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

public class ReNameFile {

	private static final String PATH = "D:/shane/";
	private static final String TMP_PATH = PATH + "/tmp";

	/**
	 * @param args
	 * @throws Exception
	 */
	public static void main(String[] args) throws Exception {

		File file = new File(PATH);
		String[] names = file.list();

		for (int i = 0; i < names.length; i++) {
			System.out.println("name: " + names[i]);
		}
		new File(TMP_PATH).mkdir();

		// 方式一：原始檔不存在了。
		// for (int i = 0; i < names.length; i++) {
		// new File(PATH + "/" + names[i]).renameTo(new File(TMP_PATH + "/"
		// + (i + 1) + ".png"));
		// }

		// 方式二：原始檔存在。
		for (int i = 0; i < names.length; i++) {

			FileInputStream is = new FileInputStream(new File(PATH + "/"
					+ names[i]));
			FileOutputStream os = new FileOutputStream(new File(TMP_PATH + "/"
					+ (i + 1) + ".png"));

			byte[] buf = new byte[1024];

			while (is.read(buf) != -1) {
				os.write(buf);
			}

		}

	}
}