比较笨的问题 本人新手 不好意思 关于jsp调用DAO层方法的 不需要框架,楼主也不能把这么多java代码写到jsp里。你写个util类,然后通过jsp调用util,返回的结果再显示到jsp 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 util 是DButil么? 我有这个包 我主要不知道具体代码应该怎么调用,package zt.util;import java.io.File;import java.io.FileInputStream;import java.io.IOException;import java.io.InputStream;import java.sql.Connection;import java.sql.DriverManager;import java.sql.PreparedStatement;import java.sql.SQLException;import java.sql.Statement;import java.util.Properties;public class DButil2 { private static String url="jdbc:mysql:///orderfoods"; private static String driver; private static String user="root"; private static String psw="root"; // 获得数据库连接 static { try { // mysql com.mysql.jdbc.Driver //Class.forName("com.mysql.jdbc.Driver"); DriverManager.registerDriver(new com.mysql.jdbc.Driver()); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } // DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver()); // // System.setProperty("jdbc.drivers", // "oracle.jdbc.driver.OracleDriver"); } public static Connection getConnection() { Connection conn = null; try { conn = DriverManager.getConnection(url, user, psw); } catch (SQLException e) { e.printStackTrace(); } return conn; } /** * * @param conn * @return Statement 语句对象,语句对象执行SQL */ public static Statement getStatement(Connection conn) { Statement stmt = null; try { stmt = conn.createStatement(); } catch (SQLException e) { e.printStackTrace(); } return stmt; } /** * * @param conn * @param sql * insert into t_user values (?,?,?) * @return PreparedStatement 预编译语句对象 性能较Statement好,解决SQL注入问题 */ public static PreparedStatement getPreparedStatement(Connection conn, String sql) { PreparedStatement pstmt = null; try { pstmt = conn.prepareStatement(sql); } catch (SQLException e) { e.printStackTrace(); } return pstmt; } public static void closeConnection(Connection conn) { if (conn != null) { try { if (!conn.isClosed()) { conn.close(); } } catch (SQLException e) { e.printStackTrace(); } } } public static void closeStatement(Statement stmt) { if (stmt != null) { try { stmt.close(); } catch (SQLException e) { e.printStackTrace(); } } } /* 读属性文件 */ private void readProperties(){ Properties pro = new Properties(); File file = null; InputStream in = null; try { file = new File("src/db.properties"); in = new FileInputStream(file); pro.load(in); if(pro != null){ url = pro.getProperty("url"); driver = pro.getProperty("driver"); user = pro.getProperty("user"); psw = pro.getProperty("psw"); } } catch (Exception e) { e.printStackTrace(); }finally{ try { in.close(); } catch (IOException e) { e.printStackTrace(); } } }// public static void main(String[] args) {// new DButil();// }}这是我的util 再写个类,调用你这个util,要把sql传进去,没看到你返回结果集的方法啊,请加q:779815835 问题已解决https://blog.csdn.net/yelongacui/article/details/88249830 求 一个js 效果 点击“显示更多”的时候在本页面 加载更多内容 关于javascript引用后台方法 ActiveX控件在我的IE里为什么不能运行? jquery的菜单效果? javascript 的一个问题 字符串转化问题。。 还有人吗?我有段代码请我解释一下。 xloadtree中怎么保留点击的焦点? 如何得到一个元素在网页上的精确位置?在线结贴! 请问怎样通过input的type类型查找控件并获得其value啊? 导入sql文件时候,navicat报错 将JSON对象转化为二维数组,哪些地方用到?
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;
public class DButil2 { private static String url="jdbc:mysql:///orderfoods";
private static String driver;
private static String user="root";
private static String psw="root";
// 获得数据库连接
static {
try {
// mysql com.mysql.jdbc.Driver
//Class.forName("com.mysql.jdbc.Driver");
DriverManager.registerDriver(new com.mysql.jdbc.Driver());
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} // DriverManager.registerDriver(new oracle.jdbc.driver.OracleDriver());
//
// System.setProperty("jdbc.drivers",
// "oracle.jdbc.driver.OracleDriver");
} public static Connection getConnection() {
Connection conn = null;
try {
conn = DriverManager.getConnection(url, user, psw);
} catch (SQLException e) {
e.printStackTrace();
}
return conn;
} /**
*
* @param conn
* @return Statement 语句对象,语句对象执行SQL
*/
public static Statement getStatement(Connection conn) {
Statement stmt = null;
try {
stmt = conn.createStatement();
} catch (SQLException e) {
e.printStackTrace();
}
return stmt;
} /**
*
* @param conn
* @param sql
* insert into t_user values (?,?,?)
* @return PreparedStatement 预编译语句对象 性能较Statement好,解决SQL注入问题
*/
public static PreparedStatement getPreparedStatement(Connection conn,
String sql) {
PreparedStatement pstmt = null;
try {
pstmt = conn.prepareStatement(sql);
} catch (SQLException e) {
e.printStackTrace();
}
return pstmt;
} public static void closeConnection(Connection conn) {
if (conn != null) {
try {
if (!conn.isClosed()) {
conn.close();
}
} catch (SQLException e) {
e.printStackTrace();
}
}
} public static void closeStatement(Statement stmt) {
if (stmt != null) {
try {
stmt.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
/* 读属性文件
*/
private void readProperties(){
Properties pro = new Properties();
File file = null;
InputStream in = null;
try {
file = new File("src/db.properties");
in = new FileInputStream(file);
pro.load(in);
if(pro != null){
url = pro.getProperty("url");
driver = pro.getProperty("driver");
user = pro.getProperty("user");
psw = pro.getProperty("psw");
}
} catch (Exception e) {
e.printStackTrace();
}finally{
try {
in.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
// public static void main(String[] args) {
// new DButil();
// }
}
这是我的util