代码语言：javascript复制
package com.shy;import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
publicclass ProcessServlet extends HttpServlet { protectedvoid Process(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("utf-8"); response.setContentType("text/html;charset=UTF-8"); String username = request.getParameter("username"); String password = request.getParameter("password"); boolean flag =true;
//将出借的信息写入 errorList中
List<String> errorList =new ArrayList<String>();
//判断用户名不能为空
if(null==username ||"".equals(username)) { errorList.add("用户名不能为空"); }
//判断用户不用小于4位
elseif(username.length()<4) { errorList.add("用户名不能小于4位"); }
//判断用户名第一位不能为数字
elseif(Character.isDigit(username.charAt(0))) { errorList.add("用户名首字母不能为数字"); }
//判断用户名只能为字母数字以及(.) 英文逗点
"for(int i=0;i<username.length();i )
{ char c = username.charAt(i);
if((c>='a'&&c<='z')||(c>='A'&&c<='Z')||(Character.isDigit(c))||(c=='.'))
{ continue; }
else { errorList.add("用户名只能为字母数字以及(.) 英文逗点"); } }
//判断密码不能小于6位
if(password.length() <6) { errorList.add("密码长度不能小于6位"); }
//判断密码不能由全部重复的字符组成
for(int j=0;j<password.length()-1;j )
{ if(password.charAt(j)!=password.charAt(j 1))
{ continue; }
else { errorList.add("密码不能由全部重复字符组成"); } }
//判断密码是不是全由数字组成
for(int i=0;i<password.length();i )
{ char c = password.charAt(i);
if(Character.isDigit(c)) { continue; }
else { flag=false; } }
//如果密码全由数字组成,判断他是否为连续字符
if(flag) { for(int k=0;k<password.length()-1;k )
{ if((int)password.charAt(k) 1!= (int)password.charAt(k 1))
{ continue; }
else { errorList.add("不能由连续的数字组成(123456)"); } } }
//如果密码全由数字组成,判断他是否为连续字符
if(flag) { for(int k=0;k< password.length()-1;k )
{ if((int)password.charAt(k)-1!= (int)password.charAt(k 1)) { continue; }
else { errorList.add("不能由连续的数字组成(123456)"); } } }
if(errorList.isEmpty())
{ request.setAttribute("username", username);
request.setAttribute("password", password);
request.getRequestDispatcher("javaservletsuccess.jsp").forward(request,response); }
else {
request.setAttribute("error", errorList);
request.getRequestDispatcher("javaservleterror.jsp").forward(request,response); } }
@Override
protectedvoid doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { Process(req,resp); }
@Override
protectedvoid doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { Process(req,resp); } }利用Servlet对用户名和密码进行服务器端验证
校验规则:
1. 用户名只能为数字/字母/英文点号(.), 且不能由数字开始, 至少4位
2. 密码不能由全部重复的字符组成, 不能由连续的数字组成(123456/654321), 至少6位
代码如下:
代码语言：javascript复制package com.shy;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
publicclass ProcessServlet extends HttpServlet {
protectedvoid Process(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
response.setContentType("text/html;charset=UTF-8");
String username = request.getParameter("username");
String password = request.getParameter("password");
boolean flag =true;
//将出借的信息写入 errorList中
List<String> errorList =new ArrayList<String>();
//判断用户名不能为空
if(null==username ||"".equals(username))
{
errorList.add("用户名不能为空");
}
//判断用户不用小于4位
elseif(username.length()<4)
{
errorList.add("用户名不能小于4位");
}
//判断用户名第一位不能为数字
elseif(Character.isDigit(username.charAt(0)))
{
errorList.add("用户名首字母不能为数字");
}
//判断用户名只能为字母数字以及(.) 英文逗点"
for(int i=0;i<username.length();i )
{
char c = username.charAt(i);
if((c>='a'&&c<='z')||(c>='A'&&c<='Z')||(Character.isDigit(c))||(c=='.'))
{
continue;
}
else
{
errorList.add("用户名只能为字母数字以及(.) 英文逗点");
}
}
//判断密码不能小于6位
if(password.length() <6)
{
errorList.add("密码长度不能小于6位");
}
//判断密码不能由全部重复的字符组成
for(int j=0;j<password.length()-1;j )
{
if(password.charAt(j)!=password.charAt(j 1))
{
continue;
}
else
{
errorList.add("密码不能由全部重复字符组成");
}
}
//判断密码是不是全由数字组成
for(int i=0;i<password.length();i )
{
char c = password.charAt(i);
if(Character.isDigit(c))
{
continue;
}
else
{
flag=false;
}
}
//如果密码全由数字组成,判断他是否为连续字符
if(flag)
{
for(int k=0;k<password.length()-1;k )
{
if((int)password.charAt(k) 1!= (int)password.charAt(k 1))
{
continue;
}
else
{
errorList.add("不能由连续的数字组成(123456)");
}
}
}
//如果密码全由数字组成,判断他是否为连续字符
if(flag)
{
for(int k=0;k< password.length()-1;k )
{
if((int)password.charAt(k)-1!= (int)password.charAt(k 1))
{
continue;
}
else
{
errorList.add("不能由连续的数字组成(123456)");
}
}
}
if(errorList.isEmpty())
{
request.setAttribute("username", username);
request.setAttribute("password", password);
request.getRequestDispatcher("javaservletsuccess.jsp").forward(request,response);
}
else
{
request.setAttribute("error", errorList);
request.getRequestDispatcher("javaservleterror.jsp").forward(request,response);
}
}
@Override
protectedvoid doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
Process(req,resp);
}
@Override
protectedvoid doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
Process(req,resp);
}
}
