java程序 *** 作MySQL数据库

java程序 *** 作MySQL数据库,第1张

数据库内容

  java源代码 (代码实现的是查询成绩为 的人员信息 至于其他功能的 代码中有注释) 注意 在eclipse里运行程序的时候 要工程里插入jar包 否则运行异常! import java sql *import java io *class database_manage {  public Connection conn = null public ResultSet rs = null private String DatabaseDriver = " mysql jdbc Driver" // DataSource 数据源名称DSN  private String DatabaseConnStr = "jdbc:mysql://localhost: /people_manage?useUnicode=true&characterEncoding=utf "  + " root root" public void setDatabaseDriver(String Driver) { this DatabaseDriver = Driver }  public String getDatabaseDriver() { return (this DatabaseDriver) }  public void setDatabaseConnStr(String ConnStr) { this DatabaseConnStr = ConnStr }  public String getDatabaseConnStr() { return (this DatabaseConnStr) }  public database_manage() {// 构造函数连接数据库 try {  Class forName(DatabaseDriver)} catch (java lang ClassNotFoundException e) {  System err println("加载驱动器有错误:" + e getMessage()) System out print("执行插入有错误:" + e getMessage())// 输出到客户端 }  }  public ResultSet query(String sql) {// 查询数据库 rs = nulltry {  conn = DriverManager   getConnection(  "jdbc:mysql://localhost: /people_manage?useUnicode=true&characterEncoding=utf "  "root" "root") Statement stmt = conn createStatement() rs = stmt executeQuery(sql)} catch (SQLException ex) {  System err println("执行查询有错误:" + ex getMessage()) System out print("执行查询有错误:" + ex getMessage())// 输出到客户端 }

return rs

 }  public int update_database(String sql) {// 更新或插入数据库 int num = try {  conn = DriverManager   getConnection(  "jdbc:mysql://localhost: /people_manage?useUnicode=true&characterEncoding=utf "  "root" "root") Statement stmt = conn createStatement() num = stmt executeUpdate(sql)} catch (SQLException ex) {  System err println("执行插入有错误:" + ex getMessage()) System out print("执行插入有错误:" + ex getMessage())// 输出到客户端 }  CloseDataBase()return num }  public void CloseDataBase() {// 关闭数据库 try {  conn close()} catch (Exception end) {  System err println("执行关闭Connection对象有错误 " + end getMessage()) System out print("执行执行关闭Connection对象有错误 有错误:" + end getMessage())// 输出到客户端 }  } } class people {  private String uid private String name private String banji private int score public people() {  }  public people(String uid String name String banji) { this uid = uidthis name = namethis banji = banji }  public people(String uid String name String banji int score) { this uid = uidthis name = namethis banji = banjithis score = score }  public String getUid() { return uid }  public void setUid(String uid) { this uid = uid }  public String getName() { return name }  public void setName(String name) { this name = name }  public String getBanji() { return banji }  public void setBanji(String banji) { this banji = banji }  public int getScore() { return score }  public void setScore(int score) { this score = score } } public class manage {  private people[] people_array // 对象数组  public void add_people(String uid String name) {  String sql = "insert people (uid name) values ( " + uid + " " + name + " )"// sql插入语句 // String sql = "insert people (uid name) values ( uid tom )" database_manage db_obj = new database_manage()db_obj update_database(sql) }  public void update_people(String uid String name) {  String sql = "update people set name= " + name + " where uid= " + uid + " "database_manage db_obj = new database_manage()db_obj update_database(sql) }  public void delete_people(String uid) {  String sql = "delete from people  where uid= " + uid + " " database_manage db_obj = new database_manage() db_obj update_database(sql) }  public people query_people(String uid) { database_manage db_obj = new database_manage()// String adminid=nullString uid_new name banjiuid_new = nullname = nullbanji = nullString sql_query = "select * from people where uid= " + uid + " " try {  ResultSet rs = db_obj query(sql_query) if (rs next()) { uid_new = rs getString("uid")name = rs getString("name")banji = rs getString("banji") } } catch (Exception e) {  e getMessage()} people new_people = new people(uid_new name banji)return new_people }  public people[] query_people_byscore(int score) { database_manage db_obj = new database_manage()String uid_new name banjiuid_new = nullname = nullbanji = nullint score_new =

String sql_query = "select * from people where score=" + score// sql查询语句

try {

ResultSet rs = db_obj query(sql_query)// 查询后 返回结果集

int num =

ResultSet rs_new = rs

while (rs_new next()) {// 统计结果集中学生个数

num++

}

// System out println(num)

people_array = new people[num]

int i =

rs beforeFirst()// 返回结果集的开始

while (rs next()) {

uid_new = rs getString("uid")

name = rs getString("name")

banji = rs getString("banji")

score_new = rs getInt("score")

people_array [i] = new people(uid_new name banji score_new)

i++

}

} catch (Exception e) {

e getMessage()

}

return people_array

}

public static void main(String args[]) {

/*

* people new_people=new people()

*

* manage mr=new manage()//mr add_people(" " "小明")插入一个学生的信息

*

* new_people=mr query_people(" ")//查询uid= 的学生信息 返回对象 System out

* println(""+new_people getName()+"  "+new_people getBanji())

* mr update_people(" " "小王")更新一个学生的信息

*

* new_people=mr query_people(" ")//更新后查询

*

* System out println(""+new_people getName()+"  "+new_people getBanji(

* ))

*/

manage mr = new manage()

// mr delete_people(" ")删除uid= 的学生信息

people[] people_array// 声明对象数组

people_array = mr query_people_byscore( )// 返回成绩为一百的学生类数组 后输出

int num =

num = people_array length

for (int i = i <numi++) {

System out println(people_array[i] getUid() + " "

+ people_array[i] getName() + "  "

+ people_array[i] getBanji() + "  "

+ people_array[i] getScore())

}

}

}

lishixinzhi/Article/program/Java/JSP/201311/20030

安装配置MySQL

1.首先打开运行mysql-5.5.29-winx64.msi(就是上面的MySQL V5.5),你会进入到安装界面:

2.接下来。。。next->next。。。一直点击next,当你看到这样的界面:

这个是选择MySQL的安装目录。我的习惯是开发工具一般都选择默认的路径。当然你想使用其他路径也行,不过还是要提醒一点,路径不要包含中文。

继续next。

这个是MySQL服务的端口号,我们最好不要修改,不过要记住这个值3306。

然后next。。。欢迎你来到坑前!(我没让你踩呢,不急)

这个界面是设置我们MySQL系统的字符集。默认是让我们选择字符集”Latin1”,我就问你你知道这个是什么字符集吗。。。那你不要怪我孤陋寡闻,我第一次就是直接默认过去,最后发现,我的数据库不能使用中文!会出现乱码。然后也是折腾了好久才解决。

我们何不一开始就把问题解决呢对吧。这里我们选择第三项,然后选择字符集”gbk”,这个不用解释了吧。。。见下图:

继续next。看到设置管理员账号信息界面了吧:

选中第一个,然后输入密码(建议记性不好的同学使用密码”123456”。。。=。=)。设置好密码之后,你登陆MySQL的账号就是:

userName:root

password:***(你的密码)*

接下来嘛。。。等。。。wait。。。

不过相信我这个过程不会持续很久。Done:

3.接下来,检查下MySQL是否正确安装:

“我的电脑”->”管理”->”服务”。查看MySQL服务是否启动:

如果你发现你的MySQL尚未启动,可以在”运行”中使用”net start mysql”启动服务。然后在任务管理器中查看MySQL的运行状态:


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原文地址: http://outofmemory.cn/zaji/5908991.html

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