压缩并且保存到磁盘上

代码自己学习用~....

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;

import sun.misc.BASE64Encoder;

public class ZipUtil {

	public static final byte[] compress(String str, String fileName) {
		if (str == null)
			return null;
		byte[] compressed;
		ByteArrayOutputStream out = null;
		ZipOutputStream zout = null;
		try {
			out = new ByteArrayOutputStream();
			zout = new ZipOutputStream(out);
			zout.putNextEntry(new ZipEntry(fileName));
			zout.write(str.getBytes());
			zout.closeEntry();
			zout.finish();
			compressed = out.toByteArray();
		} catch (IOException e) {
			compressed = null;
		} finally {
			if (zout != null) {
				try {
					zout.close();
				} catch (IOException e) {
				}
			}
			if (out != null) {
				try {
					out.close();
				} catch (IOException e) {
				}
			}
		}
		return compressed;
	}

	/**
	 * 将压缩后的 byte[] 数据解压缩
	 * 
	 * @param compressed
	 *            压缩后的 byte[] 数据
	 * @return 解压后的字符串
	 */
	public static final String decompress(byte[] compressed) {
		if (compressed == null)
			return null;
		ByteArrayOutputStream out = null;
		ByteArrayInputStream in = null;
		ZipInputStream zin = null;
		String decompressed;
		try {
			out = new ByteArrayOutputStream();
			in = new ByteArrayInputStream(compressed);
			zin = new ZipInputStream(in);
			ZipEntry entry = zin.getNextEntry();
			byte[] buffer = new byte[1024];
			int offset = -1;
			while ((offset = zin.read(buffer)) != -1) {
				out.write(buffer, 0, offset);
			}
			decompressed = out.toString();
		} catch (IOException e) {
			decompressed = null;
		} finally {
			if (zin != null) {
				try {
					zin.close();
				} catch (IOException e) {
				}
			}
			if (in != null) {
				try {
					in.close();
				} catch (IOException e) {
				}
			}
			if (out != null) {
				try {
					out.close();
				} catch (IOException e) {
				}
			}
		}
		return decompressed;
	}
	
	public static void testSaveZip(byte[] b, String fileName) throws IOException {
		String outFilename = "c:\\"+fileName+".zip";  
		byte[] buf = new byte[1024];
		FileOutputStream out = new FileOutputStream(outFilename);
		ByteArrayInputStream fos=new ByteArrayInputStream(b);
		int len = -1;
		while ((len = fos.read(buf))!=-1)
		out.write(buf, 0, len);
		out.close();
	}
	
	public static void main(String[] args) {
		String testStr = "测试，zip!";
		byte[] b = compress(testStr, "data");
		BASE64Encoder enc=new BASE64Encoder();
		System.out.println(enc.encode(b));
		String deCompress = decompress(b);
		System.out.println("--------------------------------------------");
		System.out.println(deCompress);
		try {
			testSaveZip(b,"data");
		} catch (IOException e) {
			e.printStackTrace();
		}
	}

}