📄 adminchecker.java
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/***************************
*管理员登录时验证其合法性
*
*该类实例由静态厂类函数提供,该对象只能实例化一次
*
*在多线程的代码中使用该类的实例,必须把调用方法修饰为synchronized
******************************/
package mylib;
public class AdminChecker {
private AdminChecker() {
}
public static AdminChecker getInstance() {
return lc;
}
synchronized public void check(String name,String password) {
this.adminName = name;
this.password = password;
try {
ConnectionDB cdb = new ConnectionDB();
String sqlstr = "SELECT admin_name FROM tb_Administrators where admin_name = \'"+
adminName+"\' and admin_password = \'"+password+"\'";
java.sql.ResultSet rs = cdb.executeQuery(sqlstr);
if(rs.next()) {
System.out.println("通过验证!");
}
else {
System.out.println("用户名或密码错误!");
}
cdb.close();
}
catch(Exception ex) {
System.out.println("***AdminChecker.check(){}中异常***");
System.out.println("*********************************");
ex.printStackTrace();
System.out.println("*********************************");
}
}
private String adminName = null;
private String password = null;
private static AdminChecker lc = new AdminChecker();
/*********************************
*用于测试的main()
*********************************/
public static void main(String[] args) {
String userName = "区毅坚";
String password = "123456";
AdminChecker lc = AdminChecker.getInstance();
lc.check(userName,password);
}
}
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