文档根元素 "beans" 必须匹配 DOCTYPE 根 "null"。

项目已经基本完工了，本是打算起来运行测试一番，然后就开始报各种错，前面的就先不说了 ，都很离奇，因为项目之前测试是好用的，不知为何。

定位的错误应该是发生在spring配置文件，最后这个错在网上找了好多的博客解决办法，但是都不行。（配置文件配好之后都没动过，之前也是正常运行的）
找了很多，最后我的解决办法是把这个spring文件删掉，重新写了一份，然后项目就起来了。。。。重新构建项目，不要用maven重新构建，自己也是刚接触maven不太懂，但是自己的感觉maven重新构建会出一些问题（个人看法），然后我试着用这个，如图：

在附一下之前的配置文件：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:redis="http://www.springframework.org/schema/redis"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
                           http://www.springframework.org/schema/beans/spring-beans.xsd
                           http://www.springframework.org/schema/aop
                           http://www.springframework.org/schema/aop/spring-aop.xsd
                           http://www.springframework.org/schema/redis
                           http://www.springframework.org/schema/redis/spring-redis-1.0.xsd
                           http://www.springframework.org/schema/tx
                           http://www.springframework.org/schema/tx/spring-tx.xsd
                           http://www.springframework.org/schema/context
                           http://www.springframework.org/schema/context/spring-context.xsd">

    <!--注解开发  扫描包产生对象-->
    <context:component-scan base-package="com.shop"/>
    <!--加载连接池属性文件-->
    <context:property-placeholder location="classpath:db.properties"/>

    <context:property-placeholder
            location="classpath:redis.properties" file-encoding="UTF-8"
            ignore-unresolvable="true" ignore-resource-not-found="true" order="2"
            system-properties-mode="NEVER" />

    <!--配置c3p0连接池-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${db.driver}"/>
        <property name="jdbcUrl" value="${db.url}"/>
        <property name="user" value="${db.username}"/>
        <property name="password" value="${db.password}"/>
        <property name="maxPoolSize" value="${c3p0.maxPoolSize}"/>
        <property name="minPoolSize" value="${c3p0.minPoolSize}"/>
        <property name="autoCommitOnClose" value="${c3p0.autoCommitOnClose}"/>
        <property name="checkoutTimeout" value="${c3p0.checkoutTimeout}"/>
        <property name="acquireRetryAttempts" value="${c3p0.acquireRetryAttempts}"/>
    </bean>

    <!--配置sqlsessionFactory 产生sqlsession对象-->
    <bean id="factoryBean" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource" />
        <property name="typeAliasesPackage" value="com.shop.pojo"/>
        <!-- 扫描sql配置文件:mapper需要的xml文件 -->
        <property name="mapperLocations" value="classpath:applicationContext.xml"/>
        <property name="configLocation" value="classpath:sqlMapConfig.xml"/>
    </bean>

