datarecordstoretest.java

来自「J2ME开发实例,内含有可直接运行的源程序代码,供大家学习参考」· Java 代码 · 共 142 行

//DataRecordStoreTest.java
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.rms.* ;
import java.io.*;
class FriendData
{
	String name ;
	String tel ;
	boolean sex ;
	int age ;
	public FriendData()
	{
		name = "NO NAME" ;
		name = "NO TEL" ;
		sex = false ;
		age = 0 ;
	}
	public byte[] encode()
	{
		byte[] result = null ;
		try
		{
			ByteArrayOutputStream bos =
				new ByteArrayOutputStream() ;
			DataOutputStream dos =
				new DataOutputStream (bos) ;
			dos.writeUTF(name) ;
			dos.writeUTF(tel) ;
			dos.writeBoolean(sex) ;
			dos.writeInt(age) ;
			result = bos.toByteArray() ;
			dos.close() ;
			bos.close() ;
		}
		catch(Exception e)
		{ }
		return result ;
	}
	public void decode(byte[] data)
	{
		try
		{
			ByteArrayInputStream bis =
				new ByteArrayInputStream(data) ;
			DataInputStream dis =
				new DataInputStream (bis) ;
			name = dis.readUTF() ;
			tel = dis.readUTF() ;
			sex = dis.readBoolean() ;
			age = dis.readInt() ;
			dis.close() ;
			bis.close() ;
		}
		catch(Exception e)
		{ }
	}
}
public class DataRecordStoreTest extends MIDlet implements ItemStateListener
{
	private Display display;
	public DataRecordStoreTest()
	{
		display = Display.getDisplay(this);
	}
	public void startApp()
	{
		String dbname = "testdb" ;
		Form f = new Form("RS Test") ;
		RecordStore rs = openRSAnyway(dbname) ;
		if( rs == null )
		{
			f.append("Table open fail") ;
		}
		else
		{
			try
			{
				FriendData fd = new FriendData() ;
				fd.name = "李小明" ;
				fd.tel = "62759933" ;
				fd.sex = false ;
				fd.age = 17 ;
				byte tmp[] = fd.encode() ;
					int id = rs.addRecord(tmp,0,tmp.length) ;
				FriendData fd2 = new FriendData() ;
				fd2.decode(rs.getRecord(id)) ;
				f.append("姓名:"+ fd2.name) ;
				f.append("\n 电話:"+ fd2.tel) ;
				if(fd2.sex)
				{
					f.append("\n 性別: 男") ;
				}
				else
				{
					f.append("\n 性別: 女") ;
				}
				f.append("\n 年龄:"+ fd2.age) ;
				rs.closeRecordStore() ;
				deleteRS(dbname) ;
			}
			catch(Exception e){}
			display.setCurrent(f) ;
		}
	}
	public void pauseApp()
	{ }
	public void destroyApp(boolean unconditional)
	{ }
	public void itemStateChanged(Item item)
	{ }
	public RecordStore openRSAnyway(String rsname)
	{
		RecordStore rs = null ;
		if(rsname.length() > 32)
			return null ;
		try
		{
			rs = RecordStore.openRecordStore(rsname,true) ;
			return rs ;
		}
		catch(Exception e)
		{
			return null ;
		}
	}
	public boolean deleteRS(String rsname)
	{
		if(rsname.length() > 32)
			return false ;
		try
		{
			RecordStore.deleteRecordStore(rsname) ;
		}
		catch(Exception e)
		{
			return false ;
		}
		return true ;
	}
}