编写程序，拷贝一个带内容的文件夹

package com.heima.question8;import static org.junit.Assert.assertEquals;import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import org.junit.Test;/** * @author Alex Zhuang * */public class FileCopy {@Testpublic static void testCopyFolder(){String sourceFilePath="D:\\java_test";String targetFilePath="D:\\alex-test";copyFile(sourceFilePath , targetFilePath);System.out.println("Copy complete...");int sourceFileNum = new File(sourceFilePath).listFiles().length;int targetFileNum = new File(targetFilePath+ "\\"+new File(sourceFilePath).getName()).listFiles().length;assertEquals(sourceFileNum,targetFileNum);}@Testpublic static void testCopyFile(){String sourceFilePath="D:\\test1.txt";String targetFilePath="D:\\alex-test";copyFile(sourceFilePath , targetFilePath);System.out.println("Copy complete...");assertEquals(true,new File(targetFilePath+"\\"+new File(sourceFilePath).getName()).isFile());}/** * 如需测试，请先把”第8题测试“文件夹中的文件复制到D盘根目录 */public static void main(String[] args){testCopyFolder();testCopyFile();}/** * @param sourceFilePath 文件复制源 * @param targetFilePath 文件复制目标端 */public static void copyFile(String sourceFilePath , String targetFilePath){File sourceFile = new File(sourceFilePath);File[] sourceFiles = null;if(sourceFile.isDirectory()){targetFilePath +="\\"+sourceFile.getName();File targetFile = new File(targetFilePath);targetFile.mkdirs();sourceFiles = sourceFile.listFiles();}else if(sourceFile.isFile()){sourceFiles = new File[]{sourceFile};}for(int i=0;i<sourceFiles.length;i++){if(sourceFiles[i].isDirectory()){String newSourceFilePath= sourceFilePath + "\\"+sourceFiles[i].getName();copyFile(newSourceFilePath,targetFilePath);}else{try {FileInputStream fis = new FileInputStream(sourceFiles[i]);FileOutputStream fos = new FileOutputStream(targetFilePath+"\\"+sourceFiles[i].getName());int read = -1;while((read=fis.read())!=-1){fos.write(read);}fos.flush();fos.close();fis.close();} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}}}}