java zip

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.Enumeration;

import org.apache.tools.zip.ZipEntry;
import org.apache.tools.zip.ZipFile;
import org.apache.tools.zip.ZipOutputStream;

public class ZipUtils {
	static final int BUFFER = 1024;
	public static String encoding = "GBK";

	public static void zip(String inputFileName, String zipFileName)
			throws Exception {
		File f = new File(inputFileName);
		if(!f.exists())return;
		File zipFile = new File(zipFileName);
		ZipOutputStream out = new ZipOutputStream(new FileOutputStream(zipFile));
		out.setEncoding(encoding);
		zip(out, f, "");
		out.close();
	}

	private static void zip(ZipOutputStream out, File f, String base)
			throws Exception {
		if (f.isDirectory()) {
			File[] fl = f.listFiles();
			out.putNextEntry(new ZipEntry(base + "/"));
			base = base.length() == 0 ? "" : base + "/";
			for (int i = 0; i < fl.length; i++) {
				zip(out, fl[i], base + fl[i].getName());
			}
		} else {
			out.putNextEntry(new ZipEntry(base));
			FileInputStream in = new FileInputStream(f);
			int len;
			byte[] buf = new byte[BUFFER];
			try {
				while ((len = in.read(buf, 0, BUFFER)) != -1) {
					out.write(buf, 0, len);
				}
			} catch (Exception e) {
				e.printStackTrace();
			}finally{
				in.close();
			}
			
		}
	}

	public static void unZip(String fileName, String filePath) throws Exception{
		ZipFile zipFile = new ZipFile(fileName, encoding);
		Enumeration<?> emu = zipFile.getEntries();
		while (emu.hasMoreElements()) {
			ZipEntry entry = (ZipEntry) emu.nextElement();
			if (entry.isDirectory()) {
				new File(filePath + entry.getName()).mkdirs();
				continue;
			}
			File file = new File(filePath + entry.getName());
			File parent = file.getParentFile();
			if (parent != null && (!parent.exists())) {
				parent.mkdirs();
			}
			BufferedInputStream bis = null; 
			FileOutputStream fos = null;
			BufferedOutputStream bos = null;
			try {
				bis = new BufferedInputStream(zipFile
						.getInputStream(entry));
				fos = new FileOutputStream(file);
				bos = new BufferedOutputStream(fos, BUFFER);
				byte[] buf = new byte[BUFFER];
				int len = 0;
				while ((len = bis.read(buf, 0, BUFFER)) != -1) {
					fos.write(buf, 0, len);
				}
				bos.flush();
			} catch (Exception e) {
				e.printStackTrace();
			} finally{
				if(bos!=null){
					bos.close();
				}
				if(bis!=null){
					bis.close();
				}
			}
		}
		zipFile.close();
	}

	public static void main(String[] args) {

		try {
			ZipUtils.zip("d:/djfocus-models/", "d:/djfocus-models.zip");
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

}