integer primary key autoincrement,je varchar(20),name varchar(20),bz varchar(20)

,rq varchar(20))";
 db.execSQL(sql); 
} 

public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){} }

package com.example.myapp0.service;

import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import com.example.myapp0.User;

public class UserService
{
    private DatabaseHelper dbHelper;
    public UserService(Context context){dbHelper=new DatabaseHelper(context);}
    public boolean login(String username,String password)
    {
        SQLiteDatabase sdb=dbHelper.getReadableDatabase();
        String sql="select * from user where rq=?";
        Cursor cursor=sdb.rawQuery(sql, new String[]{rq});
        if(cursor.moveToFirst()==true)
        {
            cursor.close();
            return true;
        }
        return false;
    }
    public boolean register(User user)
    {
        SQLiteDatabase sdb=dbHelper.getReadableDatabase();
        String sql="insert into user(je,name,bz,rq) values(?,?,?,?)";
        Object obj[]={user.getJe(),user.getName(),user.getBz(),user.getRq()}; 

　　　　 sdb.execSQL(sql, obj); 

　　　　 return true; 
    } 
}

package com.example.myapp0;

import java.io.Serializable;

public class User implements Serializable
{
    private int id;
    private String je;
    private String name;
    private String bz;
    private String rq;
    public User(){super();}
    public User(String je,String name, String bz,String rq)
    {
        super();
        
        this.je = je;
        this.rq = rq;
        this.name = name;
        this.bz = bz;
    }
    public int getId(){return id;}
    public void setId(int id){this.id = id;}
    public String getName(){return name;}
    public void setName(String name){this.name = name;}
    public String getJe(){return je;}
    public void setJe(String je){this.je = je;}
     public String getBz(){return bz;}
    public void setBz(String bz){this.bz = bz;}
    public String getRq(){return rq;}
    public void setRq(String rq){this.rq = rq;}
    public String toString(){return "User [id=" + id + ", je=" + je + ", name=" + name + ", bz=" + bz + ",rq=" + rq + "]";}
}