Uncertain behaviour of appium script with TestNG

My Script is in working conditions few days before but now it has displayed the following error . But this script working while creating new java project into eclipse. Need help for uncertain issue

org.testng.TestNGException:
Cannot find class in classpath: example.HannaTestScript
at org.testng.xml.XmlClass.loadClass(XmlClass.java:81)
at org.testng.xml.XmlClass.init(XmlClass.java:73)
at org.testng.xml.XmlClass.(XmlClass.java:59)
at org.testng.xml.TestNGContentHandler.startElement(TestNGContentHandler.java:546)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.startElement(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.AbstractXMLDocumentParser.emptyElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.dtd.XMLDTDValidator.emptyElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanStartElement(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl$FragmentContentDriver.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentScannerImpl.next(Unknown Source)
at com.sun.org.apache.xerces.internal.impl.XMLDocumentFragmentScannerImpl.scanDocument(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XML11Configuration.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.XMLParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.parsers.AbstractSAXParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl$JAXPSAXParser.parse(Unknown Source)
at com.sun.org.apache.xerces.internal.jaxp.SAXParserImpl.parse(Unknown Source)
at javax.xml.parsers.SAXParser.parse(Unknown Source)
at org.testng.xml.XMLParser.parse(XMLParser.java:38)
at org.testng.xml.SuiteXmlParser.parse(SuiteXmlParser.java:16)
at org.testng.xml.SuiteXmlParser.parse(SuiteXmlParser.java:9)
at org.testng.xml.Parser.parse(Parser.java:172)
at org.testng.TestNG.initializeSuitesAndJarFile(TestNG.java:300)
at org.testng.remote.AbstractRemoteTestNG.run(AbstractRemoteTestNG.java:103)
at org.testng.remote.RemoteTestNG.initAndRun(RemoteTestNG.java:152)
at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:57)

Hello,

I have the same problem in Android Studio 3.0. Any solution?

Thank you very much.

The solution is write to the Android Studio terminal:
gradlew test