Question

我有一个数据库管理器类正在创建SQLite Database.Now来自另一个类，我正在创建该类的实例。现在我如何在数据库中插入一个字符串数组？我的数据库管理器类代码如下所示：

     public class DatabaseManager 
{
    public Database sqliteDb = null;
    public DatabaseManager()
    {
        try
        {
            URI myURI = URI.create("/SDCard/databases/itemdb.db");
            Database sqliteDb = DatabaseFactory.openOrCreate(myURI);
            sqliteDb.close();
            sqliteDb = DatabaseFactory.open(myURI);
            Statement statement = sqliteDb.createStatement("CREATE TABLE if not exists SelectedItem (Name TEXT, Quantity TEXT)");
            statement.prepare();
            statement.execute();
            statement.close();
        }
        catch (Exception e) 
        {
            e.printStackTrace();
        }

        finally
          {
               try 
               {
                   if(sqliteDb!=null)
                   {
                       sqliteDb.close();
                   }

               } 
               catch (Exception e) 
               {
                e.printStackTrace();
               }
          }
    }

    public static void insertValues(String tableName, Hashtable ht)
    {
        try 
        {
            Logger.out("Grocery", "it is comin here");
            URI myURI = null;
            try 
            {
                myURI = URI.create("/SDCard/databases/itemdb.db");
            } 
            catch (IllegalArgumentException e) 
            {
                e.printStackTrace();
            } 
            catch (MalformedURIException e) 
            {
                e.printStackTrace();
            }
            Database sqliteDb = DatabaseFactory.openOrCreate(myURI);
            sqliteDb.close();
            sqliteDb = DatabaseFactory.open(myURI);
            Statement dbStatement = sqliteDb.createStatement("INSERT INTO  SelectedItem(Name,Quantity) " + "VALUES (?,?)");
            Enumeration itemName = ht.keys();
            Enumeration itemQty = ht.elements();
            while(itemName.hasMoreElements())
            {
                Logger.out("Grocery", "more items");
                String strName = itemName.nextElement().toString();
                String strQty = itemQty.nextElement().toString();
                Logger.out("Grocery", "name:" + "   " + strName);
                Logger.out("Grocery", "QTY:" + "    " + strQty);
                dbStatement.bind(1, strName);
                dbStatement.bind(2, strQty);
                Logger.out("Grocery", "Binded:::::::::");
                dbStatement.execute();
                dbStatement.reset();
                Logger.out("Grocery", "Executed:::::::::");
            }
            dbStatement.close();
        }
        catch (DatabaseException e) 
        {
            e.printStackTrace();
        }
    }

    public void closeDb() 
    {
        try 
        {
            sqliteDb.close();
        } 
        catch (DatabaseIOException e) 
        {
            e.printStackTrace();
        }

    }

}

现在我将名称和数量作为哈希表。在我的主要课程中，当我按下按钮时，我将数据库中的值插入如下：

dbManager  = new DatabaseManager();
    dbManager.insertValues("SelectedItem", htItem);

Answer 1

如果您想将另一个类方法用作globle，请尝试以下方法，然后将其声明为static。多行插入的genaral查询是

INSERT INTO'tablename'SELECT'data1'AS'column1'，'data2'AS 'column2'UNION SELECT'data3'，'data4'UNION SELECT'data5'，'data6' UNION SELECT'data7'，'data8'

import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.FieldChangeListener;
import net.rim.device.api.ui.UiApplication;
import net.rim.device.api.ui.component.ButtonField;
import net.rim.device.api.ui.component.LabelField;
import net.rim.device.api.ui.container.MainScreen;
public class SampleDatabase extends UiApplication 
{
    LabelField test;
    String names[];
    int ages[];
    MainScreen screen = new MainScreen();
    public static void main(String[] args)
    {
        SampleDatabase theApp = new SampleDatabase();
        theApp.enterEventDispatcher();
    }

    public SampleDatabase()
    {
        ButtonField btn=new ButtonField("Click");
        names=new String[10];
        ages=new int[10];
        for(int i=0;i<10;i++)
        {
            names[i]="Govind"+i;
            ages[i]=i;
        }
        btn.setChangeListener(new FieldChangeListener() {


            public void fieldChanged(Field field, int context) {
                synchronized (UiApplication.getEventLock()) {
                    databaseOperations.DatabaseManager();
                    databaseOperations.InsertDatabaseManager(names,ages);
                }

            }
        });
        screen.add(btn);
        pushScreen(screen);
    }
}

这是另一个名为“databaseOperations.java”的类

import net.rim.device.api.database.Database;
import net.rim.device.api.database.DatabaseFactory;
import net.rim.device.api.database.Statement;
import net.rim.device.api.io.URI;

public class databaseOperations {

     public static void DatabaseManager()
      {
          Database d=null;
        try {
                  URI uri = URI.create("file:///SDCard/Databases/SQLite_Guide/" + 
                                        "MyTestDatabase.db");
                  d = DatabaseFactory.openOrCreate(uri);
                  d.close();
                  d = DatabaseFactory.open(uri);
                  Statement s = d.createStatement( "CREATE TABLE if not exists 'People' ( " +
                          "'Name' TEXT, " +
                          "'Age' INTEGER )");
                  s.prepare();
                  s.execute();
                  s.close();
            }
       catch(Exception e)
        {
          e.printStackTrace();
        } 
       finally
       {
           try {
               if(d!=null)
               {
                   d.close();
               }

        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
       }
      }
      public static void InsertDatabaseManager(String[] names,int ages[])
      {
          Database d=null;
        try {
                  URI uri = URI.create("file:///SDCard/Databases/SQLite_Guide/" + 
                                        "MyTestDatabase.db");
                  d = DatabaseFactory.openOrCreate(uri);
                  d.close();
                  d = DatabaseFactory.open(uri);

                  String query="INSERT INTO 'People' SELECT '"+names[0]+"' AS 'Name', "+ages[0]+" AS 'Age'";
                  String query2="";
                  for(int i=1;i<names.length;i++)
                  {
                      query2=query2+" UNION SELECT '"+names[i]+"', "+ages[i];
                  }
                  System.out.println(query+query2);
                  Statement s = d.createStatement(query+query2);
                  s.prepare();
                  s.execute();
                  s.close();
            }
       catch(Exception e)
        {
          e.printStackTrace();
        } 
        finally
        {
           try {
               if(d!=null)
               {
                   d.close();
               }

          } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
       }
      }
}

如何在黑莓中的SQLite数据库中插入一个String数组

1 个答案: