mid.java~24~

J2ME的一个简单例子

package j2me;
import java.io.*;
import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;
import javax.microedition.rms.*;

public class Mid extends MIDlet
implements CommandListener {

  private Command exitCommand;
  private Display display;
  private String[] names = {"\u00BB\u00C6\u00B4\u00CF\u00C3÷","\u00B3\u00C2\u00D0\u00A1ó\u00E3","\u00BB\u00C6\u00D5ò\u00D5\u00C1","\u00D6\u00A3\u00D1\u00C5\u00CE\u00C4"};
  private int[] chineseScore = {74,98,89,76};
  private int[] englishScore = {67,89,89,78};
  private int[] mathScore = {80,76,80,78};

  public Mid() {
    display = Display.getDisplay(this);
    exitCommand = new Command("\u00C0\u00EB\u00BF\u00AA", Command.EXIT, 1);
  }

  public void startApp() {
        TextBox aTextBox = new TextBox("\u00D6÷\u00BB\u00AD\u00C3\u00E6",null,256,TextField.ANY);

        RecordStore rs = null;
        byte[] nameEmail=null;
        boolean existingOrNot = false;
        boolean OK = true;

        existingOrNot = existing("aRS3");
        if(existingOrNot){
           try{
                rs = RecordStore.openRecordStore("aRS3",false);
            }
            catch(Exception e){
                OK = false;
           }
           finally{
                 if(OK){
                         aTextBox.setString("aRS3\u00D2\u00D1\u00B4\u00E6\u00D4\u00DA\u00B2\u00A2\u00C7\u00D2\u00D2\u00D1\u00B4ò\u00BF\u00AA");
                  }
                  else{
                        aTextBox.setString("aRS3\u00D2\u00D1\u00B4\u00E6\u00D4\u00DA\u00B5\u00AB\u00CE\u00DE·¨\u00B4ò\u00BF\u00AA");
                  }
            }
        }
        else{
        try{
                rs = RecordStore.openRecordStore("aRS3",true);
            }
             catch(Exception e){
                OK = false;
            }
            finally{
                if(OK){
                    aTextBox.setString("aRS3\u00CB\u00E4\u00CE\u00B4\u00B4\u00E6\u00D4\u00DA,\u00B5\u00AB\u00D2\u00D1\u00B4\u00B4\u00BD¨\u00B2\u00A2\u00CDê\u00B3\u00C9\u00B4ò\u00BF\u00AA\u00B5\u00C4\u00B2\u00D9×÷!");
                }
                else{
                    aTextBox.setString("aRS3\u00CB\u00E4\u00CE\u00B4\u00B4\u00E6\u00D4\u00DA,\u00B5\u00AB\u00CE\u00DE·¨\u00B4\u00B4\u00BD¨,\u00B4ò\u00BF\u00AA\u00CE\u00C4\u00BC\u00FE\u00CA§°\u00DC!");
                }
        }
        }

    Student aStudent = null;

    if(OK)
       try{
                   for(int i=0;i<names.length;i++){
                          aStudent = new Student();
                          aStudent.write(names[i],
                                         chineseScore[i],
                                         englishScore[i],
                                         mathScore[i]
                                        );
                      byte[] data = aStudent.changeToByteArray();
                      int recordID = aStudent.getRecordID();
                      if(recordID != -1){
                        rs.setRecord(recordID,data,0,data.length);
                          }
                      else{
                                recordID = rs.addRecord(data,0,data.length);
                                  aStudent.setRecordID(recordID);
                            }
                            aStudent = null;
                    }
                        aTextBox.setString("\u00D2\u00D1\u00CDê\u00B3\u00C9\u00D0\u00C2\u00D4\u00F6\u00BC\u00C7\u00C2\u00BC\u00B5\u00C4\u00B2\u00D9×÷!");
                  }
           catch(Exception e){
                        aTextBox.setString("\u00D0\u00C2\u00D4\u00F6\u00BC\u00C7\u00C2\u00BC\u00B5\u00C4\u00B2\u00D9×÷\u00CA§°\u00DC!");
           }

    String result="";
    aStudent = new Student();


    if(OK)
       try{
                   byte[] data;
                   int number = 0;

                 result += "\u00B9\u00B2\u00D3\u00D0" + number + "±\u00CA\u00BC\u00C7\u00C2\u00BC:\n";
                    aTextBox.setString(result);
                  }
           catch(Exception e){
                   aTextBox.setString("\u00BB\u00F1\u00C8\u00A1\u00BC\u00C7\u00C2\u00BC\u00B5\u00C4\u00B2\u00D9×÷\u00CA§°\u00DC!"  );
                   try{
                                rs.closeRecordStore();
                                System.out.println("1.Closed.");
                        RecordStore.deleteRecordStore("aRS3");
                                System.out.println("delete OK");
                        }
                        catch(Exception x){
            }
           }
    finally{
           try{
                   if(rs != null) rs.closeRecordStore();
                   rs.deleteRecordStore("aRS3");
           }
           catch(Exception e){
           }
        }

    aTextBox.setString(result);
    aTextBox.addCommand(exitCommand);
    aTextBox.setCommandListener(this);
    display.setCurrent(aTextBox);
  }

  public void pauseApp() {
  }
  public void destroyApp(boolean unconditional) {
  }

  public boolean existing(String recordStoreName) {
    boolean existingOrNot = false;
    RecordStore rs = null;
    if(recordStoreName.length() > 32) return false;
    try{
            rs = RecordStore.openRecordStore(recordStoreName,false);
    }
    catch(RecordStoreNotFoundException e){
            existingOrNot = false;
    }
    catch(Exception e){
    }
    finally{
            try{
                rs.closeRecordStore();
            }
            catch(Exception e){
            }
    }
   return existingOrNot;
  }

  public void commandAction(Command c, Displayable s) {
     destroyApp(false);
     notifyDestroyed();
  }
}


class Student{
    private int ID = -1;
    private String name;
    private int chineseScore;
    private int englishScore;
    private int mathScore;

    public void write(String name,int chineseScore,int englishScore,int mathScore){
     this.name = name;
     this.chineseScore = chineseScore;
     this.englishScore = englishScore;
     this.mathScore = mathScore;
    }

    public void setRecordID(int ID){
      this.ID = ID;
    }

    public int getRecordID(){
      return ID;
    }

    public byte[] changeToByteArray(){
      byte[] data = null;

      try{
       ByteArrayOutputStream baos = new ByteArrayOutputStream();
       DataOutputStream dos = new DataOutputStream(baos);
       dos.writeUTF(name);
       dos.writeInt(chineseScore);
       dos.writeInt(englishScore);
       dos.writeInt(mathScore);
       data = baos.toByteArray();

       baos.close();
       dos.close();
       }
       catch(Exception e){
       }
       return data;
     }

    public void changeFromByteArray(byte[] data){
       try{
        ByteArrayInputStream bais = new ByteArrayInputStream(data);
        DataInputStream dis = new DataInputStream(bais);

        name = dis.readUTF();
        chineseScore = dis.readInt();
        englishScore = dis.readInt();
        mathScore = dis.readInt();

        bais.close();
        dis.close();
        }
        catch(Exception e){
        }
       }

    public String getName(){
        return name;
    }

    public int getChineseScore(){
        return chineseScore;
    }

    public int getEnglishScore(){
        return englishScore;
    }

    public int getMathScore(){
        return mathScore;
    }
}