使用springboot，权限管理使用spring security，使用内存用户验证，但无响应报错：
java.lang.IllegalArgumentException: There is no PasswordEncoder mapped for the id "null"
解决方法：
spring security 5.X版本，此版本需要提供一个PasswordEncorder的实例,否则页面毫无响应。
PasswordEncorder的实现类。
 

package com.example.demo.security;

import org.springframework.security.crypto.password.PasswordEncoder;

/**
 *
 * spring security 5.X版本，此版本需要提供一个PasswordEncorder的实例
 * @author lf
 * @date 2019/6/6 - 17:31
 */
public class MyPasswordEncoder implements PasswordEncoder {
    @Override
    public String encode(CharSequence charSequence) {

        return charSequence.toString();
    }

    @Override
    public boolean matches(CharSequence charSequence, String s) {
        return s.equals(charSequence.toString());
    }
}

然后修改：Security配置类

package com.example.demo.security;

import org.springframework.context.annotation.Configuration;
import org.springframework.security.config.annotation.authentication.builders.AuthenticationManagerBuilder;
import org.springframework.security.config.annotation.web.builders.HttpSecurity;
import org.springframework.security.config.annotation.web.builders.WebSecurity;
import org.springframework.security.config.annotation.web.configuration.EnableWebSecurity;
import org.springframework.security.config.annotation.web.configuration.WebSecurityConfigurerAdapter;

/**
 * @author lf
 * @date 2019/6/6 - 13:49
 */
@Configuration
@EnableWebSecurity
public class WebSecurityConfig extends WebSecurityConfigurerAdapter {
    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http.formLogin()//启用默认登陆界面
                .failureForwardUrl("/login?error")
                //登录失败返回URL：/login?error
                .defaultSuccessUrl("/ayUser/test  ")
                //登录成功跳转URL：这里跳转到用户的首页
                .permitAll();//登录页面全部权限可访问
        super.configure(http);
       /* //设置登录,注销，表单登录不用拦截，其他请求要拦截
        http.authorizeRequests().antMatchers("/").permitAll()
                .anyRequest().authenticated()
                .and()
                .logout().permitAll()
                .and()
                .formLogin();
        //关闭默认的csrf认证
        http.csrf().disable();*/
    }

    @Override
    protected void configure(AuthenticationManagerBuilder auth) throws Exception {
//        super.configure(auth);
        auth.inMemoryAuthentication().passwordEncoder(new MyPasswordEncoder())
                .withUser("阿毅").password("123456").roles("ADMIN")
                .and()
                .withUser("阿兰").password("123456").roles("USER");
    }

    @Override
    public void configure(WebSecurity web) throws Exception {
//        super.configure(web);
        //设置静态资源不要拦截
        web.ignoring().antMatchers("/js/**", "/cs/**", "/images/**");

    }
}