/*
*Test's New Java Files
*链接数据库工具类
*@auther student
*/
//package com.web
import java.sql.*;public class DBUtil {
private static final String DRIVER = "com.mysql.jdbc.Driver";
//mydata:数据库名
//user:登录数据库的用户名
//password:登录数据库的密码
private static final String URL = "jdbc:mysql://localhost/mydata?user=root&password=sql";
/**
* 获得数据库连接的方法
* @return
*/
public static Connection getCon(){
Connection con = null;
try{
Class.forName(DRIVER);//加载驱动程序并注册
con = DriverManager.getConnection(URL);
//通过驱动程序获得数据局库连接对象
}catch(Exception ex){
ex.printStackTrace();
}
return con;
}
/**
* 关闭数据库的方法
* @param rs:记录集对象
* @param pstmt:预编译上下文对象
* @param con:连接对象
*/
public static void closeDB(ResultSet rs,PreparedStatement pstmt,Connection con)
{
if(rs != null){
try{
rs.close();
rs = null;
}catch(Exception ex){
ex.printStackTrace();
}
}
if(pstmt != null){
try{
pstmt.close();
pstmt = null;
}catch (Exception ex){
ex.printStackTrace();
}
}
if(con != null){
try{
con.close();
con = null;
}catch(Exception ex){
ex.printStackTrace();
}
}
}
}
/*
*@author student
*/
//package com.westaccp.mysql;
public class Student {
private int stuNo;
private String stuName;
private int stuAge;
private String stuBirthday;
public int getStuNo(){
return stuNo;
}
public void setStuNo(int stuNo){
this.stuNo = stuNo;
}
public String getStuName(){
return stuName;
}
public void setStuName(String stuName ){
this.stuName =stuName;
}
public int getStuAge(){
return stuAge;
}
public void setStuAge(int stuAge){
this.stuAge = stuAge;
}
public String getStuBirthday(){
return stuBirthday;
}
public void setStuBirthday(String stuBirthday){
this.stuBirthday = stuBirthday;
}
}
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;
/*
*数据库操作类
*@author student
*
*/
public class StudentDAO {
public List<Student> findALL(){
Connection con = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
List<Student> stuList = null;
try{
con = DBUtil.getCon();//通过连接类获得连接对象
String sql = "select * from student";//sql语句
pstmt = con.prepareStatement(sql);//通过连接对象获得预编译上下文对象
rs = pstmt.executeQuery();//执行查询,获得记录集
stuList = new ArrayList<Student>();
while(rs.next()){ //rs.next():让游标向下移动一行
//如果游标指向某条记录,返回true,否则返回false
Student stu = new Student();
stu.setStuNo(rs.getInt("stuNo"));
stu.setStuName(rs.getString("stuName"));
stu.setStuAge(rs.getInt("stuAge"));
stu.setStuBirthday(rs.getString("stuBirthday"));
stuList.add(stu);
}
}catch(Exception ex){
ex.printStackTrace();
}finally {
DBUtil.closeDB(rs, pstmt, con);
}
return stuList;
}
public Student findByNo(int stuNo){
Connection con = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
Student stu = null;
try {
con =DBUtil.getCon();//通过连接类获得连接对象
String sql = "select * from student where stuNo=?";//sql语句
pstmt = con.prepareStatement(sql);//通过连接对象获得预编译上下文对象
pstmt.setInt(1, stuNo);
rs = pstmt.executeQuery(); //执行查询,获得记录集
if(rs.next()){//如果可能返回多条记录,用while,如果最多返回一条记录,用if
stu.setStuNo(rs.getInt("stuNo"));
stu.setStuName(rs.getString("stuName"));
stu.setStuAge(rs.getInt("stuAge"));
stu.setStuBirthday(rs.getString("stuBirthday"));
}
} catch(Exception ex){
ex.printStackTrace();
} finally {
DBUtil.closeDB(rs, pstmt, con);
}
return stu;
}
public int deleteByNo(int stuNo) {
Connection con = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
int rowCount = 0;
try {
con =DBUtil.getCon();//通过连接类获得连接对象
String sql = "delete from student where stuNo =?" ;//SQL语句
pstmt = con.prepareStatement(sql);//通过连接对象获得预编译上下文对象
pstmt.setInt(1, stuNo);
rowCount = pstmt.executeUpdate();//执行更新
}catch (Exception ex) {
ex.printStackTrace();
}finally {
DBUtil.closeDB(rs, pstmt, con);
}
return rowCount;
}}import java.util.List;
public class TestJdbc { /**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
StudentDAO stuDao = new StudentDAO();
List<Student> stulist = stuDao.findALL();
for(Student stu : stuList){
System.out.println(stu.getStuNo() +"--"+stu.getStuName());
} }}[/code]
无法将这4个文件编译 他们的package不能统一,麻烦高手教下如何执行这4个文件。。
*Test's New Java Files
*链接数据库工具类
