java - 如何将一系列 application.properties 反序列化为 Java 中的 Map

Question

我有 Spring Boot 应用程序，application.properties 看起来像这样

com.mycompany.schedule.test=welcome
com.mycompany.schedule.test2=hi there

我希望将它们反序列化为Map

我尝试了以下方法和其他变体，但似乎不起作用

  private Map<String, String> schedules;

  @Value("${com.mycompany.schedule}")
  public void setSchedules(Map<String, String> values) {
    this.schedules = values;
  }

Answer 1

选项 1:

在您的配置类中，使用 @PropertySource 注释读取 application.properties 文件，如下所示。

MyAppConfiguration.java

import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.PropertySource;

@Configuration
@PropertySource(name = "customPropertySource", value = "classpath:application.properties")
public class MyAppConfiguration {

}

然后在您的POJO(或任何其他Spring组件)中，您可以通过Environment类来获取属性。

MyPojo.java

import java.util.Map;

import javax.annotation.PostConstruct;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.io.support.ResourcePropertySource;
import org.springframework.stereotype.Component;

@Component
public class MyPojo {

    @Autowired
    private ConfigurableEnvironment env;

    private Map<String, Object> schedules;

    @PostConstruct
    public void properties() {
        Object propSourceObj = env.getPropertySources().get("customPropertySource");
        if (propSourceObj instanceof ResourcePropertySource) {
            ResourcePropertySource propSource = (ResourcePropertySource) propSourceObj;
            setSchedules(propSource.getSource());
        }
        System.out.println("Schedules: " + getSchedules());

    }

    public Map<String, Object> getSchedules() {
        return schedules;
    }

    public void setSchedules(Map<String, Object> schedules) {
        this.schedules = schedules;
    }

}

请注意，使用此选项您将读取 application.properties 文件两次。如果您同意，您可以选择选项 1。否则，您可以选择选项 2。

选项 2:

MyAppConfiguration.java

import org.springframework.context.annotation.Configuration;

@Configuration
public class MyAppConfiguration {

}

MyPojo.java

import java.util.Map;

import javax.annotation.PostConstruct;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.env.OriginTrackedMapPropertySource;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.stereotype.Component;

@Component
public class MyPojo {

    @Autowired
    private ConfigurableEnvironment env;

    private Map<String, Object> schedules;

    @PostConstruct
    public void properties() {
        Object propSourceObj = env.getPropertySources().get("applicationConfig: [classpath:/application.properties]");
        if (propSourceObj instanceof OriginTrackedMapPropertySource) {
            OriginTrackedMapPropertySource propSource = (OriginTrackedMapPropertySource) propSourceObj;
            setSchedules(propSource.getSource());
        }
        System.out.println("Schedules: " + getSchedules());

    }

    public Map<String, Object> getSchedules() {
        return schedules;
    }

    public void setSchedules(Map<String, Object> schedules) {
        this.schedules = schedules;
    }

}

编辑:

抱歉，之前我误解了你的问题。如果您知道属性前缀，则可以使用 @ConfigurationProperties，如下所示。上面的选项是在不知道属性前缀的情况下读取所有属性。

MyAppConfiguration.java

import javax.annotation.PostConstruct;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Configuration;

@Configuration
public class MyAppConfiguration {

    @Autowired
    private MyCompanyConfigurationProperties myCompanyConfProps;

    @PostConstruct
    public void testProperteis() {
        System.out.println("My Properties: " + myCompanyConfProps.getSchedule());
    }

}

MyCompanyConfigurationProperties.java

import java.util.HashMap;
import java.util.Map;

import org.springframework.boot.context.properties.ConfigurationProperties;

@ConfigurationProperties(prefix = "com.mycompany")
public class MyCompanyConfigurationProperties {

    private Map<String, String> schedule = new HashMap<String, String>();

    public Map<String, String> getSchedule() {
        return schedule;
    }

    public void setSchedule(Map<String, String> schedule) {
        this.schedule = schedule;
    }

}