jsp实现登陆操作（带验证码）

数据脚本在webcontent下

package henu.filter;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

public class EncodingFilter implements Filter{
private String env=null;
	@Override
	public void init（FilterConfig filterConfig） throws ServletException {
		// TODO Auto-generated method stub
		env=filterConfig.getInitParameter（“coding“）;
	}

	@Override
	public void doFilter（ServletRequest request 
			ServletResponse response FilterChain chain）
			throws IOException ServletException {
		// TODO Auto-generated method stub
		System.out.println（“前处理“）;
		if（env!=null&&!env.isEmpty（）） {
		
			request.setCh

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     文件         842  2018-11-06 10:12  LoginWithValidateCode\.classpath
     文件         921  2018-11-20 15:58  LoginWithValidateCode\.project
     文件         567  2018-11-06 10:12  LoginWithValidateCode\.settings\.jsdtscope
     文件         364  2018-11-06 10:12  LoginWithValidateCode\.settings\org.eclipse.jdt.core.prefs
     文件         515  2018-11-20 15:58  LoginWithValidateCode\.settings\org.eclipse.wst.common.component
     文件         345  2018-11-06 10:12  LoginWithValidateCode\.settings\org.eclipse.wst.common.project.facet.core.xml
     文件          49  2018-11-06 10:12  LoginWithValidateCode\.settings\org.eclipse.wst.jsdt.ui.superType.container
     文件           6  2018-11-06 10:12  LoginWithValidateCode\.settings\org.eclipse.wst.jsdt.ui.superType.name
     文件          39  2018-11-06 10:12  LoginWithValidateCode\WebContent\meta-INF\MANIFEST.MF
     文件       14615  2018-11-17 23:16  LoginWithValidateCode\WebContent\WEB-INF\lib\jspsmartuploadUTF-8.jar
     文件      972009  2018-10-28 17:19  LoginWithValidateCode\WebContent\WEB-INF\lib\mysql-connector-java-5.1.36-bin.jar
     文件        1042  2018-11-20 15:58  LoginWithValidateCode\WebContent\WEB-INF\web.xml
     文件        1046  2018-11-20 15:59  LoginWithValidateCode\WebContent\loginnew.jsp
     文件         223  2018-11-06 10:29  LoginWithValidateCode\WebContent\succ.jsp
     文件           0  2018-11-19 09:16  LoginWithValidateCode\WebContent\upload\1.txt
     文件        3556  2018-11-04 22:28  LoginWithValidateCode\WebContent\userdbme.sql
     文件        1255  2017-11-29 16:09  LoginWithValidateCode\WebContent\validate.jsp
     文件        1563  2018-11-20 15:56  LoginWithValidateCode\WebContent\validateMix.jsp
     文件        1622  2018-11-20 15:58  LoginWithValidateCode\build\classes\henu\filter\EncodingFilter.class
     文件        4240  2018-11-20 15:58  LoginWithValidateCode\build\classes\henu\svt\LoginServlet.class
     文件         946  2018-11-20 15:58  LoginWithValidateCode\build\classes\henu\util\DbCon.class
     文件        1007  2018-11-06 11:11  LoginWithValidateCode\src\henu\filter\EncodingFilter.java
     文件        2983  2018-11-20 15:54  LoginWithValidateCode\src\henu\svt\LoginServlet.java
     文件         571  2018-11-06 10:13  LoginWithValidateCode\src\henu\util\DbCon.java