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使用@Autowired Environment spring java Null指针异常读取属性文件

properties-file autowired maven spring java

hmahboob · 技术社区 · 7 年前

我正在尝试使用环境api注入属性文件。

代码:

@Component
@Configuration
@PropertySource("classpath:GeoFilter.properties")
public class CountryGeoFilter {

    @Autowired
    public Environment environment;

    @Bean
    public GeoFilterStore getCountryGeoFilter(String country) throws 
CountryNotFoundException, IOException {

    GeoFilterStore countryFilterStore = new GeoFilterStore();

    String value = environment.getProperty(country);
    if (value == null) {
        throw CountryNotFoundException.getBuilder(country).build();
    }
    String[] seperateValues = value.split(":");

    countryFilterStore.setGameStore(isTrueValue(seperateValues[0]));

    countryFilterStore.setVideoStore(isTrueValue(seperateValues[1]));
    return countryFilterStore;
    }

    private boolean isTrueValue(String possibleTrueValue) {
        return !possibleTrueValue.equals("No") && 
        !possibleTrueValue.equals("N/A");
    }
}

xml(src/main/resources)

<bean
    class="org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor" />

<bean
    class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
    <property name="location" value="classpath:GeoFilter.properties" />
</bean>

我还在web.xml中设置了contextparam

<context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:applicationContext.xml</param-value>
</context-param>

    CountryGeoFilter objGeo = new CountryGeoFilter();
    GeoFilterStore response = objGeo.getCountryGeoFilter(country);
    return response;

我对spring很陌生,不知道我会错在哪里。任何帮助都将不胜感激。

编辑:

我更新了启动代码以使用上下文

    ApplicationContext context = new 
    AnnotationConfigApplicationContext(CountryGeoFilter.class);
    CountryGeoFilter testGeoFilter = 
    context.getBean(CountryGeoFilter.class);
    testGeoFilter.getCountryGeoFilter(country);

现在我得到了以下异常

   Exception in thread "main" 
   org.springframework.beans.factory.UnsatisfiedDependencyException: 
   Error creating bean with name 'getCountryGeoFilter' defined in .. 
   Unsatisfied dependency expressed through method 
   'getCountryGeoFilter' parameter 
   0; nested exception is 
   org.springframework.beans.factory.NoSuchBeanDefinitionException: No 
   qualifying bean of type 'java.lang.String' available: expected at 
   least 1 bean which qualifies as autowire candidate. Dependency 
   annotations: {}

1 回复 | 直到 7 年前

Brian 7 年前

我在下面添加了一个基本的工作解决方案。从本质上讲,删除您的 getCountryGeoFilter()

此外,此配置没有使用任何XML配置。

TestClass.java

@Component
@Configuration
@PropertySource("classpath:test.properties")
public class TestClass {

    @Autowired
    Environment environment;

    public String test (String property) {

        final String value = environment.getProperty(property);

        System.out.println("========> Property: " + value);
        // TODO: Something with the prop val

        return value;

    }

}

prop1=prop_1_value
prop2=prop_2_value

TestController.java

@RestController
@RequestMapping("/test")
public class TestController {

    private TestClass testClass;

    TestController(TestClass testClass) {
        this.testClass = testClass;
    }

    @RequestMapping("/{propName}")
    public String test(@PathVariable String propName) {
        return testClass.test(propName);
    }

}