1、创建CustomRealm类

package com.zjc.shiro.realm;

import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.AuthenticationInfo;
import org.apache.shiro.authc.AuthenticationToken;
import org.apache.shiro.authc.SimpleAuthenticationInfo;
import org.apache.shiro.authz.AuthorizationInfo;
import org.apache.shiro.authz.SimpleAuthorizationInfo;
import org.apache.shiro.realm.AuthorizingRealm;
import org.apache.shiro.subject.PrincipalCollection;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

public class CustomRealm extends AuthorizingRealm {

    Map<String,String> userMap = new HashMap<>();

    {
        userMap.put("zjc","123456");
        super.setName("customRealm");
    }

    /**
     * 自定义授权过程
     * @param principals
     * @return
     */
    @Override
    protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principals) {
        String userName = (String) principals.getPrimaryPrincipal();

        //从数据或者缓存中获取角色数据
        Set<String> roles = getRolesByUserName(userName);

        //从数据或者缓存中获取权限数据
        Set<String> permissions = getPermissionsByUserName(userName);


        SimpleAuthorizationInfo simpleAuthorizationInfo = new SimpleAuthorizationInfo();

        simpleAuthorizationInfo.setStringPermissions(permissions);
        simpleAuthorizationInfo.setRoles(roles);
        return simpleAuthorizationInfo;


    }

    private Set<String> getPermissionsByUserName(String userName) {
        Set<String> sets = new HashSet<>();
        sets.add("user:delete");
        sets.add("user:add");
        return  sets;

    }

    private Set<String> getRolesByUserName(String userName) {
        Set<String> sets = new HashSet<>();
        sets.add("admin");
        sets.add("user");
        return  sets;

    }

    /**
     * 自定义认证的过程
     * @param token
     * @return
     * @throws AuthenticationException
     */
    @Override
    protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken token) throws AuthenticationException {

        //1、从主体传过来的认证信息中，获得用户名
        String userName = (String) token.getPrincipal();

        //2、通过用户名到数据库中获取凭证
        String password = getPasswordByUserName(userName);

        if (password == null){
            return null;
        }

        SimpleAuthenticationInfo authenticationInfo = new SimpleAuthenticationInfo("zjc",password,"customRealm");

        return authenticationInfo;
    }

    /**
     * 模拟数据库查询凭证
     * @param userName
     * @return
     */
    private String getPasswordByUserName(String userName) {
        return userMap.get(userName);
    }

}

2、 创建CustomRealmTest类

package com.zjc.test;

import com.zjc.shiro.realm.CustomRealm;
import org.apache.shiro.SecurityUtils;
import org.apache.shiro.authc.UsernamePasswordToken;
import org.apache.shiro.mgt.DefaultSecurityManager;
import org.apache.shiro.subject.Subject;
import org.junit.Test;

public class CustomRealmTest {

    @Test
    public void customRealmTest(){

        CustomRealm customRealm = new CustomRealm();

        DefaultSecurityManager manager = new DefaultSecurityManager();

        manager.setRealm(customRealm);

        SecurityUtils.setSecurityManager(manager);

        Subject subject = SecurityUtils.getSubject();

        UsernamePasswordToken token = new UsernamePasswordToken("zjc","123456");

        subject.login(token);

        System.out.println("isAuthenticated:"+subject.isAuthenticated());

        subject.checkRole("admin");

        subject.checkPermission("user:delete");
    }
}