intellij (org.jdom.input.JDOMParseException) Error on line 1: 前言中不允许有内容。
参考：http://www.cnblogs.com/huangzp120/p/5003884.html
出现该异常的可能原因是：
idea异常关闭的情况。 我是因为电脑突然蓝屏了，重启后， 配置得重新配，然后编译的时候，就报这个错了。
异常信息：
Error:Internal error: (org.jdom.input.JDOMParseException) Error on line 1: 前言中不允许有内容。
org.jdom.input.JDOMParseException: Error on line 1: 前言中不允许有内容。
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:533)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:946)
at com.intellij.openapi.util.JDOMUtil.loadDocument(JDOMUtil.java:364)
at com.intellij.openapi.util.JDOMUtil.loadDocument(JDOMUtil.java:342)
at org.jetbrains.jps.model.serialization.JpsLoaderBase.tryLoadRootElement(JpsLoaderBase.java:99)
at org.jetbrains.jps.model.serialization.JpsLoaderBase.loadRootElement(JpsLoaderBase.java:72)
at org.jetbrains.jps.model.serialization.JpsLoaderBase.loadRootElement(JpsLoaderBase.java:43)
at org.jetbrains.jps.model.serialization.JpsLoaderBase.loadComponents(JpsLoaderBase.java:55)
at org.jetbrains.jps.model.serialization.JpsProjectLoader.loadFromDirectory(JpsProjectLoader.java:119)
at org.jetbrains.jps.model.serialization.JpsProjectLoader.loadProject(JpsProjectLoader.java:98)
at org.jetbrains.jps.model.serialization.impl.JpsSerializationManagerImpl.loadModel(JpsSerializationManagerImpl.java:41)
at org.jetbrains.jps.cmdline.JpsModelLoaderImpl.loadModel(JpsModelLoaderImpl.java:45)
at org.jetbrains.jps.cmdline.BuildRunner.load(BuildRunner.java:78)
at org.jetbrains.jps.cmdline.BuildSession.runBuild(BuildSession.java:261)
at org.jetbrains.jps.cmdline.BuildSession.run(BuildSession.java:124)
at org.jetbrains.jps.cmdline.BuildMain$MyMessageHandler$1.run(BuildMain.java:238)
at org.jetbrains.jps.service.impl.SharedThreadPoolImpl$1.run(SharedThreadPoolImpl.java:41)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; 前言中不允许有内容。
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:198)
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.fatalError(ErrorHandlerWrapper.java:177)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:441)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:368)
at com.sun.org.apache.xerces.internal.impl.XMLScanner.reportFatalError(XMLScanner.java:1436)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(XMLDocumentScannerImpl.java:999)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:606)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:117)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:510)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:848)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:777)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:141)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1213)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:648)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:518)
... 21 more
Caused by: org.xml.sax.SAXParseException; lineNumber: 1; columnNumber: 1; 前言中不允许有内容。
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.createSAXParseException(ErrorHandlerWrapper.java:198)
at com.sun.org.apache.xerces.internal.util.ErrorHandlerWrapper.fatalError(ErrorHandlerWrapper.java:177)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:441)
at com.sun.org.apache.xerces.internal.impl.XMLErrorReporter.reportError(XMLErrorReporter.java:368)
at com.sun.org.apache.xerces.internal.impl.XMLScanner.reportFatalError(XMLScanner.java:1436)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl$PrologDriver.next(XMLDocumentScannerImpl.java:999)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:606)
at com.sun.org.apache.xerces.internal.impl.XMLNSDocumentScannerImpl.next(XMLNSDocumentScannerImpl.java:117)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:510)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:848)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:777)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:141)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1213)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:648)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:518)
at org.jdom.input.SAXBuilder.build(SAXBuilder.java:946)
at com.intellij.openapi.util.JDOMUtil.loadDocument(JDOMUtil.java:364)
at com.intellij.openapi.util.JDOMUtil.loadDocument(JDOMUtil.java:342)
at org.jetbrains.jps.model.serialization.JpsLoaderBase.tryLoadRootElement(JpsLoaderBase.java:99)
at org.jetbrains.jps.model.serialization.JpsLoaderBase.loadRootElement(JpsLoaderBase.java:72)
at org.jetbrains.jps.model.serialization.JpsLoaderBase.loadRootElement(JpsLoaderBase.java:43)
at org.jetbrains.jps.model.serialization.JpsLoaderBase.loadComponents(JpsLoaderBase.java:55)
at org.jetbrains.jps.model.serialization.JpsProjectLoader.loadFromDirectory(JpsProjectLoader.java:119)
at org.jetbrains.jps.model.serialization.JpsProjectLoader.loadProject(JpsProjectLoader.java:98)
at org.jetbrains.jps.model.serialization.impl.JpsSerializationManagerImpl.loadModel(JpsSerializationManagerImpl.java:41)
at org.jetbrains.jps.cmdline.JpsModelLoaderImpl.loadModel(JpsModelLoaderImpl.java:45)
at org.jetbrains.jps.cmdline.BuildRunner.load(BuildRunner.java:78)
at org.jetbrains.jps.cmdline.BuildSession.runBuild(BuildSession.java:261)
at org.jetbrains.jps.cmdline.BuildSession.run(BuildSession.java:124)
at org.jetbrains.jps.cmdline.BuildMain$MyMessageHandler$1.run(BuildMain.java:238)
at org.jetbrains.jps.service.impl.SharedThreadPoolImpl$1.run(SharedThreadPoolImpl.java:41)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask.run(FutureTask.java:262)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)
方法1：
删除 C:\Users\用户名\.IntelliJIdea14\system\caches里的全部文件。
方法2：
方法1未解决时，
In project/.idea I have broken workspace.xml file. I just close Android Studio (Intellij IDEA), remove this file and start Android Studio.
All other approaches not work for me.
即删除项目文件夹里面的.idea/workspace.xml 后，发现竟然可以运行了。
删除之前 我还特地查看了workspace.xml 这个文件 ， 变成 了 一些字节码的文件 了。。不是正常的xml文件 。