JDBC简单范例

时间:2023-03-09 07:11:16
JDBC简单范例

连接工具类

import java.sql.Connection;
import java.sql.DriverManager; public class DBUtil {
// 建立连接方法
public static Connection open() {
try {
Class.forName("com.mysql.jdbc.Driver");
return DriverManager.getConnection(
"jdbc:mysql://localhost:3306/GeekDB", "root", "123456");
} catch (Exception e) {
e.printStackTrace();
}
return null;
} // 关闭连接方法
public static void close(Connection conn) {
if (conn != null) {
try {
conn.close();
} catch (Exception e) {
e.printStackTrace();
}
} } }

使用范例

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.Statement; public class Test { public static void main(String[] args) { Connection conn = null;
String sql = null;
Statement stmt = null;
PreparedStatement pstmt = null;
ResultSet rs = null; // Statement查询*
sql = "select * from customertbl";
conn = DBUtil.open();
try {
stmt = conn.createStatement();
rs = stmt.executeQuery(sql);
while (rs.next()) {
int id = rs.getInt(1);
String name = rs.getString(2);
String email = rs.getString(3);
System.out.println(id + " " + name + " " + email);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
DBUtil.close(conn);
System.out.println("-----DONE-----");
} // PreparedStatement插入一条
sql = "insert into customertbl (name, email) values (?, ?)";
conn = DBUtil.open();
try {
pstmt = conn.prepareStatement(sql);
pstmt.setString(1, "Amy");
pstmt.setString(2, "amy@163.com");
pstmt.executeUpdate();
} catch (Exception e) {
e.printStackTrace();
} finally {
DBUtil.close(conn);
System.out.println("-----DONE-----");
} }
}