Когерентность: простой пользовательский адресProvider не работает

Question

Я пытался использовать address-provider для конфигурации well-known-addresses. Но это не работает.

Вот мой конфигурационный файл:

<?xml version='1.0'?> 

<coherence xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
      xmlns="http://xmlns.oracle.com/coherence/coherence-operational-config" 
      xsi:schemaLocation="http://xmlns.oracle.com/coherence/coherence-operational-config coherence-operational-config.xsd"> 
    <cluster-config> 
     <unicast-listener> 
      <well-known-addresses> 
       <address-provider> 
        <class-name>xilu.scratch.coherence.MyAddressProvider</class-name> 
       </address-provider> 
       <!-- 
       <socket-address id="1"> 
        <address>127.0.0.1</address> 
        <port>8888</port> 
       </socket-address> 
       --> 
      </well-known-addresses> 
      <address>127.0.0.1</address> 
      <port>8888</port> 
      <port-auto-adjust system-property="tangosol.coherence.localport.adjust"> 
       false 
      </port-auto-adjust> 
     </unicast-listener> 
    </cluster-config> 
</coherence> 

А вот мой адрес поставщика:

package xilu.scratch.coherence; 

import java.net.InetSocketAddress; 

/** 
* Created by xxilu on 5/18/16. 
*/ 
public class MyAddressProvider implements com.tangosol.net.AddressProvider { 

    private String[] addressList = { 
     "127.0.0.1", 
    }; 

    private int index = 0; 

    @Override 
    public InetSocketAddress getNextAddress() { 

    if(index >= 1) { 
     return null; 
    } 

    String addressText = addressList[index]; 

    index++; 

    InetSocketAddress addr = new InetSocketAddress(addressText, 8888); 

    return addr; 
    } 

    @Override 
    public void accept() { 
    } 

    @Override 
    public void reject(Throwable throwable) { 
    } 
} 

Это выглядит очень тривиально, но кластер не может быть сформирована. я войти, как это:

/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/bin/java -Dtangosol.coherence.log.level=9 -Djava.net.preferIPv4Stack=true -Didea.launcher.port=7537 "-Didea.launcher.bin.path=/Applications/IntelliJ IDEA 15.app/Contents/bin" -Dfile.encoding=UTF-8 -classpath "/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/charsets.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/deploy.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/ext/cldrdata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/ext/dnsns.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/ext/jaccess.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/ext/jfxrt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/ext/localedata.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/ext/nashorn.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/ext/sunec.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/ext/sunjce_provider.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/ext/sunpkcs11.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/ext/zipfs.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/javaws.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/jce.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/jfr.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/jfxswt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/jsse.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/management-agent.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/plugin.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/resources.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/jre/lib/rt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/lib/ant-javafx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/lib/dt.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/lib/javafx-mx.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/lib/jconsole.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/lib/packager.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/lib/sa-jdi.jar:/Library/Java/JavaVirtualMachines/jdk1.8.0_74.jdk/Contents/Home/lib/tools.jar:/Users/xxilu/Projects/scratch/Coherence1/out/production/Coherence1:/Users/xxilu/Oracle/Middleware/Oracle_Home/coherence/lib/coherence.jar:/Users/xxilu/Oracle/Middleware/Oracle_Home/oracle_common/modules/com.fasterxml.jackson.core.jackson-core.jar:/Users/xxilu/Oracle/Middleware/Oracle_Home/oracle_common/modules/com.fasterxml.jackson.jaxrs.jackson-jaxrs-json-provider.jar:/Users/xxilu/Oracle/Middleware/Oracle_Home/oracle_common/modules/com.fasterxml.jackson.core.jackson-databind.jar:/Users/xxilu/Oracle/Middleware/Oracle_Home/oracle_common/modules/com.fasterxml.jackson.core.jackson-annotations.jar:/Users/xxilu/Oracle/Middleware/Oracle_Home/oracle_common/modules/com.fasterxml.jackson.module.jackson-module-jaxb-annotations.jar:/Applications/IntelliJ IDEA 15.app/Contents/lib/idea_rt.jar" com.intellij.rt.execution.application.AppMain xilu.scratch.coherence.HelloWorld 
2016-05-19 00:19:42.117/1.064 Oracle Coherence 12.2.1.0.0 <Info> (thread=pool-1-thread-1, member=n/a): Loaded operational configuration from "jar:file:/Users/xxilu/Oracle/Middleware/Oracle_Home/coherence/lib/coherence.jar!/tangosol-coherence.xml" 
2016-05-19 00:19:42.198/1.136 Oracle Coherence 12.2.1.0.0 <Info> (thread=pool-1-thread-1, member=n/a): Loaded operational overrides from "jar:file:/Users/xxilu/Oracle/Middleware/Oracle_Home/coherence/lib/coherence.jar!/tangosol-coherence-override-dev.xml" 
2016-05-19 00:19:42.258/1.196 Oracle Coherence 12.2.1.0.0 <Info> (thread=pool-1-thread-1, member=n/a): Loaded operational overrides from "file:/Users/xxilu/Projects/scratch/Coherence1/out/production/Coherence1/tangosol-coherence-override.xml" 
2016-05-19 00:19:42.268/1.206 Oracle Coherence 12.2.1.0.0 <D5> (thread=pool-1-thread-1, member=n/a): Optional configuration override "cache-factory-config.xml" is not specified 
2016-05-19 00:19:42.269/1.207 Oracle Coherence 12.2.1.0.0 <D5> (thread=pool-1-thread-1, member=n/a): Optional configuration override "cache-factory-builder-config.xml" is not specified 
2016-05-19 00:19:42.269/1.208 Oracle Coherence 12.2.1.0.0 <D5> (thread=pool-1-thread-1, member=n/a): Optional configuration override "/custom-mbeans.xml" is not specified 
2016-05-19 00:19:42.270/1.208 Oracle Coherence 12.2.1.0.0 <D6> (thread=pool-1-thread-1, member=n/a): Loaded edition data from "jar:file:/Users/xxilu/Oracle/Middleware/Oracle_Home/coherence/lib/coherence.jar!/coherence-grid.xml" 

Oracle Coherence Version 12.2.1.0.0 Build 60603 
Grid Edition: Development mode 
Copyright (c) 2000, 2015, Oracle and/or its affiliates. All rights reserved. 

2016-05-19 00:19:42.798/1.736 Oracle Coherence GE 12.2.1.0.0 <Info> (thread=pool-1-thread-1, member=n/a): Loaded FMW commons version: 12.2.1-0-0-SNAPSHOT b60603 
2016-05-19 00:19:42.885/1.823 Oracle Coherence GE 12.2.1.0.0 <Info> (thread=pool-1-thread-1, member=n/a): Loaded cache configuration from "file:/Users/xxilu/Projects/scratch/Coherence1/out/production/Coherence1/coherence-cache-config.xml" 
2016-05-19 00:19:43.539/2.477 Oracle Coherence GE 12.2.1.0.0 <Info> (thread=pool-1-thread-1, member=n/a): The cluster name has not been configured, a value of "xxilu's cluster" has been automatically generated 
2016-05-19 00:19:43.567/2.506 Oracle Coherence GE 12.2.1.0.0 <Info> (thread=pool-1-thread-1, member=n/a): Created cache factory com.tangosol.net.ExtensibleConfigurableCacheFactory 
2016-05-19 00:19:44.020/2.958 Oracle Coherence GE 12.2.1.0.0 <Warning> (thread=pool-1-thread-1, member=n/a): Local address "127.0.0.1" is a loopback address; this cluster node will not connect to nodes located on different machines 
2016-05-19 00:19:44.069/3.008 Oracle Coherence GE 12.2.1.0.0 <D4> (thread=pool-1-thread-1, member=n/a): TCMP bound to /127.0.0.1:8888 using SystemDatagramSocketProvider 

И там останавливается.

Если я сменил поставщика адресов на стиль сокета-адреса (как указано в конфиге), все будет работать.

Answer 1

[Я отправил вопрос ранее для целей документации. Я потратил 10 часов на отладку этой проблемы, и я, наконец, нашел основную причину].

Проведя 10 часов, я нашел причину.

Существует одна очень тонкая деталь о реализации AddressProvider. В документе говорится, что getNextAddress должен вернуть null, чтобы указать, что все адреса исчерпаны. Но есть одна важная вещь, которую он не сказал: после возвращения null следующий вызов getNextAddress должен выглядеть как самый первый вызов этого объекта. Другим словом, если вы рассматриваете getNextAddress как итератор, итератору необходимо выполнить сброс после возврата завершающего null.

Так меняется MyAddressProvider от этого:

@Override 
public InetSocketAddress getNextAddress() { 
    if(index >= 1) { 
    return null; 
    } 
} 

Для этого:

@Override 
public InetSocketAddress getNextAddress() { 
    if(index >= 1) { 
    index = 0; 
    return null; 
    } 
} 

Все будет работать.

Надеюсь, это поможет людям, которые сталкиваются с подобной проблемой.