背景
项目基于SpringBoot并且集成ElasticSearch，今天在编写测试类准备进行单元测试时，报了如下这个错误。
代码语言：javascript复制Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'client' defined in class path resource [com/lingyejun/project/ds/EsRepositoryConfig.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.elasticsearch.client.Client]: Factory method 'client' threw exception; nested exception is java.lang.IllegalStateException: availableProcessors is already set to [8], rejecting [8]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:590)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1256)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1105)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:543)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:503)
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:251)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1138)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1065)
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:818)
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:724)
... 94 more
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.elasticsearch.client.Client]: Factory method 'client' threw exception; nested exception is java.lang.IllegalStateException: availableProcessors is already set to [8], rejecting [8]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185)
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:582)
... 107 more
Caused by: java.lang.IllegalStateException: availableProcessors is already set to [8], rejecting [8]检查了原有代码是如下设置的
代码语言：javascript复制public static void main(String[] args) {
System.setProperty("es.set.netty.runtime.available.processors","false");
SpringApplication.run(TestApplication.class, args);
}解决
查阅资料后发现有两种解决方式
1. 将代码段：System.setProperty("es.set.netty.runtime.available.processors","false")；挪到静态代码块中。
如下：
代码语言：javascript复制static{
System.setProperty("es.set.netty.runtime.available.processors", "false");
}
public static void main(String[] args) {
SpringApplication.run(TestApplication.class, args);
}2.在jvm启动参数加上
代码语言：javascript复制-Des.set.netty.runtime.available.processors=false原因
此问题见：https://github.com/netty/netty/issues/6956
原因是程序的其余地方使用了Netty，如大部分项目也会同时使用Redis。这会影响在实例化传输客户端以前初始化处理器的数量。 因为在其余地方使用Netty，所以已经进行了初始化而且Netty会对此进行防范，所以首次实例化会因看到的非法状态异常而失败。
