Report Generate Module 20

HI Team,

When I run test case through command prompt, as mvn test
code running successfully but report is not generated. It shows null under Target-->Report folder

Below is my customlistner class file
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package com.testing.framework.DDF;
import com.testing.framework.DDF.util.ErrorUtil;
import java.io.File;



import java.io.IOException;
import java.util.ArrayList;
import java.util.Date;
import java.util.Hashtable;
import java.util.List;

import org.apache.commons.io.FileUtils;
import org.testng.IInvokedMethod;
import org.testng.IInvokedMethodListener;
import org.testng.ISuite;
import org.testng.ISuiteListener;
import org.testng.ITestResult;
import org.testng.Reporter;
import org.testng.TestListenerAdapter;
import org.testng.internal.Utils;

import com.testing.framework.DDF.util.Constants;
import com.testing.framework.DDF.util.Xls_Reader;



public class CustomListener extends TestListenerAdapter implements IInvokedMethodListener,ISuiteListener{

public static Hashtable<String, String> resultTable;
public static ArrayList<String> keys;
public static String resultFolderName;
public static String resultFilePath;
public static Xls_Reader xls;


public void onTestFailure(ITestResult tr){
// report(tr.getName(), tr.getThrowable().getMessage());

List<Throwable> verificationFailures = ErrorUtil.getVerificationFailures();
String errMsg="";
for(int i=0;i<verificationFailures.size();i++){
errMsg=errMsg+"["+verificationFailures.get(i).getMessage()+"]-";
}
report(tr.getName(), errMsg);

}

public void onTestSkipped(ITestResult tr) {
report(tr.getName(), tr.getThrowable().getMessage());


}

public void onTestSuccess(ITestResult tr){
report(tr.getName(), "PASS");

}

public void afterInvocation(IInvokedMethod method, ITestResult result) {

Reporter.setCurrentTestResult(result);

if (method.isTestMethod()) {
List<Throwable> verificationFailures = ErrorUtil.getVerificationFailures();
//if there are verification failures...
if (verificationFailures.size() != 0) {
//set the test to failed
result.setStatus(ITestResult.FAILURE);

//if there is an assertion failure add it to verificationFailures
if (result.getThrowable() != null) {
verificationFailures.add(result.getThrowable());
}

int size = verificationFailures.size();
//if there's only one failure just set that
if (size == 1) {
result.setThrowable(verificationFailures.get(0));
} else {
//create a failure message with all failures and stack traces (except last failure)
StringBuffer failureMessage = new StringBuffer("Multiple failures (").append(size).append("):nn");
for (int i = 0; i < size-1; i++) {
failureMessage.append("Failure ").append(i+1).append(" of ").append(size).append(":n");
Throwable t = verificationFailures.get(i);
String fullStackTrace = Utils.stackTrace(t, false)[1];
failureMessage.append(fullStackTrace).append("nn");
}

//final failure
Throwable last = verificationFailures.get(size-1);
failureMessage.append("Failure ").append(size).append(" of ").append(size).append(":n");
failureMessage.append(last.toString());

//set merged throwable
Throwable merged = new Throwable(failureMessage.toString());
merged.setStackTrace(last.getStackTrace());

result.setThrowable(merged);

}
}

}


}

public void beforeInvocation(IInvokedMethod arg0, ITestResult test)
{
}


@Override
public void onStart(ISuite suite) {
System.out.println("Starting suite "+ suite.getName());
if(resultTable==null){
keys = new ArrayList<String>();
resultTable = new Hashtable<String,String>();
}

if(resultFolderName==null){// first Suite
Date d = new Date();
resultFolderName=d.toString().replace(":", "_");
File f = new File(System.getProperty("user.dir")+"//target//reports//"+resultFolderName);
f.mkdir();
// change
resultFilePath=System.getProperty("user.dir")+"//target//reports//"+resultFolderName+"//Report.xlsx";
File src = new File(System.getProperty("user.dir")+"//target//reports//ReportTemplate.xlsx");
File dest = new File(resultFilePath);
try {
FileUtils.copyFile(src, dest);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}


@Override
public void onFinish(ISuite suite) {
if(resultTable !=null){
System.out.println("Finishing suite "+ suite.getName());
System.out.println(resultTable);
System.out.println(keys);

// write results in xlsx
if(!suite.getName().equals(Constants.ROOT_SUITE)){
Xls_Reader xls = new Xls_Reader(resultFilePath);
xls.addSheet(suite.getName());
// add the results in the sheet

// create col Names
xls.setCellData(suite.getName(), 0, 1, "Test Case");
xls.setCellData(suite.getName(), 1, 1, "Result");

for(int i=0;i<keys.size();i++){
String key = keys.get(i);
String result = resultTable.get(key);
xls.setCellData(suite.getName(), 0, i+2, key);
xls.setCellData(suite.getName(), 1, i+2, result);

}

}

resultTable=null;
keys=null;
}

}

public void report(String name,String result){
// test Iteration 1
// test Iteration 2
int iteration_number=1;
while(resultTable.containsKey(name+" Iteration "+iteration_number)){
iteration_number++;
}
keys.add(name+" Iteration "+iteration_number);
resultTable.put(name+" Iteration "+iteration_number, result);

}

}