Java 如何使用 @Value Spring Annotation 注入 Map？

How to inject a Map using the @Value Spring Annotation?

提问by yathirigan

How can i inject values into a Map from the properties file using the @Value annotation in Spring ?

如何使用 Spring 中的 @Value 注释从属性文件中将值注入到 Map 中？

My Spring Java class is and i tried using the $ but, got the following error message

我的 Spring Java 类是，我尝试使用 $ 但是，收到以下错误消息

Could not autowire field: private java.util.Map Test.standard; nested exception is java.lang.IllegalArgumentException: Could not resolve placeholder 'com.test.standard' in string value "${com.test.standard}"

无法自动装配字段：private java.util.Map Test.standard; 嵌套异常是 java.lang.IllegalArgumentException：无法解析字符串值“${com.test.standard}”中的占位符“com.test.standard”

@ConfigurationProperty("com.hello.foo")
public class Test {

   @Value("${com.test.standard}")
   private Map<String,Pattern> standard = new LinkedHashMap<String,Pattern>

   private String enabled;

}

I have the following properties in a .properties file

我在 .properties 文件中有以下属性

com.test.standard.name1=Pattern1
com.test.standard.name2=Pattern2
com.test.standard.name3=Pattern3
com.hello.foo.enabled=true

采纳答案by luboskrnac

I believe Spring Boot supports loading properties maps out of the box with @ConfigurationPropertiesannotation.

我相信 Spring Boot 支持使用@ConfigurationProperties注释开箱即用地加载属性映射。

According that docs you can load properties:

根据该文档，您可以加载属性：

my.servers[0]=dev.bar.com
my.servers[1]=foo.bar.com

into bean like this:

像这样变成bean：

@ConfigurationProperties(prefix="my")
public class Config {

    private List<String> servers = new ArrayList<String>();

    public List<String> getServers() {
        return this.servers;
    }
}

I used @ConfigurationProperties feature before, but without loading into map. You need to use @EnableConfigurationProperties annotationto enable this feature.

我之前使用过 @ConfigurationProperties 功能，但没有加载到地图中。您需要使用@EnableConfigurationProperties 注解来启用此功能。

Cool stuff about this feature is that you can validate your properties.

这个功能很酷的一点是你可以验证你的属性。

回答by Arpit Aggarwal

You can inject .propertiesas a map in your class using @Resourceannotation.

您可以.properties使用@Resource注释在类中作为地图注入。

If you are working with XML based configuration,then add below bean in your spring configuration file:

如果您正在使用XML based configuration，则在您的 spring 配置文件中添加以下 bean：

 <bean id="myProperties" class="org.springframework.beans.factory.config.PropertiesFactoryBean">
      <property name="location" value="classpath:your.properties"/>
 </bean>

For, Annotation based:

对于，基于注解：

@Bean(name = "myProperties")
public static PropertiesFactoryBean mapper() {
        PropertiesFactoryBean bean = new PropertiesFactoryBean();
        bean.setLocation(new ClassPathResource(
                "your.properties"));
        return bean;
}

Then you can pick them up in your application as a Map:

然后您可以在您的应用程序中将它们作为 Map 提取：

@Resource(name = "myProperties")
private Map<String, String> myProperties;

回答by Michael Rahenkamp

You can inject values into a Map from the properties file using the @Valueannotation like this.

您可以使用这样的@Value注释从属性文件中将值注入到 Map 中。

The property in the properties file.

属性文件中的属性。

propertyname={key1:'value1',key2:'value2',....}

In your code.

在你的代码中。

@Value("#{${propertyname}}")  private Map<String,String> propertyname;

Note the hashtag as part of the annotation.

