Add ExcelUtilsTest.java , the unit test for ExcelUtils (#1500)

     */

    public static void genExcelFile(String content,String title,String xlsFilePath){

        List<LinkedHashMap> itemsList;

        try {

        //The JSONUtils.toList has been try catch ex

        itemsList = JSONUtils.toList(content, LinkedHashMap.class);

        }catch (Exception e){

            logger.error(String.format("json format incorrect : %s",content),e);

            throw new RuntimeException("json format incorrect",e);

        }

        if (itemsList == null || itemsList.size() == 0){

            logger.error("itemsList is null");

/*

 * Licensed to the Apache Software Foundation (ASF) under one or more

 * contributor license agreements.  See the NOTICE file distributed with

 * this work for additional information regarding copyright ownership.

 * The ASF licenses this file to You under the Apache License, Version 2.0

 * (the "License"); you may not use this file except in compliance with

 * the License.  You may obtain a copy of the License at

 *

 *    http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 */

package org.apache.dolphinscheduler.alert.utils;

import org.junit.After;

import org.junit.Before;

import org.junit.Rule;

import org.junit.Test;

import org.junit.rules.ExpectedException;

import org.junit.rules.TemporaryFolder;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import java.io.File;

import static org.junit.Assert.assertTrue;

public class ExcelUtilsTest {

    private static final Logger logger = LoggerFactory.getLogger(ExcelUtilsTest.class);

    @Rule

    public ExpectedException expectedException = ExpectedException.none();

    @Rule

    public TemporaryFolder folder = new TemporaryFolder();

    private String rootPath = null;

    @Before

    public void setUp() throws Exception {

        folder.create();

        rootPath = folder.getRoot().getAbsolutePath();

    }

    @After

    public void tearDown() throws Exception {

        folder.delete();

    }

    /**

     * Test GenExcelFile

     */

    @Test

    public void testGenExcelFile() {

        //Define dest file path

        String xlsFilePath = rootPath + System.getProperty("file.separator");

        logger.info("xlsFilePath: "+xlsFilePath);

        //Define correctContent

        String correctContent = "[{\"name\":\"ds name\",\"value\":\"ds value\"}]";

        //Define incorrectContent

        String incorrectContent1 = "{\"name\":\"ds name\",\"value\":\"ds value\"}";

        //Define title

        String title = "test report";

        //Invoke genExcelFile with correctContent

        ExcelUtils.genExcelFile(correctContent, title, xlsFilePath);

        //Test file exists

        File xlsFile = new File(xlsFilePath + Constants.SINGLE_SLASH + title + Constants.EXCEL_SUFFIX_XLS);

        assertTrue(xlsFile.exists());

        //Expected RuntimeException

        expectedException.expect(RuntimeException.class);

        //Expected error message

        expectedException.expectMessage("itemsList is null");

        //Invoke genExcelFile with incorrectContent, will cause RuntimeException

        ExcelUtils.genExcelFile(incorrectContent1, title, xlsFilePath);

    }

}

 No newline at end of file

						<include>**/common/graph/*.java</include>

						<include>**/api/utils/CheckUtilsTest.java</include>

						<include>**/api/utils/FileUtilsTest.java</include>

            <include>**/alert/utils/ExcelUtilsTest.java</include>

					</includes>

					<!-- <skip>true</skip> -->

				</configuration>