创建博客过程中遇到的问题

运行时出现找不到MappingJacksonHttpMessageConverter的情况

 

[org.springframework.web.context.ContextLoader]Context initialization failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter#0'
... ...
Caused by: org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [org.springframework.http.converter.json.MappingJacksonHttpMessageConverter] for bean with name 'org.springframework.http.converter.json.MappingJacksonHttpMessageConverter#2aa148c0'
... ...
Caused by: java.lang.ClassNotFoundException: org.springframework.http.converter.json.MappingJacksonHttpMessageConverter
... ...

 

原因是Spring 3.x 和4.X处理JSON的一个类不一样,而这个东西又配置在xml文件中,所以编译时又无法发现

spring3.x是org.springframework.http.converter.json.MappingJacksonHttpMessageConverter

spring4.x是org.springframework.http.converter.json.MappingJackson2HttpMessageConverter

1. 查找替换所有XML中名字

2. 同时加入最新的FastJackson依赖

<dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-core</artifactId>
                <version>2.8.5</version>
            </dependency>
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-databind</artifactId>
                <version>2.8.5</version>
            </dependency>
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-annotations</artifactId>
                <version>2.8.5</version>
            </dependency>

注意看这里:

Spring 3.x 升级到Spring 4.x 注意事项和步骤,错误解决方法

MySql 数据库更新为8.0及以上后,对应的应用程序数据库链接驱动包也要更新为8.0版本。否则会报驱动异常。
需要注意以下几点:
1.最新驱动包Maven下载配置如下:

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.11</version>
</dependency>

2.JDBC配置表更新如下:
以前的版本:

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://xxx.xx.xx.xxx:3306/db?characterEncoding=utf-8
jdbc.username=root
jdbc.password=admin

现在的版本:

jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://xxx.xx.xx.xxx:3306/db?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT%2B8 
jdbc.username=root
jdbc.password=admin

其中jdbc.driver=com.mysql.cj.jdbc.Driverjdbc.url=jdbc:mysql://xxx.xx.xx.xxx:3306/db?useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT%2B8中的useUnicode=true&characterEncoding=utf-8&useSSL=false&serverTimezone=GMT%2B8为新加入的东西。

 

posted @ 2019-11-14 23:31  doyi  阅读(232)  评论(0编辑  收藏  举报