JDBC连接数据库代码

public class DBTools {
    private Connection con;

    private Statement stmt;

    String driver = "com.informix.jdbc.IfxDriver";

    String url = "jdbc:informix-sqli://58.1.1.5:2111/szbftest:INFORMIXSERVER=szjz11";
   
    String username = "sz2000";

    String password = "2004sz";

    public DBTools() {
        try {
            Class.forName(driver);
        } catch (ClassNotFoundException e) {
            System.out.println("找不到驱动程序类 ，加载驱动失败！");
            e.printStackTrace();
        }
        try {
            con = DriverManager.getConnection(url, username, password);
            stmt = con.createStatement();       
        } catch (SQLException se) {
            System.out.println("数据库连接失败！");
            se.printStackTrace();
        }
    }

    // 测试程序
    public static void main(String[] args) {
        DBTools db = new DBTools();
        String sql = "select * from tableName";
        ResultSet rs = db.sendQuery(sql);
        try {
            if (rs != null) {
                while (rs.next()) {
                    System.out.println(rs.getString("tasktype") + " " + rs.getString("status"));
                }
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }

    // 处理查询
    public ResultSet sendQuery(String sql) {
        try {
            ResultSet rs = stmt.executeQuery(sql);
            return rs;
        } catch (SQLException e) {
            e.printStackTrace();
            return null;
        }
    }

}
1、Oracle8/8i/9i数据库（thin模式） 

Class.forName('oracle.jdbc.driver.OracleDriver').newInstance(); 
String url='jdbc:oracle:thin:@localhost:1521:orcl'; //orcl为数据库的SID 
String user='test'; 
String password='test'; 
Connection conn= DriverManager.getConnection(url,user,password);  

　　2、DB2数据库 

Class.forName('com.ibm.db2.jdbc.app.DB2Driver ').newInstance(); 
String url='jdbc:db2://localhost:5000/sample'; //sample为你的数据库名 
String user='admin'; 
String password=''; 
Connection conn= DriverManager.getConnection(url,user,password);  

　　3、Sql Server7.0/2000数据库 

Class.forName('com.microsoft.jdbc.sqlserver.SQLServerDriver').newInstance(); 
String url='jdbc:microsoft:sqlserver://localhost:1433;DatabaseName=mydb'; 
//mydb为数据库 
String user='sa'; 
String password=''; 
Connection conn= DriverManager.getConnection(url,user,password);  

　　4、Sybase数据库 

Class.forName('com.sybase.jdbc.SybDriver').newInstance(); 
String url =' jdbc:sybase:Tds:localhost:5007/myDB';//myDB为你的数据库名 
Properties sysProps = System.getProperties(); 
SysProps.put('user','userid'); 
SysProps.put('password','user_password'); 
Connection conn= DriverManager.getConnection(url, SysProps);  

　　5、Informix数据库 

Class.forName('com.informix.jdbc.IfxDriver').newInstance(); 
String url = 'jdbc:informix-sqli://123.45.67.89:1533/myDB:INFORMIXSERVER=myserver; 
user=testuser;password=testpassword'; //myDB为数据库名 
Connection conn= DriverManager.getConnection(url);  

　　6、MySQL数据库 

Class.forName('org.gjt.mm.mysql.Driver').newInstance(); //或者Class.forName('com.mysql.jdbc.Driver');
String url ='jdbc:mysql://localhost/myDB?user=soft&password=soft1234&useUnicode=true&characterEncoding=8859_1' 
//myDB为数据库名 
Connection conn= DriverManager.getConnection(url);  

　　7、PostgreSQL数据库 

Class.forName('org.postgresql.Driver').newInstance(); 
String url ='jdbc:postgresql://localhost/myDB' //myDB为数据库名 
String user='myuser'; 
String password='mypassword'; 
Connection conn= DriverManager.getConnection(url,user,password);  

　　8、access数据库直连用ODBC的

Class.forName('sun.jdbc.odbc.JdbcOdbcDriver') ;
String url='jdbc:odbc:Driver={MicroSoft Access Driver (*.mdb)};DBQ='+application.getRealPath('/Data/ReportDemo.mdb');
Connection conn = DriverManager.getConnection(url,'','');
Statement stmtNew=conn.createStatement() ;