在Spring Cloud中使用@RefreshScope重新加载Spring属性时出错

Question

我正在使用@RefreshScope注释测试spring-cloud的一个原型。 我为此使用了一个外部属性文件。 我已经在运行时参数中提供并配置了它。

pom.xml依赖项

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"   xsi:schemaLocation="http://maven.apache.org/POM/4.0.0      http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.1.1.RELEASE</version>
    <relativePath /> <!-- lookup parent from repository -->
</parent>
<groupId>com.proto.reload</groupId>
<artifactId>CachingService</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>CachingService</name>
<description>Demo project for cache</description>

<properties>
    <java.version>1.8</java.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-context</artifactId>
        <version>1.1.8.RELEASE</version>
    </dependency>

    <!-- <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-config-client</artifactId> 
        <version>1.1.3.RELEASE</version> </dependency> -->
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

这是主班

package com.proto.reload;

import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.builder.SpringApplicationBuilder;
import org.springframework.boot.context.ApplicationPidFileWriter;

@SpringBootApplication
public class CachingServiceApplication {

public static void main(String[] args) {
    if (args.length == 0) {
        System.out.println("Invalid Commandline argument. Please provide Consumer Properties file.");
        System.exit(0);
    }
    new SpringApplicationBuilder(CachingServiceApplication.class)
            .listeners(new ApplicationPidFileWriter())
            .properties("spring.config.name:" + args[0].replaceAll(".properties", ""))
            .build()
            .run(args);

    while (true) {
        try {
            Thread.sleep(2000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println(ConfigClass.getName());
    }
}

}

具有@RefreshScope批注的配置类

package com.proto.reload;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.cloud.context.config.annotation.RefreshScope;
import org.springframework.context.annotation.Configuration;

@Configuration
@RefreshScope
public class ConfigClass {

    private static String name;

    public static String getName() {
        return name;
    }

    @Value("${app.prop.name}")
    public void setName(String name) {
        this.name = name;
    }

}

这是我要传递参数的属性文件

app.prop.name=FirstOldValue

spring.pid.file=TestOne.pid

运行此代码时，出现以下错误。

   12:38:41.051 [main] DEBUG org.springframework.boot.context.logging.ClasspathLoggingApplicationListener - Application failed to start with classpath: [file:/C:/Program%20Files/Java/jre1.8.0_191/lib/resources.jar, file:/C:/Program%20Files/Java/jre1.8.0_191/lib/rt.jar, file:/C:/Program%20Files/Java/jre1.8.0_191/lib/jsse.jar, file:/C:/Program%20Files/Java/jre1.8.0_191/lib/jce.jar, file:/C:/Program%20Files/Java/jre1.8.0_191/lib/charsets.jar, file:/C:/Program%20Files/Java/jre1.8.0_191/lib/jfr.jar, file:/C:/Program%20Files/Java/jre1.8.0_191/lib/ext/access-bridge-64.jar, file:/C:/Program%20Files/Java/jre1.8.0_191/lib/ext/cldrdata.jar, ...]
12:38:41.105 [main] ERROR org.springframework.boot.SpringApplication - Application run failed
java.lang.NoSuchMethodError: org.springframework.boot.builder.SpringApplicationBuilder.<init>([Ljava/lang/Object;)V
    at org.springframework.cloud.bootstrap.BootstrapApplicationListener.bootstrapServiceContext(BootstrapApplicationListener.java:120)
    at org.springframework.cloud.bootstrap.BootstrapApplicationListener.onApplicationEvent(BootstrapApplicationListener.java:84)
    at org.springframework.cloud.bootstrap.BootstrapApplicationListener.onApplicationEvent(BootstrapApplicationListener.java:62)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139)
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:127)
    at org.springframework.boot.context.event.EventPublishingRunListener.environmentPrepared(EventPublishingRunListener.java:75)
    at org.springframework.boot.SpringApplicationRunListeners.environmentPrepared(SpringApplicationRunListeners.java:54)
    at org.springframework.boot.SpringApplication.prepareEnvironment(SpringApplication.java:347)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:306)
    at com.proto.reload.CachingServiceApplication.main(CachingServiceApplication.java:19)

我以错误的方式使用@RefreshScope吗？ 当我删除依赖项和@RefreshScope时，此代码可以正常工作，但在运行时不会更新属性值。 我的目标是在运行时加载修改后的属性值。

Answer 1

1.1.8.RELEASE Cloud的发布是Camden Release系列的一部分，该系列适用于Spring Boot 1.4.x版本。

请参阅“ Release Trains部分，了解用于您的Spring Boot版本的发行说明。

https://spring.io/projects/spring-cloud

目前他们是

发行火车启动版本

格林威治2.1.x

芬奇利2.0.x

Edgware 1.5.x

达斯顿1.5.x

当您使用Spring Boot 2.1.1时，您的依赖项管理应如下所示，请注意，因为Greenwich没有RELEASE但您需要添加里程碑存储库。

 <repositories>
    <repository>
        <id>spring-milestones</id>
        <name>Spring Milestones</name>
        <url>http://repo.spring.io/milestone</url>
        <snapshots>
            <enabled>false</enabled>
        </snapshots>
    </repository>
</repositories>

<dependencyManagement>
    <dependencies>
        <dependency>
            <groupId>org.springframework.cloud</groupId>
            <artifactId>spring-cloud-dependencies</artifactId>
            <version>Greenwich.RC2</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>
<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-context</artifactId>
    </dependency>

</dependencies>

Answer 2

添加云上下文权限，然后重试

<dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-context</artifactId>
        <version>1.1.8.RELEASE</version>
    </dependency>

更新：在同一元素上具有@Configuration和@RefreshScope只是一个无效的用例。 按照这个URL线程： https : //github.com/spring-cloud/spring-cloud-config/issues/43