Java程序若何操作MySQL数据库_windows好用的数据恢复
日期:2014-07-13 / 人气: / 来源:网络
数据库内容:
java源代码:(代码实现的是查询成绩为100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 = "com.mysql.jdbc.Driver";
// DataSource 数据源名称DSN
private String DatabaseConnStr = "jdbc:mysql://localhost:3306/people_manage?useUnicode=true&characterEncoding=utf8"
",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
}
}
rs = null;
try {
conn = DriverManager
.getConnection(
"jdbc:mysql://localhost:3306/people_manage?useUnicode=true&characterEncoding=utf8",
"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 = 0;
try {
conn = DriverManager
.getConnection(
"jdbc:mysql://localhost:3306/people_manage?useUnicode=true&characterEncoding=utf8",
"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 = uid;
this.name = name;
this.banji = banji;
}
public people(String uid, String name, String banji, int score) {
this.uid = uid;
this.name = name;
this.banji = banji;
this.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_array1;// 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 sql2 = "insert people (uid,name) values ('uid001','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
"'";
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=null;
String uid_new, name, banji;
uid_new = null;
name = null;
banji = null;
String 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, banji;
uid_new = null;
name = null;
banji = null;
int score_new = 0;
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 = 0;
ResultSet rs_new = rs;
while (rs_new.next()) {// 统计结果集中学生个数
num ;
}
// System.out.println(num);
people_array1 = new people[num];
int i = 0;
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_array1[i] = new people(uid_new, name, banji, score_new);
i ;
}
} catch (Exception e) {
e.getMessage();
}
return people_array1;
}
public static void main(String args[]) {
/*
* people new_people=new people();
*
* manage mr=new manage(); //mr.add_people("000","小明");插入一个学生的信息
*
* new_people=mr.query_people("001");//查询uid=001的学生信息,返回对象 System.out.
* println("" new_people.getName() " " new_people.getBanji());
* mr.update_people("004", "小王");更新一个学生的信息
*
* new_people=mr.query_people("004");//更新后查询
*
* System.out.println("" new_people.getName() " " new_people.getBanji(
* ));
*/
manage mr = new manage();
// mr.delete_people("001");删除uid=001的学生信息
people[] people_array;// 声明对象数组
people_array = mr.query_people_byscore(100);// 返回成绩为一百的学生类数组,后输出
int num = 0;
num = people_array.length;
for (int i = 0; i < num; i ) {
System.out.println(people_array[i].getUid() " "
people_array[i].getName() " "
people_array[i].getBanji() " "
people_array[i].getScore());
}
}
}
程序运行结果:
mac系统如何配置PHP+MySQL环境
由于最近需要布置mantis用来进行bug追踪,在此记录其过程。由于PHP apache环境在Mac OS上是自带的,所以不需要另处下安装包,只需要简单配置一下即可。首先打开终端输入命令:sudovim/etc/apache2/httpd.conf其中有一行是
MySQL教程
作者:管理员
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