JDBC连接Oracle数据库

JDBC连接数据库可分为以下5个步骤：

// 1.加载驱动
try {
Class.forName("oracle.jdbc.driver.OracleDriver");
} catch (ClassNotFoundException e) {
e.printStackTrace();
}
//2.创建数据库连接
String url = "jdbc:oracle:thin:@127.0.0.1:1521:orcl";
Connection conn = null;
Statement st = null;
ResultSet rs = null;
try {
conn = DriverManager.getConnection(url, "gsuser", "root");
st = conn.createStatement();
//3.执行语句
rs = st.executeQuery("select * from cusinfo");
//4.处理结果
while(rs.next()){
String cusNo = rs.getString("cusno");
System.out.println(cusNo);
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}finally{
//5.释放资源
try {
if(rs!=null){
rs.close();
}
if(st!=null){
st.close();
}
if(conn!=null){
conn.close();
}
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}