    <bean id="keySerializer"
          class="org.springframework.data.redis.serializer.StringRedisSerializer"/>
    <bean id="valueSerializer"
          class="org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer"/>
    <bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig">
        <property name="maxTotal" value="200"/>
        <property name="maxIdle" value="50"/>
        <property name="minIdle" value="8"/>
        <property name="maxWaitMillis" value="5000"/>
        <property name="numTestsPerEvictionRun" value="10"/>
        <property name="testOnBorrow" value="true"/>
        <property name="testOnReturn" value="true"/>
        <property name="testWhileIdle" value="true"/>
        <property name="timeBetweenEvictionRunsMillis" value="30000"/>
        <property name="minEvictableIdleTimeMillis" value="60000"/>
    </bean>
    <bean id="jedisConnectionFactory"
          class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory">
        <property name="poolConfig" ref="jedisPoolConfig"/>
        <property name="hostName" value="localhost" />
        <property name="port" value="6379"/>
        <property name="password" value=""/>
        <property name="database" value="11"/>
        <property name="timeout" value="1800"/>
        <property name="usePool" value="true"/>
    </bean>
    <!-- redis template definition -->
    <bean id="redisTemplate" class="org.springframework.data.redis.core.StringRedisTemplate">
        <property name="connectionFactory" ref="jedisConnectionFactory"/>
        <property name="keySerializer" ref="keySerializer"/>
        <property name="valueSerializer" ref="valueSerializer"/>
        <property name="hashKeySerializer" ref="keySerializer"/>
        <property name="hashValueSerializer" ref="valueSerializer"/>
        <property name="enableTransactionSupport" value="false"/>
    </bean>
    <bean id="redisTemplateTransactional" class="org.springframework.data.redis.core.StringRedisTemplate">
        <property name="connectionFactory" ref="jedisConnectionFactory"/>
        <property name="keySerializer" ref="keySerializer"/>
        <property name="valueSerializer" ref="valueSerializer"/>
        <property name="hashKeySerializer" ref="keySerializer"/>
        <property name="hashValueSerializer" ref="valueSerializer"/>
        <property name="enableTransactionSupport" value="true"/>
    </bean>
    <!--<bean id="redisHttpSessionConfiguration"
          class="org.springframework.session.data.redis.config.annotation.web.http.RedisHttpSessionConfiguration">
        <property name="maxInactiveIntervalInSeconds" value="1800"/>
        <property name="cookieSerializer" ref="defaultCookieSerializer"/>
    </bean>
    <bean id="defaultCookieSerializer"
          class="org.springframework.session.web.http.DefaultCookieSerializer">

    </bean>-->


    <!--配置dao对象 批量扫描获取-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!--注入sqlsession-->
        <property name="sqlSessionFactoryBeanName" value="factoryBean"/>
        <!--指明要扫描的包-->
        <property name="basePackage" value="com.shop.mapper"/>

    </bean>

    <!--事务-->
    <!--配置事务管理器-->
    <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>

    <!--配置事务详情-->
    <tx:advice id="myAdvice" transaction-manager="txManager">
        <tx:attributes>
            <tx:method name="*" />
        </tx:attributes>
    </tx:advice>

    <!--aop-->
    <aop:config>
        <aop:advisor advice-ref="myAdvice" pointcut="execution(* com.shop.service.*.*(..) )"/>
    </aop:config>

</beans>

在附一下起动成功后的配置文件：

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xmlns:tx="http://www.springframework.org/schema/tx"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
                           http://www.springframework.org/schema/beans/spring-beans.xsd
                           http://www.springframework.org/schema/aop
                           http://www.springframework.org/schema/aop/spring-aop.xsd
                           http://www.springframework.org/schema/tx
                           http://www.springframework.org/schema/tx/spring-tx.xsd
                           http://www.springframework.org/schema/context
                           http://www.springframework.org/schema/context/spring-context.xsd">


    <!--注解开发，扫描要产生对象的包-->
    <context:component-scan base-package="com.shop"/>

    <!--加载连接池属性文件-->
    <context:property-placeholder location="classpath:db.properties"/>

    <context:property-placeholder
            location="classpath:redis.properties" file-encoding="UTF-8"
            ignore-unresolvable="true" ignore-resource-not-found="true" order="2"
            system-properties-mode="NEVER" />
    <!--配置c3p0连接池-->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${db.driver}"/>
        <property name="jdbcUrl" value="${db.url}"/>
        <property name="user" value="${db.username}"/>
        <property name="password" value="${db.password}"/>
        <property name="maxPoolSize" value="${c3p0.maxPoolSize}"/>
        <property name="minPoolSize" value="${c3p0.minPoolSize}"/>
        <property name="autoCommitOnClose" value="${c3p0.autoCommitOnClose}"/>
        <property name="checkoutTimeout" value="${c3p0.checkoutTimeout}"/>
        <property name="acquireRetryAttempts" value="${c3p0.acquireRetryAttempts}"/>
    </bean>

