midlet1.java

这是郭克华老师的J2ME视频的源代码

package prj16_1;

import javax.microedition.midlet.MIDlet;
import javax.microedition.midlet.MIDletStateChangeException;
import javax.microedition.rms.RecordEnumeration;
import javax.microedition.rms.RecordStore;

public class MIDlet1 extends MIDlet {

	protected void startApp() throws MIDletStateChangeException {
		RecordStore rs = null;
		try{
			rs = RecordStore.openRecordStore("RS1", true);
			rs.addRecord("中国".getBytes(), 0, 4);
			rs.addRecord("美国".getBytes(), 0, 4);
			rs.addRecord("韩国".getBytes(), 0, 4);
			rs.addRecord("日本".getBytes(), 0, 4);
			rs.addRecord("德国".getBytes(), 0, 4);
			
			//getNextRecordId遍历
			rs.deleteRecord(3);
			int nextId = rs.getNextRecordID();
			for(int i=1;i<nextId;i++){
				try{
					System.out.println(new String(rs.getRecord(i)));
				}catch(Exception ex){}
			}
			
			
			
			/*枚举遍历,能够自动发现并判断被删除的纪录，性能较好
			rs.deleteRecord(3);
			RecordEnumeration re = rs.enumerateRecords(null, null, false);
			while(re.hasNextElement()){
				System.out.println(new String(re.nextRecord()));
			}*/
			
			
			
			
			
			
			/*遍历，以下代码错误
			rs.deleteRecord(3);
			int num = rs.getNumRecords();
			for(int i=1;i<=num;i++){
				System.out.println(new String(rs.getRecord(i)));
			}*/
			
			
		}catch(Exception ex){
			ex.printStackTrace();
		}
		finally{
			try{
				rs.closeRecordStore();
			}catch(Exception ex){}
		}

	}

	protected void destroyApp(boolean arg0) throws MIDletStateChangeException {
		// TODO Auto-generated method stub

	}

	protected void pauseApp() {
		// TODO Auto-generated method stub

	}



}