SpringBoot——报错总结

前言

记录SpringBoot的相关报错信息

错误

无法引入@ResponseBody和@RequestMapping("/")

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>

Failed to configure a DataSource: 'url'

Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.
source : https://www.cnblogs.com/javawxid/p/10949511.html

原因

1. DataSourceAutoConfiguration会自动加载.

2. 没有配置spring - datasource - url 属性.

3. spring - datasource - url 配置的地址格式有问题.

4. 配置 spring - datasource - url的文件没有加载.

解决

方案一 (解决原因1)[本人就是这种情况]
排除此类的autoconfig。启动以后就可以正常运行。

@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})
方案二 (解决原因2)
在application.properties/或者application.yml文件中没有添加数据库配置信息.

spring:
  datasource:
    url: jdbc:mysql://localhost:3306/read_data?useUnicode=true&characterEncoding=UTF-8&useSSL=false
    username: root
    password: 123456
    driver-class-name: com.mysql.jdbc.Driver
方案三 (解决原因3)
在spring xml配置文件中引用了数据库地址 所以需要对:等进行转义处理.但是在application.properties/或者application.yml文件并不需要转义,错误和正确方法写在下面了.

//错误示例
spring.datasource.url = jdbc:mysql://192.168.0.20:1504/f_me?setUnicode=true&characterEncoding=utf8
//正确示例
spring.datasource.url = jdbc:mysql://192.168.0.20:1504/f_me?setUnicode=true&characterEncoding=utf8
方案四 (解决原因4)
yml或者properties文件没有被扫描到,需要在pom文件中<build></build>添加如下.来保证文件都能正常被扫描到并且加载成功.

<!-- 如果不添加此节点mybatis的mapper.xml文件都会被漏掉。 -->
<resources>
    <resource>
        <directory>src/main/java</directory>
        <includes>
            <include>**/*.yml</include>
            <include>**/*.properties</include>
            <include>**/*.xml</include>
        </includes>
        <filtering>false</filtering>
    </resource>
    <resource>
        <directory>src/main/resources</directory>
        <includes>
            <include>**/*.yml</include>
            <include>**/*.properties</include>
            <include>**/*.xml</include>
        </includes>
        <filtering>false</filtering>
    </resource>
</resources>