Issue 1:
I have searched the issues of this repository and believe that this is not a duplicate.

I have checked the FAQ of this repository and believe that this is not a duplicate.

Environment

Dubbo version: 2.6.2

Operating System version: centos

Java version: 1.8.0_144

Step to reproduce this issue

ip获取工具错误导致 StackOverflowError

Expected Result

不报错

Actual Result

报错，不能启动

If there is an exception, please attach the exception trace:

187 "main" #1 prio=5 os_prio=0 tid=0x00007f817000b000 nid=0x48ce in Object.wait() [0x00007f817645b000]
188 java.lang.Thread.State: WAITING (on object monitor)
189 at java.lang.Object.wait(Native Method)
190 at java.lang.Object.wait(Object.java:502)
191 at java.net.InetAddress.checkLookupTable(InetAddress.java:1393)
192 - locked <0x00000005c07e62a8> (a java.util.HashMap)
193 at java.net.InetAddress.getAddressesFromNameService(InetAddress.java:1310)
194 at java.net.InetAddress.getLocalHost(InetAddress.java:1500)
195 - locked <0x00000005c07e6298> (a java.lang.Object)
196 at com.alibaba.dubbo.common.utils.NetUtils.getLocalAddress0(NetUtils.java:188)
197 at com.alibaba.dubbo.common.utils.NetUtils.getLocalAddress(NetUtils.java:180)
198 at com.alibaba.dubbo.common.utils.NetUtils.getLocalHost(NetUtils.java:146)
199 at com.alibaba.dubbo.common.logger.support.FailsafeLogger.appendContextMessage(FailsafeLogger.java:40)
200 at com.alibaba.dubbo.common.logger.support.FailsafeLogger.warn(FailsafeLogger.java:110)
201 at com.alibaba.dubbo.common.utils.NetUtils.getLocalAddress0(NetUtils.java:220)
202 at com.alibaba.dubbo.common.utils.NetUtils.getLocalAddress(NetUtils.java:180)
203 at com.alibaba.dubbo.common.utils.NetUtils.getLocalHost(NetUtils.java:146)
204 at com.alibaba.dubbo.common.logger.support.FailsafeLogger.appendContextMessage(FailsafeLogger.java:40)
205 at com.alibaba.dubbo.common.logger.support.FailsafeLogger.error(FailsafeLogger.java:134)
206 at com.alibaba.dubbo.common.utils.NetUtils.getLocalAddress0(NetUtils.java:222)
207 at com.alibaba.dubbo.common.utils.NetUtils.getLocalAddress(NetUtils.java:180)
208 at com.alibaba.dubbo.common.utils.NetUtils.getLocalHost(NetUtils.java:146)
209 at com.alibaba.dubbo.common.logger.support.FailsafeLogger.appendContextMessage(FailsafeLogger.java:40)
210 at com.alibaba.dubbo.common.logger.support.FailsafeLogger.warn(FailsafeLogger.java:110)
211 at com.alibaba.dubbo.common.utils.NetUtils.getLocalAddress0(NetUtils.java:220)
212 at com.alibaba.dubbo.common.utils.NetUtils.getLocalAddress(NetUtils.java:180)
213 at com.alibaba.dubbo.common.utils.NetUtils.getLocalHost(NetUtils.java:146)
214 at com.alibaba.dubbo.common.logger.support.FailsafeLogger.appendContextMessage(FailsafeLogger.java:40)
215 at com.alibaba.dubbo.common.logger.support.FailsafeLogger.error(FailsafeLogger.java:134)
216 at com.alibaba.dubbo.common.utils.NetUtils.getLocalAddress0(NetUtils.java:222)
217 at com.alibaba.dubbo.common.utils.NetUtils.getLocalAddress(NetUtils.java:180)
218 at com.alibaba.dubbo.common.utils.NetUtils.getLocalHost(NetUtils.java:146)
219 at com.alibaba.dubbo.common.logger.support.FailsafeLogger.appendContextMessage(FailsafeLogger.java:40)

Issue 2:
I have searched the issues of this repository and believe that this is not a duplicate.

I have checked the FAQ of this repository and believe that this is not a duplicate.

Environment

Dubbo version: 2.6.5

Operating System version: win10

Java version: 1.8

Steps to reproduce this issue

dubbo spi 扩展列表有 exception=com.alibaba.dubbo.rpc.filter.ExceptionFilter

我自己实现了一个 filter 扩展，名为 exception=xxxFilter

debug com.alibaba.dubbo.common.extension.ExtensionLoader#loadClass 将抛出 throw new IllegalStateException("Duplicate extension "......)

Expected Result

此异常被 exceptions 获取后，不抛出来，理论上不应该抛出来给用户吗，否则将被加载 jar 包的顺序影响，如果在 dubbo 生效之前加载，自己的 filter 就起作用，否则不起作用

Actual Result

捕获异常后没有任何提示信息