请注意将主题标签作为注释的一部分。

回答by Neil Han

Here is how we did it. Two sample classes as follow:

这是我们如何做到的。两个示例类如下：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.kafka.annotation.EnableKafka;
@EnableKafka
@Configuration
@EnableConfigurationProperties(KafkaConsumerProperties.class)
public class KafkaContainerConfig {

    @Autowired
    protected KafkaConsumerProperties kafkaConsumerProperties;

    @Bean
    public ConsumerFactory<String, String> consumerFactory() {
        return new DefaultKafkaConsumerFactory<>(kafkaConsumerProperties.getKafkaConsumerConfig());
    }
...

@Configuration
@ConfigurationProperties
public class KafkaConsumerProperties {
    protected Map<String, Object> kafkaConsumerConfig = new HashMap<>();

    @ConfigurationProperties("kafkaConsumerConfig")
    public Map<String, Object> getKafkaConsumerConfig() {
        return (kafkaConsumerConfig);
    }
...

To provide the kafkaConsumer config from a properties file, you can use: mapname[key]=value

要从属性文件提供 kafkaConsumer 配置，您可以使用：mapname[key]=value

//application.properties
kafkaConsumerConfig[bootstrap.servers]=localhost:9092, localhost:9093, localhost:9094
kafkaConsumerConfig[group.id]=test-consumer-group-local
kafkaConsumerConfig[value.deserializer]=org.apache.kafka.common.serialization.StringDeserializer
kafkaConsumerConfig[key.deserializer=org.apache.kafka.common.serialization.StringDeserializer

To provide the kafkaConsumer config from a yaml file, you can use "[key]": value In application.yml file:

要从 yaml 文件提供 kafkaConsumer 配置，您可以使用 "[key]": value 在 application.yml 文件中：

kafkaConsumerConfig:
  "[bootstrap.servers]": localhost:9092, localhost:9093, localhost:9094
  "[group.id]": test-consumer-group-local
  "[value.deserializer]": org.apache.kafka.common.serialization.StringDeserializer
  "[key.deserializer]": org.apache.kafka.common.serialization.StringDeserializer

回答by liuxun

I had a simple code for Spring Cloud Config

我有一个简单的 Spring Cloud Config 代码

like this:

像这样：

In application.properties

在 application.properties 中

spring.data.mongodb.db1=mongodb://[email protected]

spring.data.mongodb.db2=mongodb://[email protected]

spring.data.mongodb.db1=mongodb://[email protected]

spring.data.mongodb.db2=mongodb://[email protected]

read

读

@Bean(name = "mongoConfig")
@ConfigurationProperties(prefix = "spring.data.mongodb")
public Map<String, Map<String, String>> mongoConfig() {
    return new HashMap();
}

use

用

@Autowired
@Qualifier(value = "mongoConfig")
private Map<String, String> mongoConfig;

@Bean(name = "mongoTemplates")
public HashMap<String, MongoTemplate> mongoTemplateMap() throws UnknownHostException {
    HashMap<String, MongoTemplate> mongoTemplates = new HashMap<>();
    for (Map.Entry<String, String>> entry : mongoConfig.entrySet()) {
        String k = entry.getKey();
        String v = entry.getValue();
        MongoTemplate template = new MongoTemplate(new SimpleMongoDbFactory(new MongoClientURI(v)));
        mongoTemplates.put(k, template);
    }
    return mongoTemplates;
}

回答by wild_nothing

To get this working with YAML, do this:

要使其与 YAML 一起使用，请执行以下操作：

property-name: '{
  key1: "value1",
  key2: "value2"
}'

回答by ShareYourWisdom

Following worked for me:

以下为我工作：

SpingBoot 2.1.7.RELEASE

SpingBoot 2.1.7.RELEASE

YAML Property (Notice value sourrounded by single quotes)

YAML 属性（用单引号括起来的通知值）

property:
   name: '{"key1": false, "key2": false, "key3": true}'

In Java/Kotlin annotate field with (Notice use of #) (For java no need to escape '$' with '\')

在 Java/Kotlin 中使用 (Notice use of #) 注释字段（对于 Java 不需要用 '\' 转义 '$'）

@Value("#{${property.name}}")