*@auther student
*/
//package com.web
import java.sql.*;public class DBUtil {
private static final String DRIVER = "com.mysql.jdbc.Driver";
//mydata:数据库名
//user:登录数据库的用户名
//password:登录数据库的密码
private static final String URL = "jdbc:mysql://localhost/mydata?user=root&password=sql";
/**
* 获得数据库连接的方法
* @return
*/
public static Connection getCon(){
Connection con = null;
try{
Class.forName(DRIVER);//加载驱动程序并注册
con = DriverManager.getConnection(URL);
//通过驱动程序获得数据局库连接对象
}catch(Exception ex){
ex.printStackTrace();
}
return con;
}
/**
* 关闭数据库的方法
* @param rs:记录集对象
* @param pstmt:预编译上下文对象
* @param con:连接对象
*/
public static void closeDB(ResultSet rs,PreparedStatement pstmt,Connection con)
{
if(rs != null){
try{
rs.close();
rs = null;
}catch(Exception ex){
ex.printStackTrace();
}
}
if(pstmt != null){
try{
pstmt.close();
pstmt = null;
}catch (Exception ex){
ex.printStackTrace();
}
}
if(con != null){
try{
con.close();
con = null;
}catch(Exception ex){
ex.printStackTrace();
}
}
}
}
/*
*@author student
*/
//package com.westaccp.mysql;
public class Student {
private int stuNo;
private String stuName;
private int stuAge;
private String stuBirthday;
public int getStuNo(){
return stuNo;
}
public void setStuNo(int stuNo){
this.stuNo = stuNo;
}
public String getStuName(){
return stuName;
}
public void setStuName(String stuName ){
this.stuName =stuName;
}
public int getStuAge(){
return stuAge;
}
public void setStuAge(int stuAge){
this.stuAge = stuAge;
}
public String getStuBirthday(){
return stuBirthday;
}
public void setStuBirthday(String stuBirthday){
this.stuBirthday = stuBirthday;
}
}
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;
/*
*数据库操作类
*@author student
*
*/
public class StudentDAO {
public List<Student> findALL(){
Connection con = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
List<Student> stuList = null;
try{
con = DBUtil.getCon();//通过连接类获得连接对象
String sql = "select * from student";//sql语句
pstmt = con.prepareStatement(sql);//通过连接对象获得预编译上下文对象
rs = pstmt.executeQuery();//执行查询,获得记录集
stuList = new ArrayList<Student>();
while(rs.next()){ //rs.next():让游标向下移动一行
//如果游标指向某条记录,返回true,否则返回false
Student stu = new Student();
stu.setStuNo(rs.getInt("stuNo"));
stu.setStuName(rs.getString("stuName"));
stu.setStuAge(rs.getInt("stuAge"));
stu.setStuBirthday(rs.getString("stuBirthday"));
stuList.add(stu);
}
}catch(Exception ex){
ex.printStackTrace();
}finally {
DBUtil.closeDB(rs, pstmt, con);
}
return stuList;
}
public Student findByNo(int stuNo){
Connection con = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
Student stu = null;
try {
con =DBUtil.getCon();//通过连接类获得连接对象
String sql = "select * from student where stuNo=?";//sql语句
pstmt = con.prepareStatement(sql);//通过连接对象获得预编译上下文对象
pstmt.setInt(1, stuNo);
rs = pstmt.executeQuery(); //执行查询,获得记录集
if(rs.next()){//如果可能返回多条记录,用while,如果最多返回一条记录,用if
stu.setStuNo(rs.getInt("stuNo"));
stu.setStuName(rs.getString("stuName"));
stu.setStuAge(rs.getInt("stuAge"));
stu.setStuBirthday(rs.getString("stuBirthday"));
}
} catch(Exception ex){
ex.printStackTrace();
} finally {
DBUtil.closeDB(rs, pstmt, con);
}
return stu;
}
public int deleteByNo(int stuNo) {
Connection con = null;
PreparedStatement pstmt = null;
ResultSet rs = null;
int rowCount = 0;
try {
con =DBUtil.getCon();//通过连接类获得连接对象
String sql = "delete from student where stuNo =?" ;//SQL语句
pstmt = con.prepareStatement(sql);//通过连接对象获得预编译上下文对象
pstmt.setInt(1, stuNo);
rowCount = pstmt.executeUpdate();//执行更新
}catch (Exception ex) {
ex.printStackTrace();
}finally {
DBUtil.closeDB(rs, pstmt, con);
}
return rowCount;
}}import java.util.List;
public class TestJdbc { /**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
StudentDAO stuDao = new StudentDAO();
List<Student> stulist = stuDao.findALL();
for(Student stu : stuList){
System.out.println(stu.getStuNo() +"--"+stu.getStuName());
} }}[/code]
无法将这4个文件编译 他们的package不能统一,麻烦高手教下如何执行这4个文件。。
解决方案 »
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