shiro学习笔记 过滤器 shiro 表单 验证码 登录

自己自定义实现了一个验证码表单过滤器,基于FormAuthenticationFilter

代码如下:

package cn.ddsxy.ddlx.shiro;
 
import cn.ddsxy.ddlx.util.CaptchaUtil;
import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.IncorrectCredentialsException;
import org.apache.shiro.authc.UnknownAccountException;
import org.apache.shiro.subject.Subject;
import org.apache.shiro.web.filter.authc.FormAuthenticationFilter;
import org.apache.shiro.web.util.WebUtils;
 
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
 
/**
 * 自定义表单过滤器
 * @author zhiguang
 */
public class CaptchaFormAuthentcationFileter extends FormAuthenticationFilter {
 
    /**
     * 是否开启验证码支持
     */
    private boolean captchaEbabled = true;
 
    /**
     * 验证码参数名
     */
    private String captchaParam = "captcha";
 
    public boolean isCaptchaEbabled() {
        return captchaEbabled;
    }
 
    public void setCaptchaEbabled(boolean captchaEbabled) {
        this.captchaEbabled = captchaEbabled;
    }
 
    public String getCaptchaParam() {
        return captchaParam;
    }
 
    public void setCaptchaParam(String captchaParam) {
        this.captchaParam = captchaParam;
    }
 
    public String getCaptcha(ServletRequest request){
        return WebUtils.getCleanParam(request, this.getCaptchaParam());
    }
 
    @Override
    protected CaptchaUserNamePassWordToken createToken(ServletRequest request, ServletResponse response) {
        String username = request.getParameter("username");
        String password = request.getParameter("password");
        String captcha = request.getParameter("captcha");
        return new CaptchaUserNamePassWordToken(username, password==null?"":password, captcha);
    }
 
    @Override
    protected boolean executeLogin(ServletRequest request, ServletResponse response) throws Exception {
        CaptchaUserNamePassWordToken token = createToken(request, response);
        try {
            if(captchaEbabled) CaptchaUtil.verify(request);
            Subject subject = getSubject(request, response);
            subject.login(token);
            return onLoginSuccess(token, subject, request, response);
        } catch (IncorrectCaptchaException e) {
            return onLoginFailure(token, e, request, response);
        } catch (UnknownAccountException e1) { // 不存在用户名对应的有效用户记录
            return onLoginFailure(token, e1, request, response);
        } catch (IncorrectCredentialsException e2) { // 用户名或密码不对
            return onLoginFailure(token, e2, request, response);
        } catch (AuthenticationException e3) { // 其它异常
            return onLoginFailure(token, e3, request, response);
        }
    }
 
    @Override
    protected void setFailureAttribute(ServletRequest request, AuthenticationException e) {
        if(e instanceof IncorrectCaptchaException){
            request.setAttribute(DEFAULT_ERROR_KEY_ATTRIBUTE_NAME,"验证码错误");
        }else if(e instanceof UnknownAccountException){
            request.setAttribute(DEFAULT_ERROR_KEY_ATTRIBUTE_NAME,"用户不存在");
        }else if(e instanceof IncorrectCredentialsException){
            request.setAttribute(DEFAULT_ERROR_KEY_ATTRIBUTE_NAME,"密码错误");
        }else if(e instanceof AuthenticationException){
            request.setAttribute(DEFAULT_ERROR_KEY_ATTRIBUTE_NAME,"登录失败");
        }
    }
 
    /**
     * 表示访问拒绝时是否自己处理，如果返回true表示自己不处理且继续拦截器链执行，返回false表示自己已经处理了（比如重定向到另一个页面）
     * @param request
     * @param response
     * @return
     * @throws Exception
     */
    @Override
    protected boolean onAccessDenied(ServletRequest request, ServletResponse response) throws Exception {
        return super.onAccessDenied(request, response);
    }
 
    /**
     * 是否允许访问，返回true表示允许
     * @param request
     * @param response
     * @param mappedValue
     * @return
     */
    @Override
    protected boolean isAccessAllowed(ServletRequest request, ServletResponse response, Object mappedValue) {
        return super.isAccessAllowed(request, response, mappedValue);
    }
}

CaptchaUtil.verify该方法验证验证码是否正确,可自行实现,重要的是executeLogin这个方法,我开始了解shiro的时候一直分不清这个FormAuthenticationFilter过滤器和Realm的doGetAuthenticationInfo(身份认证)有什么关系,看源码,看到了AuthenticatingFilter这个父类executeLogin方法里调用了

protected boolean executeLogin(ServletRequest request, ServletResponse response) throws Exception {
        AuthenticationToken token = this.createToken(request, response);
        if (token == null) {
            String msg = "createToken method implementation returned null. A valid non-null AuthenticationToken must be created in order to execute a login attempt.";
            throw new IllegalStateException(msg);
        } else {
            try {
                Subject subject = this.getSubject(request, response);
                subject.login(token);
                return this.onLoginSuccess(token, subject, request, response);
            } catch (AuthenticationException var5) {
                return this.onLoginFailure(token, var5, request, response);
            }
        }
    }