DBUtils工具类的运用

4378430 · 发表于 2018-1-16 00:27:17

本帖最后由 4378430 于 2018-1-16 00:29 编辑

package com.wangluo.demo;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import com.wangluo.jdbcutils.JDBCUtils;
import com.wwangluo.domain.Sort;
public class JDBCDemo {
public static void main(String[] args) throws SQLException {<div class="blockcode"><blockquote>package com.wangluo.jdbcutils;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class JDBCUtils {
private JDBCUtils() {
};
private static Connection con;
static {
try {
Class.forName("com.mysql.jdbc.Driver");
String url = "jdbc:mysql://localhost:3306/mybase";
String ursename = "root";
String password = "root";
con = DriverManager.getConnection(url, ursename, password);
} catch (Exception ex) {
throw new RuntimeException(ex + "数据库连接失败");
}
}
public static Connection getConnection() {
return con;
}
public static void close(Connection con, Statement sta, ResultSet rs) {
if (con != null) {
try {
con.close();
} catch (SQLException ex) {
}
}
if (sta != null) {
try {
sta.close();
} catch (SQLException ex) {
}
}
if (rs != null) {
try {
rs.close();
} catch (SQLException ex) {
}
}
}
public static void close(Connection con, Statement sta) {
if (con != null) {
try {
con.close();
} catch (SQLException ex) {
}
}
if (sta != null) {
try {
sta.close();
} catch (SQLException ex) {
}
}
}
}

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package com.wwangluo.domain;
public class Sort {
private int sid;
private String sname;
private double sprice;
private String sdesc;
public Sort() {
super();
// TODO Auto-generated constructor stub
}
public Sort(int sid, String sname, double sprice, String sdesc) {
super();
this.sid = sid;
this.sname = sname;
this.sprice = sprice;
this.sdesc = sdesc;
}
public int getSid() {
return sid;
}
public void setSid(int sid) {
this.sid = sid;
}
public String getSname() {
return sname;
}
public void setSname(String sname) {
this.sname = sname;
}
public double getSprice() {
return sprice;
}
public void setSprice(double sprice) {
this.sprice = sprice;
}
public String getSdesc() {
return sdesc;
}
public void setSdesc(String sdesc) {
this.sdesc = sdesc;
}
@Override
public String toString() {
return "Sort [sid=" + sid + ", sname=" + sname + ", sprice=" + sprice + ", sdesc=" + sdesc + "]";
}
}

复制代码

package com.wangluo.demo;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import com.wangluo.jdbcutils.JDBCUtils;
import com.wwangluo.domain.Sort;
public class JDBCDemo {
public static void main(String[] args) throws SQLException {
// 调用JDBC工具类直接获取数据库连接
Connection con = JDBCUtils.getConnection();
// 连接获取sql语句对象
PreparedStatement pst = con.prepareStatement("SELECT * FROM sort");
// 调用cha询方法获取结果集
ResultSet rs = pst.executeQuery();
// 创建集合对象
List<Sort> list = new ArrayList<Sort>();
// 获取的每个对象封装到Sort对象中
while (rs.next()) {
Sort s = new Sort(rs.getInt("sid"), rs.getString("sname"), rs.getDouble("sprice"), rs.getString("sdesc"));
list.add(s);
}
for (Sort s : list) {
System.out.println(s);
}
JDBCUtils.close(con, pst, rs);
}
}

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DBUtils提供了一些工具类:就是为了让我们对sql的操作更加方便

4378430 · 发表于 2018-3-8 16:41:52

年轻有梦发表于 2018-2-21 09:41
这是JDBC DBUtils是QueryRunner 汗~~~

标题弄错了汗~~~

青蓝梦 · 发表于 2018-2-21 09:41:27

这是JDBC DBUtils是QueryRunner 汗~~~

wsmwzd · 发表于 2018-2-18 23:44:12

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[android教程] DBUtils工具类的运用