Question

我有以下代码：

application.yml
security:
  section1:
    key1: "value1"
    key2: "value2"
  section2:
    key1: "value1"
    key2: "value2"

//Main class
@SpringBootApplication
public class DemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(DemoApplication.class, args);
    }

}

服务等级

@Service
public class DemoService {

    private Map<String,Section1Properties>projects=new HashMap<String,Section1Properties>();
    @Autowired
    public DemoService(SecurityProperties security) {
        this.projects=security.myConfig1();
        projects.get("section1").getKey1();
        projects.get("section1").getKey2();
    }

}

配置类

@Configuration
@EnableConfigurationProperties
@ConfigurationProperties(prefix = "security")
public class SecurityProperties implements Serializable{

    private static final long serialVersionUID = 1L;
    private String section1;
    private String section2;
    private Map<String,Section1Properties> sec1=new HashMap<String,Section1Properties>();
    private Map<String,Section2Properties> sec2=new HashMap<String,Section2Properties>();

    public Map<String,Section1Properties> myConfig1(){
        return sec1;
    }   
    public Map<String,Section2Properties> myConfig2(){
        return sec2;
    }
    public String getSection1() {
        return section1;
    }

    public void setSection1(String section1) {
        this.section1 = section1;
    }

    public String getSection2() {
        return section2;
    }

    public void setSection2(String section2) {
        this.section2 = section2;
    }

    public static class Section1Properties{
    private String key1;
     private String key2;
    public String getKey1() {
        return key1;
    }
    public void setKey1(String key1) {
        this.key1 = key1;
    }
    public String getKey2() {
        return key2;
    }
    public void setKey2(String key2) {
        this.key2 = key2;
    }
}

    public static class Section2Properties{
        private String key1;
         private String key2;
        public String getKey1() {
            return key1;
        }
        public void setKey1(String key1) {
            this.key1 = key1;
        }
        public String getKey2() {
            return key2;
        }
        public void setKey2(String key2) {
            this.key2 = key2;
        }
    }
}

运行此代码时，出现如下所示的错误。

org.springframework.beans.factory.BeanCreationException：创建文件[C：\ Users \ ABC \ eclipse-workspace \ demo \ target \ classes \ com \ demo \ DemoService.class]中定义的名称为'demoService'的bean时出错：通过构造函数实例化Bean失败；嵌套的异常是org.springframework.beans.BeanInstantiationException：无法实例化[com.demo.DemoService]：构造方法引发了异常；嵌套的异常是java.lang.NullPointerException 在org.springframework.beans.factory.support.ConstructorResolver.instantiate（ConstructorResolver.java:314）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor（ConstructorResolver.java:295）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor（AbstractAutowireCapableBeanFactory.java:1358）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance（AbstractAutowireCapableBeanFactory.java:1204）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean（AbstractAutowireCapableBeanFactory.java:557）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean（AbstractAutowireCapableBeanFactory.java:517）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.AbstractBeanFactory.lambda $ doGetBean $ 0（AbstractBeanFactory.java:323）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton（DefaultSingletonBeanRegistry.java:222）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean（AbstractBeanFactory.java:321）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.AbstractBeanFactory.getBean（AbstractBeanFactory.java:202）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons（DefaultListableBeanFactory.java:879）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization（AbstractApplicationContext.java:878）〜[spring-context-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.context.support.AbstractApplicationContext.refresh（AbstractApplicationContext.java:550）〜[spring-context-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh（ServletWebServerApplicationContext.java:141）〜[spring-boot-2.2.2.RELEASE.jar：2.2.2.RELEASE] 在org.springframework.boot.SpringApplication.refresh（SpringApplication.java:747）上[spring-boot-2.2.2.RELEASE.jar：2.2.2.RELEASE] 在org.springframework.boot.SpringApplication.refreshContext（SpringApplication.java:397）[spring-boot-2.2.2.RELEASE.jar：2.2.2.RELEASE] 在org.springframework.boot.SpringApplication.run（SpringApplication.java:315）[spring-boot-2.2.2.RELEASE.jar：2.2.2.RELEASE] 在org.springframework.boot.SpringApplication.run（SpringApplication.java:1226）上[spring-boot-2.2.2.RELEASE.jar：2.2.2.RELEASE] 在org.springframework.boot.SpringApplication.run（SpringApplication.java:1215）上[spring-boot-2.2.2.RELEASE.jar：2.2.2.RELEASE] 在com.demo.DemoApplication.main（DemoApplication.java:10）[classes /：na] 由以下原因导致：org.springframework.beans.BeanInstantiationException：无法实例化[com.demo.DemoService]：构造函数引发了异常；嵌套的异常是java.lang.NullPointerException 在org.springframework.beans.BeanUtils.instantiateClass（BeanUtils.java:213）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate（SimpleInstantiationStrategy.java:117）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] 在org.springframework.beans.factory.support.ConstructorResolver.instantiate（ConstructorResolver.java:310）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] ...省略了19个通用框架引起原因：java.lang.NullPointerException：null 在com.demo.DemoService。（DemoService.java:18）〜[classes /：na] 在sun.reflect.NativeConstructorAccessorImpl.newInstance0（本地方法）〜[na：1.8.0_231] 在sun.reflect.NativeConstructorAccessorImpl.newInstance（NativeConstructorAccessorImpl.java:62）〜[na：1.8.0_231] 在sun.reflect.DelegatingConstructorAccessorImpl.newInstance（DelegatingConstructorAccessorImpl.java:45）〜[na：1.8.0_231] 在java.lang.reflect.Constructor.newInstance（Constructor.java:423）〜[na：1.8.0_231] 在org.springframework.beans.BeanUtils.instantiateClass（BeanUtils.java:200）〜[spring-beans-5.2.2.RELEASE.jar：5.2.2.RELEASE] ...省略了21个常见框架

服务类，可从yml文件中读取数据

0 个答案: