java.lang.IllegalStateException：无法创建子事件循环

Question

我只是使用Elasticsearch 5.0.0 Java API来搜索索引，然后搜索结果就出来了。但最终问题也会发生。

Exception in thread "main" java.lang.IllegalStateException: failed to create a child event loop 
    at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:88) 
    at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:58) 
    at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:47) 
    at io.netty.channel.MultithreadEventLoopGroup.<init>(MultithreadEventLoopGroup.java:58) 
    at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:77) 
    at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:72) 
    at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:59) 
    at org.elasticsearch.transport.netty4.Netty4Transport.createBootstrap(Netty4Transport.java:200) 
    at org.elasticsearch.transport.netty4.Netty4Transport.doStart(Netty4Transport.java:171) 
    at org.elasticsearch.common.component.AbstractLifecycleComponent.start(AbstractLifecycleComponent.java:68) 
    at org.elasticsearch.transport.TransportService.doStart(TransportService.java:182) 
    at org.elasticsearch.common.component.AbstractLifecycleComponent.start(AbstractLifecycleComponent.java:68) 
    at org.elasticsearch.client.transport.TransportClient.buildTemplate(TransportClient.java:169) 
    at org.elasticsearch.client.transport.TransportClient.<init>(TransportClient.java:228) 
    at org.elasticsearch.transport.client.PreBuiltTransportClient.<init>(PreBuiltTransportClient.java:69) 
    at org.elasticsearch.transport.client.PreBuiltTransportClient.<init>(PreBuiltTransportClient.java:65) 
    at util.ESUtil.getTransportClient(ESUtil.java:27) 
    at core.KKId2KKGeo.convertKKId2KKGeo(KKId2KKGeo.java:57) 
    at core.KKId2KKGeo.main(KKId2KKGeo.java:83) 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    at java.lang.reflect.Method.invoke(Method.java:498) 
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:144) 
Caused by: io.netty.channel.ChannelException: failed to open a new selector 
    at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:157) 
    at io.netty.channel.nio.NioEventLoop.<init>(NioEventLoop.java:148) 
    at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:126) 
    at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:36) 
    at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:84) 
... 23 more 
Caused by: java.io.IOException: Unable to establish loopback connection 
    at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:94) 
    at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:61) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at sun.nio.ch.PipeImpl.<init>(PipeImpl.java:171) 
    at sun.nio.ch.SelectorProviderImpl.openPipe(SelectorProviderImpl.java:50) 
    at java.nio.channels.Pipe.open(Pipe.java:155) 
    at sun.nio.ch.WindowsSelectorImpl.<init>(WindowsSelectorImpl.java:127) 
    at sun.nio.ch.WindowsSelectorProvider.openSelector(WindowsSelectorProvider.java:44) 
    at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:155) 
... 27 more 
Caused by: java.net.SocketException: No buffer space available (maximum connections reached?): connect 
    at sun.nio.ch.Net.connect0(Native Method) 
    at sun.nio.ch.Net.connect(Net.java:454) 
    at sun.nio.ch.Net.connect(Net.java:446) 
    at sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:648) 
    at java.nio.channels.SocketChannel.open(SocketChannel.java:189) 
    at sun.nio.ch.PipeImpl$Initializer$LoopbackConnector.run(PipeImpl.java:127) 
    at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:76) 
... 35 more 

这一些代码，我写的，通过ES 5.0.0的Java API搜索某些内容：

TransportClient client = new PreBuiltTransportClient(Settings.EMPTY) 
       .addTransportAddress(new  InetSocketTransportAddress(InetAddress.getByName("localhost"), 9300)); 
QueryBuilder qb = QueryBuilders.queryStringQuery(d_kkid); 
       SearchResponse searchResponse = client.prepareSearch("kkinfo_index") 
        .setScroll(new TimeValue(60000)) 
        .setQuery(qb) 
        .setSize(10).execute().actionGet(); 

Answer 1

我已经解决了我的问题，它是由我所编码不reasonale造成的。我的错误代码如下：

for(Object object : object_list){ 
    client = getTransportClient(); 
    //do ES search... 
} 

的reasonale代码是这样的：

client = getTransportClient(); 
for(Object object : object_list){ 
    // do ES search... 
}