java 把一个文件夹里图片复制到另一个文件夹里

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.Calendar;

public class SendServer {

private int num = 0;

public void process() {

Calendar calendar = Calendar.getInstance();
String dir = calendar.get(Calendar.YEAR) + "" + getTimeString(calendar.get(Calendar.MONTH) + "");

String oldPath = "/img2" + dir;
String newPath = "/img5" + dir;

try {

while(true){
System.out.println("复制 " + oldPath + " 目录开始");
long t1 = System.currentTimeMillis();

num = 0;
copyFolder(oldPath, newPath);

long t2 = System.currentTimeMillis();
System.out.println("复制目录结束，用时：" + (t2-t1) + "ms,共复制：" + num + "文件");
}

} catch (Exception ex) {
ex.printStackTrace();
}
}

public void copyFolder(String oldPath, String newPath) {

try {
File mFile = new File(newPath);
if(!mFile .exists()){
(new File(newPath)).mkdirs(); // 如果文件夹不存在 则建立新文件夹
}
File a = new File(oldPath);
String[] file = a.list();
File temp = null;
for (int i = 0; i < file.length; i++) {
if (oldPath.endsWith(File.separator)) {
temp = new File(oldPath + file[i]);
} else {
temp = new File(oldPath + File.separator + file[i]);
}

if (temp.isFile()) {
String fileName = newPath + "/" + (temp.getName()).toString();
File testFile = new File(fileName);
if (!testFile.exists()) {
FileInputStream input = new FileInputStream(temp);
FileOutputStream output = new FileOutputStream(fileName);
byte[] b = new byte[1024 * 5];
int len;
while ((len = input.read(b)) != -1) {
output.write(b, 0, len);
}
output.flush();
output.close();
input.close();
num++;
}
}
if (temp.isDirectory()) {// 如果是子文件夹
copyFolder(oldPath + "/" + file[i], newPath + "/" + file[i]);
}
}
} catch (Exception e) {
System.out.println("复制整个文件夹内容操作出错");
e.printStackTrace();

}
}

private String getTimeString(String time){
if(time.length()<2){
return "0" + time;
}
else{
return time;
}
}
}

public static class TreeNode {
/**节点名称**/
private String text;
/**节点路径**/
private String fileName;
/**子节点**/
private List<TreeNode> children = new ArrayList<TreeNode>();
}

public static TreeNode readfile(TreeNode tn){
try {

File file = new File(tn.fileName);
tn.text = file.getName();
if (!file.isDirectory()) {
//System.out.println(file.getName());

} else if (file.isDirectory()) {
String[] filelist = file.list();
for (int i = 0; i < filelist.length; i++) {
File readfile = new File(tn.fileName + "\\" + filelist[i]);
TreeNode tn1 = new TreeNode();
tn1.text = readfile.getName();
tn1.fileName = tn.fileName + "\\" + filelist[i];
if (!readfile.isDirectory()) {
tn.children.add(tn1);
} else if (readfile.isDirectory()) {
tn.children.add(readfile(tn1));
}
}
}

} catch (Exception e) {
System.out.println("readfile()   Exception:" + e.getMessage());
}
return tn;
}

public static void main(String[] args){
TreeNode tn = new TreeNode();
tn.fileName = "C:\\Users\\42955\\Desktop\\文件夹\\软件";
readfile(tn);
System.out.println(tn);
System.out.println(tn.text);
}