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以下记录本人在使用Spring Boot开发微服务的过程中遇到的一些问题：

Feign

当Spring Cloud版本为 Brixton.RELEASE ，会出现：

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Attribute 'value' in annotation [org.springframework.cloud.netflix.feign.FeignClient] must be declared as an @AliasFor [serviceId], not [name].

解决办法：
将Spring Cloud版本改为 Brixton.SR5 或 Camden.RELEASE ，即可解决此问题。

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目标：借助fastjson将json串解析成Java对象。json串及java对象结构如下：

json串

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{
    "positionData": {
        "deadReckoningPosition": {
            "lon": "111.91113900000000",
            "lat": "21.68800700000000"
        },
        "rawPosition": {
            "lon": "115.91113800000000",
            "lat": "28.68801700000000"
        },        
        "deltaPositionArray": [
            {
                "deltaTimeInSec": "0",
                "deltaLon": "0.00000000000000",
                "deltaLat": "0.00000000000000"
            },
            {
                "deltaTimeInSec": "1000",
                "deltaLon": "100.00000000000000",
                "deltaLat": "20.00000000000000"
            }
        ],
        "heading": "10",
        "visibleSatelliteNumber": "5",
        "altitude": "2",
        "rawPositionUncertaintyEstimate": "3"
    }
}

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最近在做微服务开发，项目中使用spring boot, eureka, feign, hystrix, swagger1等，结果在项目启动时，发现feignclient总是注入失败，抛出空指针异常：

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Caused by: java.lang.NullPointerException: null
    at com.mangofactory.swagger.models.property.field.FieldModelPropertyProvider.propertiesForSerialization(FieldModelPropertyProvider.java:54) ~[swagger-models-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.models.property.provider.DefaultModelPropertiesProvider.propertiesForSerialization(DefaultModelPropertiesProvider.java:34) ~[swagger-models-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.models.DefaultModelProvider.properties(DefaultModelProvider.java:104) ~[swagger-models-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.models.DefaultModelProvider.modelFor(DefaultModelProvider.java:54) ~[swagger-models-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.readers.ApiModelReader.execute(ApiModelReader.java:71) ~[swagger-springmvc-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.readers.ApiModelReader.execute(ApiModelReader.java:39) ~[swagger-springmvc-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.core.CommandExecutor.execute(CommandExecutor.java:13) ~[swagger-springmvc-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.scanners.ApiListingScanner.scan(ApiListingScanner.java:100) ~[swagger-springmvc-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.core.SwaggerApiResourceListing.initialize(SwaggerApiResourceListing.java:72) ~[swagger-springmvc-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.plugin.SwaggerSpringMvcPlugin.initialize(SwaggerSpringMvcPlugin.java:427) ~[swagger-springmvc-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.plugin.SwaggerPluginAdapter.onApplicationEvent(SwaggerPluginAdapter.java:51) ~[swagger-springmvc-1.0.2.jar:1.0.2]
    at com.mangofactory.swagger.plugin.SwaggerPluginAdapter.onApplicationEvent(SwaggerPluginAdapter.java:21) ~[swagger-springmvc-1.0.2.jar:1.0.2]
    at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:166) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:138) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:382) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:388) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:336) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:877) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544) ~[spring-context-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.cloud.context.named.NamedContextFactory.createContext(NamedContextFactory.java:110) ~[spring-cloud-context-1.1.1.RELEASE.jar:1.1.1.RELEASE]
    at org.springframework.cloud.context.named.NamedContextFactory.getContext(NamedContextFactory.java:79) ~[spring-cloud-context-1.1.1.RELEASE.jar:1.1.1.RELEASE]
    at org.springframework.cloud.context.named.NamedContextFactory.getInstance(NamedContextFactory.java:115) ~[spring-cloud-context-1.1.1.RELEASE.jar:1.1.1.RELEASE]
    at org.springframework.cloud.netflix.feign.FeignClientFactoryBean.getOptional(FeignClientFactoryBean.java:148) ~[spring-cloud-netflix-core-1.1.5.RELEASE.jar:1.1.5.RELEASE]
    at org.springframework.cloud.netflix.feign.FeignClientFactoryBean.feign(FeignClientFactoryBean.java:93) ~[spring-cloud-netflix-core-1.1.5.RELEASE.jar:1.1.5.RELEASE]
    at org.springframework.cloud.netflix.feign.FeignClientFactoryBean.getObject(FeignClientFactoryBean.java:166) ~[spring-cloud-netflix-core-1.1.5.RELEASE.jar:1.1.5.RELEASE]
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:168) ~[spring-beans-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    ... 47 common frames omitted
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GitHub提供了两种形式的”Fork me on Github”（左上角\右上角），具体样式详见GitHub Ribbons官网。

比如，在本博客中加入GitHub Ribbon，只需要拷贝以下代码到themes\{hexo-theme-next}\layout\_layout.swing的</body>标签之前。

1
<a href="https://github.com/you"><img style="position: absolute; top: 0; right: 0; border: 0;" src="https://camo.githubusercontent.com/365986a132ccd6a44c23a9169022c0b5c890c387/68747470733a2f2f73332e616d617a6f6e6177732e636f6d2f6769746875622f726962626f6e732f666f726b6d655f72696768745f7265645f6161303030302e706e67" alt="Fork me on GitHub" data-canonical-src="https://s3.amazonaws.com/github/ribbons/forkme_right_red_aa0000.png"></a>

拷贝时注意将https://github.com/you中的you改为本人的github名字。

最终效果可见博客首页右上角。
如果不是Hexo博客或非NexT主题样式，请自行查找更改相关主题文件。

Luoml's blog

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　　君子曰：学不可以已。
　　青，取之于蓝而青于蓝；冰，水为之而寒于水。木直中绳，輮^1以为轮，其曲中规。虽有槁暴^2，不复挺者，輮使之然也。故木受绳则直，金就砺则利，君子博学而日参省乎己，则知明而行无过矣。
　　故不登高山，不知天之高也；不临深溪，不知地之厚也；不闻先王之遗言，不知学问之大也。干、越、夷、貉之子，生而同声，长而异俗，教使之然也。诗曰：“嗟尔君子，无恒安息。靖共尔位，好是正直。神之听之，介尔景福。”神莫大于化道，福莫长于无祸。
　　吾尝终日而思矣，不如须臾之所学也；吾尝跂而望矣，不如登高之博见也。登高而招，臂非加长也，而见者远；顺风而呼，声非加疾也，而闻者彰。假舆马者，非利足也，而致千里；假舟楫者，非能水也，而绝江河。君子生非异也，善假于物也。

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Fork me on GitHub