[Java知识库]问题Error querying database. Cause: java.lang.NullPointerException解决方法

Error querying database. Cause: java.lang.NullPointerException

遇到此类问题主要主要查看springBoot配置文件与实际配置jdbc类的是否配置成功
错误原因
注意我这配置的是Spring.datasource.xxx
配置文件 application.properties

spring.datasource.url=jdbc:mysql://localhost:3306/springboot
spring.datasource.username=root
spring.datasource.password=123456
spring.datasource.driver-class-name=com.mysql.jdbc.Driver

logging.level.cpm.lmy = debug

spring.datasource.hikari.idle-timeout=60000
spring.datasource.hikari.minimum-idle=10
spring.datasource.hikari.maximum-pool-size=30

server.port=8086
mybatis.type-aliases-package=cpm.lmy.pojo
mybatis.mapper-locations=classpath*:mappers/*.xml

jdbc类注意我配置的是配置文件前缀是jdbc

import org.springframework.boot.context.properties.ConfigurationProperties;
***********************
//错误在这不应该是jdbc而是配置文件中spring.datasource
***********************
@ConfigurationProperties(prefix = "jdbc")


public class JdbcProperties {
    private String url;
    private String driverClassName;
    private String username;
    private String password;

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public String getDriverClassName() {
        return driverClassName;
    }

    public void setDriverClassName(String driverClassName) {
        this.driverClassName = driverClassName;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public String getPassword() {
        return password;
    }

    public void setPassword(String password) {
        this.password = password;
    }
}

jdbc类注意我配置的是配置文件前缀是jdbc
但是配置文件 application.properties 中配置的是 注意我这配置的是Spring.datasource.xxx导致无法读取无法生成对象导致Error querying database. Cause: java.lang.NullPointerException,改为一致就可以解决Bug
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