Mysql数据库的连接：（这个例子我只是测试Connection是否为null，检测是否连接成功）

package JDBC;import java.sql.Connection;import java.sql.DriverManager;import java.sql.SQLException;public class search {    private static final String driver="com.mysql.jdbc.Driver";   private static final String url="jdbc:mysql://localhost:3306/"    +"json?useSSL=false&useUnicode=true&characterEncoding=utf-8";    private static final String user="root";    private static final String password="1234";    private static Connection conn=null;      static    {        try {            Class.forName(driver);   //注册驱动        } catch (ClassNotFoundException e) {            e.printStackTrace();        }    }     public static Connection getConnection()    {        try {            conn=DriverManager.getConnection(url, user, password); //建立连接            return conn;        } catch (SQLException e) {            e.printStackTrace();            return null;        }    }    public static void main(String [] args)    {        Connection conn=search.getConnection();        if(conn!=null)        {            System.out.println("连接数据库成功");        }else        {            System.out.println("连接数据库失败");        }    }}

 

Oracle数据连接：

package hello.ant; import java.sql.*; public class jdbc{ //设定一些参数String url="jdbc:oracle:thin:@127.0.0.1:1521:orcl"; String user="root"; String password="1234"; Connection conn=null; Statement s; ResultSet r=null; public jdbc(){ try{ Class.forName("oracle.jdbc.driver.OracleDriver").newInstance();  //注册驱动conn = DriverManager.getConnection(url,user,password);           //建立连接s=c.createStatement();                                           //创建Statement   }catch(Exception e){     e.printStackTrace();    } } public boolean executeUpdate(String sql){    //根据传进来的sql语句更新数据库的数据try { s.executeUpdate(sql); return true;    }catch (SQLException e)    {     e.printStackTrace();     return false;     } } public ResultSet executeQuery(String sql){    //根据传进来的sql语句查询数据库的数据，并返回结果集rtry { r=s.executeQuery(sql); }catch(SQLException e) {      e.printStackTrace();     } return r; } public void close() {                        //将结果集和statement关闭try {     r.close();     s.close(); }catch(Exception e) {      e.printStackTrace();     } } public static void main(String[] args){ ResultSet r;    jdbc j = new jdbc();   //实例化Model类   r=j.executeQuery("select * from test"); //调用查询的方法，并将sql语句传过去try{     while (r.next()){ //遍历结果集    System.out.println(r.getString("id"));     System.out.println(r.getString("name"));    //打印查询到的数据   } }catch(Exception e){     e.printStackTrace(); } } }