j2me工具类：Database.java

/**
 * <p>Title: </p>
 *
 * <p>Description: </p>
 *
 * <p>Copyright: Copyright (c) 2008</p>
 *
 * <p>Company: WorthTech</p>
 *
 * @author bruce
 * @version 1.0
 */
import javax.microedition.rms.*;

//import java.io.*;
//import java.util.Hashtable;

//import com.mpay.io.SerializerInputStream;
//import com.mpay.io.SerializerOutputStream;
//import com.mpay.io.SerializationException;
//import com.mpay.util.commlib.info.MenuInfo;
//import com.mpay.util.commlib.ByteArray;
//import com.mpay.util.commlib.info.BillInfo;

//import com.mpay.util.commlib.TypeConvert;

public class Database {
	private RecordStore store;

	public static Database instance;

	public Database() {
	}

	public static Database getDatabase() {
		if (instance == null) {
			instance = new Database();
		}
		return instance;
	}

	public void open(String tableName) {
		try {
			this.store = RecordStore.openRecordStore(tableName, true);
		} catch (RecordStoreException ex) {
			ex.printStackTrace();
			//System.out.println("打开数据库出错:" + ex.getMessage());
			try {
				store.closeRecordStore();
				store = null;
			} catch (Exception e) {
				e.printStackTrace();
			}
		}
	}

	public int getNumRecords() {
		try {
			return this.store.getNumRecords();
		} catch (RecordStoreNotOpenException ex) {
			ex.printStackTrace();
			//System.out.println("未找到记录" + ex.getMessage());
			return 0;
		}
	}

	public void close() {
		try {
			this.store.closeRecordStore();
		} catch (RecordStoreNotOpenException ex) {
			ex.printStackTrace();
			//System.out.println("数据库尚未打开:" + ex.getMessage());
		} catch (RecordStoreException ex) {
			ex.printStackTrace();
			//System.out.println("数据库关闭出错:" + ex.getMessage());
		}
	}

	public int addRecord(String content) {
		byte[] data = content.getBytes();
		try {
			return this.store.addRecord(data, 0, data.length);
		} catch (RecordStoreNotOpenException ex) {
			ex.printStackTrace();
			//System.out.println("数据库尚未打开:" + ex.getMessage());
		} catch (RecordStoreException ex) {
			ex.printStackTrace();
			//System.out.println("写入数据出错:" + ex.getMessage());
		}
		return -1;
	}

	public int addRecord(byte[] data) {
		try {
			return this.store.addRecord(data, 0, data.length);
		} catch (RecordStoreNotOpenException ex) {
			ex.printStackTrace();
			//System.out.println("数据库尚未打开:" + ex.getMessage());
		} catch (RecordStoreException ex) {
			ex.printStackTrace();
			//System.out.println("写入数据出错:" + ex.getMessage());
		}
		return -1;
	}

//	public int addRecord(Object obj) {
//		ByteArrayOutputStream baos = new ByteArrayOutputStream();
//		SerializerOutputStream out = null;
//		try {
//			out = new SerializerOutputStream(baos);
//			if (obj instanceof MessageInfo) {
//				((MessageInfo) obj).serialize(out);
//			} else if (obj instanceof MenuInfo) {
//				((MenuInfo) obj).serialize(out);
//			} else if (obj instanceof Constants) {
//				((Constants) obj).serialize(out);
//			} else if (obj instanceof BillInfo) {
//				((BillInfo) obj).serialize(out);
//			}
//			out.flush();
//			byte[] data = baos.toByteArray();
//			return this.addRecord(data);
//		} catch (SerializationException ex) {
//			ex.printStackTrace();
//			//System.out.println("序列化对象时异常:" + ex.getMessage());
//		} catch (IOException e) {
//			e.printStackTrace();
//			//System.out.println("序列化对象存储时异常:" + e.getMessage());
//		} finally {
//			try {
//				if (out != null) {
//					out.close();
//				}
//				if (baos != null) {
//					baos.close();
//				}
//			} catch (IOException ex1) {
//				ex1.printStackTrace();
//			}
//		}
//		return -1;
//	}

	public byte[] getRecord(int recordId) {
		try {
			return this.store.getRecord(recordId);
		} catch (InvalidRecordIDException ex) {
			ex.printStackTrace();
			//System.out.println("不正确的记录ID索引" + ex.getMessage());
			return null;
		} catch (RecordStoreNotOpenException ex) {
			ex.printStackTrace();
			//System.out.println("数据库尚未打开:" + ex.getMessage());
			return null;
		} catch (RecordStoreException ex) {
			ex.printStackTrace();
			//System.out.println("读取数据出错:" + ex.getMessage());
			return null;
		}
	}

