Mybatis拦截器实现SAAS平台（动态修改SQL）随笔

我不是女神ヾ 2022-03-15 08:28 366阅读 0赞

首先，自定义拦截器

import com.swzx.risktech.model.User;
    import org.apache.ibatis.executor.statement.StatementHandler;
    import org.apache.ibatis.mapping.BoundSql;
    import org.apache.ibatis.plugin.*;
    import org.springframework.stereotype.Component;
    import org.springframework.web.context.request.RequestContextHolder;
    import org.springframework.web.context.request.ServletRequestAttributes;
    
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpSession;
    import java.lang.reflect.Field;
    import java.sql.Connection;
    import java.util.Properties;
    
    /**
     * author:cs  2019/02/28
     */
    
    //拦截StatementHandler类中参数类型为Statement的 prepare 方法
    //即拦截 Statement prepare(Connection var1, Integer var2) 方法
    @Component
    @Intercepts({@Signature(type = StatementHandler.class,method = "prepare",args = {Connection.class,Integer.class})})
    public class SqlInterceptor implements Interceptor {
        @Override
        public Object intercept(Invocation invocation) throws Throwable {
            StatementHandler statementHandler = (StatementHandler) invocation.getTarget();
            BoundSql boundSql = statementHandler.getBoundSql();
            HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
            HttpSession session=request.getSession();
            //获取到原始sql语句
            String sql = boundSql.getSql();
            String mSql = "";
            String strsql = sql.replace(" ","");
            User user = (User)session.getAttribute("loginUser");
            if(strsql.indexOf("cid=")==-1) {
                if (sql.indexOf("where")!=-1){
                    mSql = sql + " and cid="+user.getCid();
                }else{
                    mSql = sql + " where and cid="+user.getCid();
                }
            }
            //通过反射修改sql语句
            Field field = boundSql.getClass().getDeclaredField("sql");
            field.setAccessible(true);
            field.set(boundSql, mSql);
            return invocation.proceed();
        }
    
        @Override
        public Object plugin(Object target) {
            return Plugin.wrap(target,this);
        }
    
        @Override
        public void setProperties(Properties properties) {
            //此处可以接收到配置文件的property参数
        }
    }

然后就没有然后了，就是这么简单。