struts-config.xml <form-bean name="checkForm" type="org.apache.struts.validator.DynaValidatorForm"> <form-property name="rand" type="java.lang.String" /> </form-bean> <action attribute="checkForm" input="/check/check.jsp" name="checkForm" path="/check" scope="request" validate="true" type="com.yourcompany.struts.action.CheckAction"> <forward name="ok" path="/check/checkok.jsp" /> </action>validation.xml <form name="checkForm"> <field property="rand" depends="required"> <arg key="checkForm.rand"/> </field> </form> spring config <bean name="/check" class="com.yourcompany.struts.action.CheckAction"/> checkAction.java public class CheckAction extends Action { /* * Generated Methods */
/** * Method execute * @param mapping * @param form * @param request * @param response * @return ActionForward */ public ActionForward execute(ActionMapping mapping, ActionForm form, HttpServletRequest request, HttpServletResponse response) { DynaValidatorForm checkForm = (DynaValidatorForm) form;// TODO Auto-generated method stub /*HttpSession session=request.getSession(); String strrand = (String)session.getAttribute("rand"); session.setAttribute("rand", strrand);*/ return mapping.findForward("ok"); } }check.jsp
<%@ page language="java" pageEncoding="ISO-8859-1"%> <%@ taglib uri="http://jakarta.apache.org/struts/tags-bean" prefix="bean"%> <%@ taglib uri="http://jakarta.apache.org/struts/tags-html" prefix="html"%> <html> <head> <title>JSP for DynaValidatorForm form</title> <meta http-equiv="Content-Type" content="text/html; charset=gb2312"> <META HTTP-EQUIV="Pragma" CONTENT="no-cache"> <META HTTP-EQUIV="Cache-Control" CONTENT="no-cache"> <META HTTP-EQUIV="Expires" CONTENT="0"> </head> <body> <html:form action="/check"> <td><img border=0 src="check/image.jsp"></td> <html:text property="rand"/><html:errors property="rand"/><br/> <html:submit/><html:cancel/> </html:form> </body> </html>
checkok.jsp
<%@ page language="java" import="java.util.*" pageEncoding="ISO-8859-1"%> <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <% String rand = (String)session.getAttribute("rand"); String input = request.getParameter("rand"); if (rand.equals(input)) { %> <font color=green>OK</font> <% } else { %> <font color=red>FAIL</font> <% } %> </body> </html>image.jsp
<%@ page language="java" import="java.util.*" %> <%@ page contentType="image/jpeg" import="java.awt.*,java.awt.image.*,javax.imageio.*" %> <%@ page import="java.io.OutputStream" %> <%! Color getRandColor(int fc,int bc){ Random random = new Random(); if(fc>255) fc=255; if(bc>255) bc=255; int r=fc+random.nextInt(bc-fc); int g=fc+random.nextInt(bc-fc); int b=fc+random.nextInt(bc-fc); return new Color(r,g,b); } %> <% response.setHeader("Pragma","No-cache"); response.setHeader("Cache-Control","no-cache"); response.setDateHeader("Expires", 0);
int width=60, height=20; BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); OutputStream os=response.getOutputStream(); Graphics g = image.getGraphics();
Random random = new Random();
g.setColor(getRandColor(200,250)); g.fillRect(0, 0, width, height);
g.setFont(new Font("Times New Roman",Font.PLAIN,18));
g.setColor(getRandColor(160,200)); for (int i=0;i<155;i++) { int x = random.nextInt(width); int y = random.nextInt(height); int xl = random.nextInt(12); int yl = random.nextInt(12); g.drawLine(x,y,x+xl,y+yl); }
String sRand=""; for (int i=0;i<4;i++){ String rand=String.valueOf(random.nextInt(10)); sRand+=rand;
g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110))); g.drawString(rand,13*i+6,16); }
session.setAttribute("rand",sRand);
g.dispose();
ImageIO.write(image, "JPEG",os); os.flush(); os.close(); os=null; response.flushBuffer(); out.clear(); out = pageContext.pushBody(); %>
