解决问题：com.alibaba.excel.exception.ExcelAnalysisException: Can not instance class: xx.xx.xx

红太狼 2021-01-24 03:47 8972阅读 1赞

com.alibaba.excel.exception.ExcelAnalysisException: Can not instance class: com.atguigu.demo.excel.DemoData
    
    	at com.alibaba.excel.read.metadata.holder.AbstractReadHolder.notifyEndOneRow(AbstractReadHolder.java:147)
    	at com.alibaba.excel.analysis.v07.handlers.ProcessResultCellHandler.endHandle(ProcessResultCellHandler.java:44)
    	at com.alibaba.excel.analysis.v07.XlsxRowHandler.endElement(XlsxRowHandler.java:44)
    	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.endElement(AbstractSAXParser.java:609)
    	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanEndElement(XMLDocumentFragmentScannerImpl.java:1782)
    	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(XMLDocumentFragmentScannerImpl.java:2967)
    	at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(XMLDocumentScannerImpl.java:602)
    	at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(XMLDocumentFragmentScannerImpl.java:505)
    	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:842)
    	at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(XML11Configuration.java:771)
    	at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(XMLParser.java:141)
    	at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(AbstractSAXParser.java:1213)
    	at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(SAXParserImpl.java:643)
    	at com.alibaba.excel.analysis.v07.XlsxSaxAnalyser.parseXmlSource(XlsxSaxAnalyser.java:158)
    	at com.alibaba.excel.analysis.v07.XlsxSaxAnalyser.execute(XlsxSaxAnalyser.java:182)
    	at com.alibaba.excel.analysis.ExcelAnalyserImpl.analysis(ExcelAnalyserImpl.java:105)
    	at com.alibaba.excel.ExcelReader.read(ExcelReader.java:180)
    	at com.alibaba.excel.ExcelReader.read(ExcelReader.java:170)
    	at com.alibaba.excel.read.builder.ExcelReaderSheetBuilder.doRead(ExcelReaderSheetBuilder.java:160)
    	at com.atguigu.demo.excel.TestEasyexcel.testread(TestEasyexcel.java:33)
    	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 org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
    	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
    	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    	at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
    	at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:230)
    	at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:58)
    Caused by: com.alibaba.excel.exception.ExcelDataConvertException: Can not instance class: com.atguigu.demo.excel.DemoData
    	at com.alibaba.excel.read.listener.ModelBuildEventListener.buildUserModel(ModelBuildEventListener.java:98)
    	at com.alibaba.excel.read.listener.ModelBuildEventListener.invoke(ModelBuildEventListener.java:38)
    	at com.alibaba.excel.read.listener.ModelBuildEventListener.invoke(ModelBuildEventListener.java:28)
    	at com.alibaba.excel.read.metadata.holder.AbstractReadHolder.notifyEndOneRow(AbstractReadHolder.java:141)
    	... 41 more
    Caused by: java.lang.InstantiationException: com.atguigu.demo.excel.DemoData
    	at java.lang.Class.newInstance(Class.java:427)
    	at com.alibaba.excel.read.listener.ModelBuildEventListener.buildUserModel(ModelBuildEventListener.java:94)
    	... 44 more
    Caused by: java.lang.NoSuchMethodException: com.atguigu.demo.excel.DemoData.<init>()
    	at java.lang.Class.getConstructor0(Class.java:3082)
    	at java.lang.Class.newInstance(Class.java:412)
    	... 45 more

*  问题描述：在使用easyExcel时，进行读操作，出现如上错误。
 *  解决思考：
    
     *  分析：在上述报错信息中，我们关注下面四句输出信息

ExcelAnalysisException: Can not instance class: com.atguigu.demo.excel.DemoData
    ExcelDataConvertException: Can not instance class: com.atguigu.demo.excel.DemoData
    InstantiationException: com.atguigu.demo.excel.DemoData
    NoSuchMethodException: com.atguigu.demo.excel.DemoData.<init>()

1.  四句话都有DemoData，不难分析出来该类有问题
2.  其次， Can not instance class，不能实例化，可以推出构造方法有问题
3.  最后一句：NoSuchMethodException没有此方法，得出缺少无参构造方法
4.  定位到该类，发现确实没有无参构造

@Data
    @AllArgsConstructor
    public class DemoData {

*  **解决方法**：

添加无参构造：例如  
加上该注解@NoArgsConstructor

@Data
    @AllArgsConstructor
    @NoArgsConstructor
    public class DemoData {

或者自己写上无参构造

public DemoData(){ }