文件工具类

废话不说直接上代码：

package cn.java.sys.common.util;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.UUID;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;

/**
 * 文件类
 * 
 * @author java
 * 
 */
public abstract class FileUtil {

	/**
	 * 删除文件夹(里面的文件一并删除)
	 * 
	 * @param folderPath
	 */
	public static void delFolder(String folderPath) {
		try {
			delAllFile(folderPath); // 删除完里面所有内容
			String filePath = folderPath;
			filePath = filePath.toString();
			java.io.File myFilePath = new java.io.File(filePath);
			myFilePath.delete(); // 删除空文件夹
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	/**
	 * 删除全部文件
	 * 
	 * @param path
	 * @return
	 */
	private static boolean delAllFile(String path) {
		boolean flag = false;
		File file = new File(path);
		if (!file.exists()) {
			return flag;
		}

		if (!file.isDirectory()) {
			return flag;
		}

		String[] tempList = file.list();

		File temp = null;
		for (int i = 0; i < tempList.length; i++) {
			if (path.endsWith(File.separator)) {
				temp = new File(path + tempList[i]);
			} else {
				temp = new File(path + File.separator + tempList[i]);
			}
			if (temp.isFile() && temp.exists()) {
				deleteFile(temp);
			}
			if (temp.isDirectory()) {
				delAllFile(path + "/" + tempList[i]);
				delFolder(path + "/" + tempList[i]);
				flag = true;
			}
		}
		return flag;
	}

	public static void deleteFile(String path) {
		File file = new File(path);
		deleteFile(file);
	}

	/**
	 * 删除某个文件，若删除不成功，尝试十次
	 * 
	 * @param file
	 */
	public static void deleteFile(File file) {
		if (file.isFile() && file.exists()) {
			int tryCount = 0;
			boolean result = false;
			while (!result && tryCount++ < 10) {
				System.gc();
				result = file.delete();
			}
		}
	}

	// 获取文件的扩展名
	public static String getExtension(String fileName) {
		if (fileName != null && fileName.length() > 0) {
			int i = fileName.lastIndexOf(".");
			if (i > -1 && i < (fileName.length() - 1)) {
				return fileName.substring(i + 1);
			}
		}
		return "";
	}
	/**
	 * 
	 * @param filePath 需要导出文件的路径
	 * @param response 
	 * @return 0 失败；1 成功
	 */
	public static int downLoadFile(String filePath,HttpServletResponse response){
		try {
			String fileName = "";
			if (filePath.lastIndexOf("/") > 0) {
				fileName = new String(filePath.substring(
						filePath.lastIndexOf("/") + 1, filePath.length()));
			} else if (filePath.lastIndexOf("\\") > 0) {
				fileName = new String(filePath.substring(
						filePath.lastIndexOf("\\") + 1, filePath.length()));
			}

			File file = new File(filePath);
			if (file.exists()) {
				FileInputStream fis = new FileInputStream(file);

				response.setContentType("application/octet-stream");
				response.setHeader("Content-Disposition", "attachment; filename="
						+ java.net.URLEncoder.encode(fileName, "utf-8"));
				response.setContentLength((int) file.length());

				ServletOutputStream out = response.getOutputStream();
				byte[] buffer = new byte[1024];
				int temp;
				while ((temp = fis.read(buffer, 0, 1024)) > 0) {
					out.write(buffer, 0, temp);
				}
				fis.close();
				return 1;
			}
		} catch (Exception e) {
			e.printStackTrace();
		}
		return 0;
	}
	
	public static void downLoadFile(String fileName,String path ,HttpServletResponse response) throws IOException{
		File file = new File(path);
		if (file.exists()) {
			FileInputStream fis = new FileInputStream(file);

			response.setContentType("application/octet-stream");
			response.setHeader("Content-Disposition", "attachment; filename="
					+ java.net.URLEncoder.encode(fileName, "utf-8"));
			response.setContentLength((int) file.length());

			ServletOutputStream out = response.getOutputStream();
			byte[] buffer = new byte[1024];
			int temp;
			while ((temp = fis.read(buffer, 0, 1024)) > 0) {
				out.write(buffer, 0, temp);
			}
			fis.close();
		}
		
	}
	public static void main(String[] args) {
		System.out.println(File.separator+FileUtil.getExtension("1.gif"));
		System.out.println(UUID.randomUUID().toString());
	}

	public String getFileEndName(String fileName) {
		int i = fileName.lastIndexOf(". ");
		String endName = "";
		endName = fileName.substring(i + 1);
		return endName;
	}
	
	/**
	 * 获取文件名，去掉文件后缀
	 * @param fileName 全文件名
	 * @return
	 */
	public static String getFileName(String fileName){
		if (fileName != null && fileName.length() > 0) {
			int i = fileName.lastIndexOf(".");
			if (i > -1 && i < (fileName.length() - 1)) {
				String s = fileName.substring(0, i);
				return s;
			}
		}
		return "";
	}
	/**
	 * 压缩文件
	 * @param response
	 * @param path 文件路径
	 * @throws Exception 
	 */
	public static void compressFile(HttpServletResponse response,String path) throws Exception{
		response.setContentType("application/octet-stream");
		response.setHeader("Content-Disposition", "attachment; filename="
				+ java.net.URLEncoder.encode("picture.zip", "utf-8"));
		
		
	}
}