A: try...catch(...) {...} finally {}
B: 关闭ResultSet,Statement , Connection
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.Statement;
public class ExceptionDemo {
public static void main(String[] args) {
Connection conn = null ;
Statement st = null ;
try {
// 注册驱动
Class.forName("com.mysql.jdbc.Driver") ;
// 获取连接对象
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/mydb", "root", "1234") ;
// 获取执行sql的对象
st = conn.createStatement() ;
// 执行sql , 获取结果
String sql = "insert into user(uid , name , sal) values (1 , 'zhansgan' , 34.56)" ;
int count = st.executeUpdate(sql) ;
// 处理结果
System.out.println(count);
} catch (Exception e) {
e.printStackTrace() ;
} finally { // 释放资源
if(st != null) {
try {
st.close() ;
} catch (SQLException e) {
e.printStackTrace();
}
}
if(conn != null) {
try {
conn.close() ;
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
}
