springboot项目启动报错Failed to configure a DataSource: 'url' attribute is not specified and no embedde

创建springboot项目后启动，报错为

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2019-09-26 09:54:41.640 ERROR 4392 --- [           main] o.s.b.d.LoggingFailureAnalysisReporter   : 

***************************
APPLICATION FAILED TO START
***************************

Description:

Failed to configure a DataSource: 'url' attribute is not specified and no embedded datasource could be configured.

Reason: Failed to determine a suitable driver class


Action:

Consider the following:
	If you want an embedded database (H2, HSQL or Derby), please put it on the classpath.
	If you have database settings to be loaded from a particular profile you may need to activate it (no profiles are currently active).

问题分析及解决方案

问题原因: Mybatis没有找到合适的加载类,其实是大部分spring - datasource - url没有加载成功,分析原因如下所示.

DataSourceAutoConfiguration会自动加载.
没有配置spring - datasource - url 属性.
spring - datasource - url 配置的地址格式有问题.
配置 spring - datasource - url的文件没有加载.

方案一 (解决原因1)

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)

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>

以上方法，任选其一就行