Unable to import Maven project into IntelliJ IDEA2017

在win7下用IntelliJ IDEA2017创建了一个maven project， 却一直提示“Unable to import Maven project”的错误。从IDEA的Help>Show log里发现如下信息。

2017-09-19 16:57:17,318 [  78794]   WARN - ution.rmi.RemoteProcessSupport - The cook failed to start due to java.net.ConnectException: Connection refused: connect 
2017-09-19 16:57:19,428 [  80904]   WARN -      #org.jetbrains.idea.maven - Cannot reconnect. 
java.lang.RuntimeException: Cannot reconnect.
	at org.jetbrains.idea.maven.server.RemoteObjectWrapper.perform(RemoteObjectWrapper.java:111)
	at org.jetbrains.idea.maven.server.MavenIndexerWrapper.createIndex(MavenIndexerWrapper.java:61)
	at org.jetbrains.idea.maven.indices.MavenIndex.createContext(MavenIndex.java:362)
	at org.jetbrains.idea.maven.indices.MavenIndex.access$600(MavenIndex.java:48)
	at org.jetbrains.idea.maven.indices.MavenIndex$IndexData.<init>(MavenIndex.java:665)
	at org.jetbrains.idea.maven.indices.MavenIndex.doOpen(MavenIndex.java:206)
	at org.jetbrains.idea.maven.indices.MavenIndex.open(MavenIndex.java:172)
	at org.jetbrains.idea.maven.indices.MavenIndex.<init>(MavenIndex.java:102)
	at org.jetbrains.idea.maven.indices.MavenIndices.add(MavenIndices.java:92)
	at org.jetbrains.idea.maven.indices.MavenIndicesManager.ensureIndicesExist(MavenIndicesManager.java:174)
	at org.jetbrains.idea.maven.indices.MavenProjectIndicesManager$3.run(MavenProjectIndicesManager.java:117)
	at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:337)
	at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:327)
	at com.intellij.util.ui.update.MergingUpdateQueue.lambda$flush$1(MergingUpdateQueue.java:277)
	at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:291)
	at com.intellij.util.ui.update.MergingUpdateQueue.run(MergingUpdateQueue.java:246)
	at com.intellij.util.concurrency.QueueProcessor.runSafely(QueueProcessor.java:246)
	at com.intellij.util.Alarm$Request.runSafely(Alarm.java:417)
	at com.intellij.util.Alarm$Request.access$700(Alarm.java:344)
	at com.intellij.util.Alarm$Request$1.run(Alarm.java:384)
	at com.intellij.util.Alarm$Request.run(Alarm.java:395)
	at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at com.intellij.util.concurrency.SchedulingWrapper$MyScheduledFutureTask.run(SchedulingWrapper.java:237)
	at com.intellij.util.concurrency.BoundedTaskExecutor$2.run(BoundedTaskExecutor.java:212)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
	at java.lang.Thread.run(Thread.java:745)
Caused by: java.rmi.RemoteException: Cannot start maven service; nested exception is: 
	java.rmi.ConnectException: Connection refused to host: localhost; nested exception is: 
	java.net.ConnectException: Connection refused: connect
	at org.jetbrains.idea.maven.server.MavenServerManager.create(MavenServerManager.java:175)
	at org.jetbrains.idea.maven.server.MavenServerManager.create(MavenServerManager.java:80)
	at org.jetbrains.idea.maven.server.RemoteObjectWrapper.getOrCreateWrappee(RemoteObjectWrapper.java:41)
	at org.jetbrains.idea.maven.server.MavenServerManager$4.create(MavenServerManager.java:522)
	at org.jetbrains.idea.maven.server.MavenServerManager$4.create(MavenServerManager.java:518)
	at org.jetbrains.idea.maven.server.RemoteObjectWrapper.getOrCreateWrappee(RemoteObjectWrapper.java:41)
	at org.jetbrains.idea.maven.server.MavenIndexerWrapper.getRemoteId(MavenIndexerWrapper.java:169)
	at org.jetbrains.idea.maven.server.MavenIndexerWrapper.access$100(MavenIndexerWrapper.java:37)
	at org.jetbrains.idea.maven.server.MavenIndexerWrapper$1.execute(MavenIndexerWrapper.java:64)
	at org.jetbrains.idea.maven.server.RemoteObjectWrapper.perform(RemoteObjectWrapper.java:105)
	... 27 more
Caused by: java.rmi.ConnectException: Connection refused to host: localhost; nested exception is: 
	java.net.ConnectException: Connection refused: connect
	at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:619)
	at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:216)
	at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:202)
	at sun.rmi.server.UnicastRef.newCall(UnicastRef.java:342)
	at sun.rmi.registry.RegistryImpl_Stub.lookup(Unknown Source)
	at com.intellij.execution.rmi.RemoteProcessSupport.b(RemoteProcessSupport.java:257)
	at com.intellij.execution.rmi.RemoteUtil.executeWithClassLoader(RemoteUtil.java:232)
	at com.intellij.execution.rmi.RemoteProcessSupport.a(RemoteProcessSupport.java:255)
	at com.intellij.execution.rmi.RemoteProcessSupport.acquire(RemoteProcessSupport.java:161)
	at org.jetbrains.idea.maven.server.MavenServerManager.create(MavenServerManager.java:172)
	... 36 more
Caused by: java.net.ConnectException: Connection refused: connect
	at java.net.TwoStacksPlainSocketImpl.socketConnect(Native Method)
	at java.net.AbstractPlainSocketImpl.doConnect(AbstractPlainSocketImpl.java:350)
	at java.net.AbstractPlainSocketImpl.connectToAddress(AbstractPlainSocketImpl.java:206)
	at java.net.AbstractPlainSocketImpl.connect(AbstractPlainSocketImpl.java:188)
	at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
	at java.net.SocksSocketImpl.connect(SocksSocketImpl.java:392)
	at java.net.Socket.connect(Socket.java:589)
	at java.net.Socket.connect(Socket.java:538)
	at java.net.Socket.<init>(Socket.java:434)
	at java.net.Socket.<init>(Socket.java:211)
	at sun.rmi.transport.proxy.RMIDirectSocketFactory.createSocket(RMIDirectSocketFactory.java:40)
	at sun.rmi.transport.proxy.RMIMasterSocketFactory.createSocket(RMIMasterSocketFactory.java:148)
	at sun.rmi.transport.tcp.TCPEndpoint.newSocket(TCPEndpoint.java:613)
	... 45 more

于是修改hosts文件，将localhost的有关映射全部删除，重启IDEA后，maven正常工作了。