    <!--配置sqlSessionFacyory 产生sqlSesson对象-->
    <bean id="factoryBean" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <property name="typeAliasesPackage" value="com.shop.pojo"/>
        <!--扫描sql配置文件，mapper需要的xml文件-->
        <property name="mapperLocations" value="classpath:mapper/*.xml"/>
        <property name="configLocation" value="classpath:sqlMapConfig.xml"/>
    </bean>

    <bean id="keySerializer"
          class="org.springframework.data.redis.serializer.StringRedisSerializer"/>
    <bean id="valueSerializer"
          class="org.springframework.data.redis.serializer.GenericJackson2JsonRedisSerializer"/>
    <bean id="jedisPoolConfig" class="redis.clients.jedis.JedisPoolConfig">
        <property name="maxTotal" value="200"/>
        <property name="maxIdle" value="50"/>
        <property name="minIdle" value="8"/>
        <property name="maxWaitMillis" value="5000"/>
        <property name="numTestsPerEvictionRun" value="10"/>
        <property name="testOnBorrow" value="true"/>
        <property name="testOnReturn" value="true"/>
        <property name="testWhileIdle" value="true"/>
        <property name="timeBetweenEvictionRunsMillis" value="30000"/>
        <property name="minEvictableIdleTimeMillis" value="60000"/>
    </bean>
    <bean id="jedisConnectionFactory"
          class="org.springframework.data.redis.connection.jedis.JedisConnectionFactory">
        <property name="poolConfig" ref="jedisPoolConfig"/>
        <property name="hostName" value="localhost" />
        <property name="port" value="6379"/>
        <property name="password" value=""/>
        <property name="database" value="11"/>
        <property name="timeout" value="1800"/>
        <property name="usePool" value="true"/>
    </bean>
    <!-- redis template definition -->
    <bean id="redisTemplate" class="org.springframework.data.redis.core.StringRedisTemplate">
        <property name="connectionFactory" ref="jedisConnectionFactory"/>
        <property name="keySerializer" ref="keySerializer"/>
        <property name="valueSerializer" ref="valueSerializer"/>
        <property name="hashKeySerializer" ref="keySerializer"/>
        <property name="hashValueSerializer" ref="valueSerializer"/>
        <property name="enableTransactionSupport" value="false"/>
    </bean>
    <bean id="redisTemplateTransactional" class="org.springframework.data.redis.core.StringRedisTemplate">
        <property name="connectionFactory" ref="jedisConnectionFactory"/>
        <property name="keySerializer" ref="keySerializer"/>
        <property name="valueSerializer" ref="valueSerializer"/>
        <property name="hashKeySerializer" ref="keySerializer"/>
        <property name="hashValueSerializer" ref="valueSerializer"/>
        <property name="enableTransactionSupport" value="true"/>
    </bean>

    <!--配置dao对象 批量扫描获取-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!--注入sqlsession-->
        <property name="sqlSessionFactoryBeanName" value="factoryBean"/>
        <!--指明要扫描的包-->
        <property name="basePackage" value="com.shop.mapper"/>

    </bean>

    <!--事务-->
    <!--配置事务管理器-->
    <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource"/>
    </bean>
    <!--配置事务详情-->
    <tx:advice id="myAdvice" transaction-manager="txManager">
        <tx:attributes>
            <tx:method name="*"/>
        </tx:attributes>
    </tx:advice>

    <!--aop-->
    <aop:config>
        <aop:advisor advice-ref="myAdvice" pointcut="execution(* com.shop.service.*.*(..))"/>
    </aop:config>
</beans>

只不过是上面多了个没用的redis的约束，没关系的，测试了不是它的问题。自己也是一头雾水，为什么突然不好使了，问题为什么出现在spring配置文件中，然后这个配置文件我也没查出来哪的问题。重写一遍就好了，希望有懂得大神可以分享下经验。

有和我遇见同样问题得可以试试删掉spring，重新写一遍。