java - Spring Boot - 从属性文件注入(inject)映射

Question

这个问题在这里已经有了答案:





How to fill HashMap from java property file with Spring @Value

(8 个回答)


1年前关闭。




属性文件如下所示:

url1=path_to_binary1
url2=path_to_binary2

根据 this我尝试了以下方法:

@Component
@EnableConfigurationProperties
public class ApplicationProperties {
    private Map<String, String> pathMapper;

    //get and set
}

在另一个组件中，我 Autowiring 了 ApplicationProperties:

@Autowired
private ApplicationProperties properties;         
      //inside some method:
      properties.getPathMapper().get(appName);

生产 NullPointerException .

如何纠正它？

更新

根据 user7757360 的建议，我有正确的建议:

@Component
@EnableConfigurationProperties
@ConfigurationProperties(prefix="app")
public class ApplicationProperties {

和属性文件:

app.url1=path_to_binary1
app.url2=path_to_binary2

还是不行

更新 2

@Component
@EnableConfigurationProperties
@ConfigurationProperties(prefix="app")
public class ApplicationProperties {
    private Map<String, String> app;

和里面 application.properties :

app.url1=path_to_binary1
app.url2=path_to_binary2

还是不行

Answer 1

如果您可以为属性文件提供更具体的示例，将会很有帮助。您应该在 url1 和 url2 中具有相同的前缀，然后您可以使用
@ConfigurationProperties(prefix="my")
如在

my.pathMapper.url1=path_to_binary1
my.pathMapper.url2=path_to_binary2


@Component
@EnableConfigurationProperties
@ConfigurationProperties(prefix="my")
public class ApplicationProperties {
    private Map<String, String> pathMapper;

    //get and set for pathMapper are important
}

更多信息请访问 https://docs.spring.io/spring-boot/docs/current/reference/html/boot-features-external-config.html#boot-features-external-config-loading-yaml