引起：java.net.ConnectException：连接被拒绝：没有更多信息：localhost/127.0.0.1:9300

Question

I am developing a project from the link http://www.mkyong.com/spring-boot/spring-boot-spring-data-elasticsearch-example/ without any custom change yet.

My concerns is how we can run this project ? Do I need to install anything ?

org.elasticsearch.transport.ConnectTransportException: [][127.0.0.1:9300] connect_timeout[30s]
    at org.elasticsearch.transport.netty.NettyTransport.connectToChannelsLight(NettyTransport.java:967) ~[elasticsearch-2.4.4.jar:2.4.4]
    at org.elasticsearch.transport.netty.NettyTransport.connectToNode(NettyTransport.java:933) ~[elasticsearch-2.4.4.jar:2.4.4]
    at org.elasticsearch.transport.netty.NettyTransport.connectToNodeLight(NettyTransport.java:906) ~[elasticsearch-2.4.4.jar:2.4.4]
    at org.elasticsearch.transport.TransportService.connectToNodeLight(TransportService.java:267) ~[elasticsearch-2.4.4.jar:2.4.4]
    at org.elasticsearch.client.transport.TransportClientNodesService$SimpleNodeSampler.doSample(TransportClientNodesService.java:390) ~[elasticsearch-2.4.4.jar:2.4.4]
    at org.elasticsearch.client.transport.TransportClientNodesService$NodeSampler.sample(TransportClientNodesService.java:336) [elasticsearch-2.4.4.jar:2.4.4]
    at org.elasticsearch.client.transport.TransportClientNodesService.addTransportAddresses(TransportClientNodesService.java:187) [elasticsearch-2.4.4.jar:2.4.4]
    at org.elasticsearch.client.transport.TransportClient.addTransportAddress(TransportClient.java:243) [elasticsearch-2.4.4.jar:2.4.4]
    at com.mkyong.EsConfig.client(EsConfig.java:45) [classes/:na]
    at com.mkyong.EsConfig$$EnhancerBySpringCGLIB$$776c01dd.CGLIB$client$0(<generated>) [classes/:na]
    at com.mkyong.EsConfig$$EnhancerBySpringCGLIB$$776c01dd$$FastClassBySpringCGLIB$$c693023.invoke(<generated>) [classes/:na]
    at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228) [spring-core-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:356) [spring-context-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at com.mkyong.EsConfig$$EnhancerBySpringCGLIB$$776c01dd.client(<generated>) [classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_131]
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_131]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:1.8.0_131]
    at java.lang.reflect.Method.invoke(Unknown Source) ~[na:1.8.0_131]
    at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:162) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:588) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1173) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1067) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:208) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1138) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:835) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:741) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:467) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1173) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1067) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:513) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:208) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1138) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:585) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:366) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1264) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:761) [spring-beans-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:866) [spring-context-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:542) [spring-context-4.3.6.RELEASE.jar:4.3.6.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:737) [spring-boot-1.5.1.RELEASE.jar:1.5.1.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:370) [spring-boot-1.5.1.RELEASE.jar:1.5.1.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:314) [spring-boot-1.5.1.RELEASE.jar:1.5.1.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1162) [spring-boot-1.5.1.RELEASE.jar:1.5.1.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1151) [spring-boot-1.5.1.RELEASE.jar:1.5.1.RELEASE]
    at com.mkyong.Application.main(Application.java:26) [classes/:na]
Caused by: java.net.ConnectException: Connection refused: no further information: localhost/127.0.0.1:9300

pom.xml

<?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>

    <artifactId>springboot-springdata-elasticsearch-example</artifactId>
    <packaging>jar</packaging>
    <url>https://www.mkyong.com</url>
    <version>1.0</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>1.5.1.RELEASE</version>
    </parent>

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

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

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

        <!-- Runtime, for Embedded Elasticsearch,
            comment this if connect to external elastic search server-->
        <dependency>
            <groupId>net.java.dev.jna</groupId>
            <artifactId>jna</artifactId>
            <scope>runtime</scope>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <!-- Package as an executable jar/war -->
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

Answer 1

It is pretty clear that you have missed some or all of the steps in section 5.1 of the example that you are following. The last of them says that you must start the ElasticSearch instance. The evidence is that you haven't done this (successfully). The instance would be listing for connections on port 9300, It isn't, and that causes the OS to "refuse" the connection attempt by your client.

Prerequisite means that you must do them first.

Solution: follow the instructions.

Answer 2

Your code is expecting a server to be listening on port 9300 on localhost (probably an Elasticsearch server).

That server, however, is not running (connection refused). Refer to the documentation of your project. It probably requires/expects you to install and start a server before running your code.

If you need to do so, ES can be downloaded from here

Answer 3

there is a service called MySQL80 that should be running to connect to the database

for windows you can access it by searching for services than look for MySQL80 service and make sure it is running

I personally solved it by doing so