//	public Object getMessageRecord(int recordId, Object obj) {
//		Object object = obj;
//		//        //System.out.println("recordId=" + recordId);
//		byte[] data = this.getRecord(recordId);
//		//        //System.out.println("data[]==" + TypeConvert.toHexString(data));
//
//		ByteArrayInputStream bais = new ByteArrayInputStream(data);
//		SerializerInputStream in = new SerializerInputStream(bais);
//		try {
//			if (obj instanceof MessageInfo) {
//				ByteArray array = new ByteArray();
//				array.add(data);
//				object = new MessageInfo(data);
//				((MessageInfo) object).deserialize(in);
//			} else if (obj instanceof MenuInfo) {
//				((MenuInfo) object).deserialize(in);
//			} else if (obj instanceof Constants) {
//				((Constants) object).deserialize(in);
//			} else if (obj instanceof BillInfo) {
//				((BillInfo) object).deserialize(in);
//			}
//		} catch (SerializationException ex) {
//			ex.printStackTrace();
//			//System.out.println("反序列化对象时异常:" + ex.getMessage());
//		} finally {
//			try {
//				if (in != null) {
//					in.close();
//				}
//				if (bais != null) {
//					bais.close();
//				}
//			} catch (IOException ie) {
//				ie.printStackTrace();
//			}
//		}
//		return object;
//	}

	public void updateRecord(int recordId, byte[] newdata) {
		try {
			this.store.setRecord(recordId, newdata, 0, newdata.length);
		} catch (InvalidRecordIDException ex) {
			ex.printStackTrace();
			//System.out.println("不正确的记录ID索引" + ex.getMessage());
		} catch (RecordStoreNotOpenException ex) {
			ex.printStackTrace();
			//System.out.println("数据库尚未打开:" + ex.getMessage());
		} catch (RecordStoreException ex) {
			ex.printStackTrace();
			//System.out.println("读取数据出错:" + ex.getMessage());
		}
	}

	public void updateRecord(int recordId, String newdata) {
		byte[] data = newdata.getBytes();
		try {
			this.store.setRecord(recordId, data, 0, data.length);
		} catch (InvalidRecordIDException ex) {
			ex.printStackTrace();
			//System.out.println("不正确的记录ID索引" + ex.getMessage());
		} catch (RecordStoreNotOpenException ex) {
			ex.printStackTrace();
			//System.out.println("数据库尚未打开:" + ex.getMessage());
		} catch (RecordStoreException ex) {
			ex.printStackTrace();
			//System.out.println("读取数据出错:" + ex.getMessage());
		}
	}

//	public void updateRecord(int recordId, Object obj) {
//		ByteArrayOutputStream baos = new ByteArrayOutputStream();
//		SerializerOutputStream out = null;
//		try {
//			out = new SerializerOutputStream(baos);
//			if (obj instanceof MessageInfo) {
//				((MessageInfo) obj).serialize(out);
//			} else if (obj instanceof MenuInfo) {
//				((MenuInfo) obj).serialize(out);
//			} else if (obj instanceof Constants) {
//				((Constants) obj).serialize(out);
//			} else if (obj instanceof BillInfo) {
//				((BillInfo) obj).serialize(out);
//			}
//			out.flush();
//			byte[] data = baos.toByteArray();
//			this.updateRecord(recordId, data);
//		} catch (SerializationException ex) {
//			ex.printStackTrace();
//			//System.out.println("序列化对象时异常:" + ex.getMessage());
//		} catch (IOException ie) {
//			ie.printStackTrace();
//			//System.out.println("序列化对象存储时异常:" + ie.getMessage());
//		} finally {
//			try {
//				if (out != null) {
//					out.close();
//				}
//				if (baos != null) {
//					baos.close();
//				}
//			} catch (IOException ex1) {
//				ex1.printStackTrace();
//			}
//		}
//	}

	public void deleteRecord(int recordId) {
		try {
			this.store.deleteRecord(recordId);
		} catch (InvalidRecordIDException ex) {
			ex.printStackTrace();
		} catch (RecordStoreNotOpenException ex) {
			ex.printStackTrace();
		} catch (RecordStoreException ex) {
			ex.printStackTrace();
		}
	}

	public void clearTable(String tableName) {
		try {
			Thread.currentThread().sleep(1000);
			this.store.deleteRecordStore(tableName);
		} catch (InterruptedException ie) {
			ie.printStackTrace();
		} catch (RecordStoreException ex) {
			ex.printStackTrace();
			//System.out.println("删除数据库出错:" + ex.getMessage());
			try {
				Thread.currentThread().sleep(1000);
				this.store.deleteRecordStore(tableName);
			} catch (InterruptedException ie) {
				ie.printStackTrace();
			} catch (RecordStoreException rs) {
				rs.printStackTrace();
			}
		}
	}

}