java.io.EOFException 一直报这个错误

不知为什么一直报这个错误：
java.io.EOFException
at java.io.DataInputStream.readFully(+48)
at java.io.DataInputStream.readUTF(+30)
at java.io.DataInputStream.readUTF(+4)
at gesanri.SetCanvas. <init>(+295)
at gesanri.MainCanvas.commandAction(+31)
 

做一个天气预报，可以保存要显示的城市名称
在增加城市页面，我的rms关键操作如下（其中SetCanvas.cityName是一个Vector，用来保存城市名，在执行此段代码之前，我已经把新增加的城市名添加进了这个Vector
 

Java code

try { recordstore = RecordStore.openRecordStore("cityStore", true);   } catch (Exception e) { e.printStackTrace();   }      try { byte[] outputRecord; String city = null; ByteArrayOutputStream outputStream = new ByteArrayOutputStream(); DataOutputStream outputDataStream = new DataOutputStream(outputStream);  for(int i = 0; i < SetCanvas.cityName.size(); i++){ city = (String)SetCanvas.cityName.elementAt(i); outputDataStream.writeUTF(city); } outputDataStream.writeInt(SetCanvas.cityName.size()); outputDataStream.flush(); outputRecord = outputStream.toByteArray(); recordstore.setRecord(1,outputRecord, 0, outputRecord.length); outputStream.reset(); outputStream.close(); outputDataStream.close();   } catch (Exception e) { e.printStackTrace();   }   try { recordstore.closeRecordStore();   } catch (Exception e) { e.printStackTrace();   } 

SetCanvas里的rms关键操作如下,这里首先判断了如果是初次运行这个程序，则添加北京、上海、重庆3个城市
 

Java code

try {  recordstore = RecordStore.openRecordStore("cityStore", true);  if(recordstore.getNumRecords() == 0){   byte[] outputRecord;   ByteArrayOutputStream outputStream = new ByteArrayOutputStream();   DataOutputStream outputDataStream = new DataOutputStream(outputStream);   outputDataStream.writeUTF("北京");   outputDataStream.writeUTF("上海");   outputDataStream.writeUTF("重庆");   outputDataStream.writeInt(3);   outputDataStream.flush();   outputRecord = outputStream.toByteArray();   recordstore.addRecord(outputRecord, 0, outputRecord.length);   outputStream.reset();   outputStream.close();   outputDataStream.close();      cityName.addElement("北京");   cityName.addElement("上海");   cityName.addElement("重庆");  }  else{   cityName.removeAllElements();   String inputString = null;   int inputInteger = 0;   byte[] byteInputData = new byte[100];   ByteArrayInputStream inputStream = new ByteArrayInputStream(byteInputData);   DataInputStream inputDataStream = new DataInputStream(inputStream);   recordstore.getRecord(1,byteInputData,0);   inputInteger = inputDataStream.readInt();   for(int i = 0; i < inputInteger; i++){ inputString = inputDataStream.readUTF(); cityName.addElement(inputString);   }   inputStream.reset();   inputStream.close();   inputDataStream.close();  }  }catch (Exception e) {  e.printStackTrace();  }  try {  recordstore.closeRecordStore();  } catch (Exception e) {  e.printStackTrace();  } 

------解决方法--------------------------------------------------------
 

Java code

//write ByteArrayOutputStream outputStream = new ByteArrayOutputStream(); DataOutputStream outputDataStream = new DataOutputStream(outputStream); outputDataStream.writeInt(SetCanvas.cityName.size());//先写size for(int i = 0; i < SetCanvas.cityName.size(); i++){ city = (String)SetCanvas.cityName.elementAt(i); outputDataStream.writeUTF(city); } outputRecord = outputStream.toByteArray(); recordstore.setRecord(1,outputRecord, 0, outputRecord.length);   outputDataStream.close();//readByteArrayInputStream inputStream = new ByteArrayInputStream(byteInputData);   DataInputStream inputDataStream = new DataInputStream(inputStream);   recordstore.getRecord(1,byteInputData,0);   inputInteger = inputDataStream.readInt();   for(int i = 0; i < inputInteger; i++){ inputString = inputDataStream.readUTF(); cityName.addElement(inputString);   }   inputDataStream.close();