msdb.java

服务器tomcat 数据库mysql Hospital Management System 为医院的门诊

/*
 * DB.java
 *
 * Created on 2006年3月3日, 上午9:42
 */

package mysql;   // change package

/**
 *
 * @author Star
 */
import java.sql.*;
import java.security.*;
import java.security.spec.*;
import java.io.*;

public class msdb
{

	private Connection con=null;
	private Statement stmt=null;
	ResultSet rs=null;


	/*
	 *加载驱动
	*/
	public msdb(){
		try{
			Class.forName ("com.mysql.jdbc.Driver");
		}
		catch(ClassNotFoundException e){
			System.err.println("DB():"+e.toString());
			System.exit(1);
		}
		catch(Exception e){
			System.err.println("DB():"+e.toString());
			System.exit(1);
		}
	}

	/*
	 *得到连接
	*/
	public Connection getConnection(){
		try{
			con=DriverManager.getConnection("jdbc:mysql:///board?user=root&password="); 
		}
		catch(Exception e){
			System.err.println("getConnection():"+e.toString());
			con=null;
		}
		return con;
	}

	/*
	 *关闭连接 
	*/
	public void dropConnection(){
		try{
			closeStmt();
			con.close();
		}
		catch(Exception ignored){
			
		}
		finally{
			con=null;
		}
	}

	/*
	 *执行SQL查询
在为 Connection 创建 Statement 时，可以将 Result
Set 的类型更改为更为灵活的可滚动或可更新模型，如下所示：
Statement stmt = con.createStatement(ResultSet.TYPE_FORWARD_ONLY, Resu
ltSet.CONCUR_READ_ONLY);
ResultSet rs = stmt.executeQuery("SELECT * FROM Sells");
不同的类型选项： TYPE_FORWARD_ONLY 、 TYPE_SCROLL_INSENSITIVE 和 TYPE_SCROLL
_SENSITIVE 。可以通过使用 CONCUR_READ_ONLY 和 CONCUR_UPDATABLE 选项来选择光标
是只读的还是可更新的
	*/
	public ResultSet executeQuery(String sql){
		rs=null;
		try{
			con=getConnection();
			stmt=con.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);

			rs=stmt.executeQuery(sql);
		}
		catch(SQLException ex){
			System.err.println("excuteQuery():"+ex.getMessage());
		}
		return rs;
	}

	/*
	 *执行SQL更新
	*/
	public void executeUpdate(String sql){
		rs=null;
		try{
			con=getConnection();
			stmt=con.createStatement();
			stmt.executeUpdate(sql);
			stmt.close();
			con.close();
		}
		catch(SQLException ex){
			System.err.println("excuteUpdate():"+ex.getMessage());
		}
	}

	/*
	 *执行SQL语句
	*/
	public void execute(String sql){
		stmt=null;
		rs=null;
		try{
			con=getConnection();
			stmt=con.createStatement();
			stmt.execute(sql);
			stmt.close();
			con.close();
		}
		catch(SQLException ex){
			System.err.println("excute():"+ex.getMessage());
		}
	}

	/*
	 *关闭SQL语句
	*/
	public void closeStmt(){
		try{
			stmt.close();
		}
		catch(SQLException e){
			e.printStackTrace();
		}
	}

	/*
	 *关闭SQL连接
	*/
	public void closeConn(){
		try{
			con.close();
		}
		catch(SQLException e){
			e.printStackTrace();
		}
	}

/////////Unicode//////////////Mysql 从 4.1才开始支持Unicode/////////////////////////////////
 public String native2Unicode(String s) {
            if (s == null || s.length() == 0) {
               return null;
       	    }
            byte[] buffer = new byte[s.length()];
            for (int i = 0; i < s.length(); i++) {
               buffer[i] = (byte)s.charAt(i);
            }
            return new String(buffer);
        }       
        
	public	String unicode2Native(String s) {
           if (s == null || s.length() == 0) {
              return null;
           }
           char[] buffer = new char[s.length() * 2];
           char c;
           int j = 0;
           for (int i = 0; i < s.length(); i++) {
              if (s.charAt(i) >= 0x100) {
                 c = s.charAt(i);
                 byte []buf = (""+c).getBytes();
                 buffer[j++]  = (char)buf[0];
                 buffer[j++]  = (char)buf[1];
              }
              else {
                 buffer[j++] = s.charAt(i);
              }
	   }
           return new String(buffer, 0, j);
	}
///////////////从Mysql读中文/////////////////////////////////////////////
  public String native2Iso(String s) {
           
   try{
	       if (s == null || s.length() == 0) 
               return null;
       	      else  
            return new String(s.getBytes("ISO8859-1"));
        }
            catch(Exception e)
	{
	   return null;
		} 
        
}      
        

///////////////////////////////////////
public String MD5(String s){
char hexDigits[] = {
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd',
'e', 'f'};
try {
byte[] strTemp = s.getBytes();
MessageDigest mdTemp = MessageDigest.getInstance("MD5");
mdTemp.update(strTemp);
byte[] md = mdTemp.digest();
int j = md.length;
char str[] = new char[j * 2];
int k = 0;
for (int i = 0; i < j; i++) {
byte byte0 = md[i];
str[k++] = hexDigits[byte0 >>> 4 & 0xf];
str[k++] = hexDigits[byte0 & 0xf];
}
return new String(str);
}
catch (Exception e){
return null;
}
}


  }