dbmanage.java

Java+Eclipse+Mysql的局域网聊天程序源代码

import java.sql.*;
class DbManage
{
	private String url=null;
	private String db_uname=null;
	private String db_password=null;
	
	private String uname=null;
	private String password=null;
	
	private Connection con=null;  //数据库连接
	private Statement stmt=null;  
	
	public DbManage()
	{
		try       //加载驱动程序
		{
		Class.forName("org.gjt.mm.mysql.Driver").newInstance();
		}
		catch(ClassNotFoundException cnfe)
		{
			new Alert().setInfo("没有找到数据库驱动程序");
		}
		catch(InstantiationException ie)
		{
			System.out.println();
		}
		catch(IllegalAccessException iae)
		{
			new Alert().setInfo("没有加载数据库驱动程序的权限");
		}
		ReadConfig rc=new ReadConfig();
		
		this.url="jdbc:mysql://"+rc.getString("dbad", false);
		this.url+=":"+rc.getString("dbpo", false);
		this.url+="/"+rc.getString("dbna", false);
		this.db_uname=rc.getString("dbus", false);
		this.db_password=rc.getString("dbpa", false);

		rc.closeRC();
		Connect();             //
	}

	public void Connect()          //连接数据库
	{
		try
		{
			con=DriverManager.getConnection(url,db_uname,db_password);
			stmt=con.createStatement();
		}
		catch(SQLException sqle)
		{
			new Alert().setInfo("连接数据库失败，请检查连接用户名及密码!");
			try
			{
			if(con!=null)
				con.close();
			}
			catch(SQLException e){}
		}
	}
	public void close()
	{
		try
		{
			stmt.close();
			con.close();
		}
		catch(SQLException sqle)
		{
			new Alert().setInfo("关闭数据库连接时发生异常!");
		}
	}
	public String[] getArray(String sql)
	{
		ResultSet rs=null;
		ResultSetMetaData rsmd=null;
		String tempstr=null;
		try
		{
			rs=stmt.executeQuery(sql);
			rsmd=rs.getMetaData();
			int count=rsmd.getColumnCount();
			int row=0;
			while(rs.next())
			{
				if(row>0)            //划分行
					tempstr+="|";
				for(int i=1;i<=count;i++)
				{
					if(tempstr!=null)
						tempstr=tempstr+","+rs.getString(i);
					else
						tempstr=rs.getString(i);
				}
				row++;
			}
			rs.close();
			if(tempstr!=null)
				return tempstr.split("\\|");
			else
				return null;
		}
		catch(SQLException sqle)
		{
			System.out.println("执行数据库查询语句: "+sql+" 时发生错误");
			return null;
		}
	}
	public boolean updateInfo(String sql)
	{
		try
		{
			if(stmt.executeUpdate(sql)>=0)
				return true;
			return false;
		}
		catch(SQLException sqle)
		{
			System.out.println("执行:\""+sql+"\"时发生异常");
			return false;
		}
	}
	public boolean execute(String sql)
	{
		try
		{
			if(stmt.execute(sql))
				return true;
			return false;
		}
		catch(SQLException sqle)
		{
			System.out.println("执行:\""+sql+"\"时发生异常");
			return false;
		}
	}
}