压缩字符

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

public class StringCompress
{

	// 压缩
	public static String compress(String str) throws IOException
	{
		if (str == null || str.length() == 0)
		{
			return str;
		}
		ByteArrayOutputStream out = new ByteArrayOutputStream();
		GZIPOutputStream gzip = new GZIPOutputStream(out);
		gzip.write(str.getBytes());
		gzip.close();
		return out.toString("ISO-8859-1");
	}

	// 解压缩
	public static String decompress(String str) throws IOException
	{
		if (str == null || str.length() == 0)
		{
			return str;
		}
		ByteArrayOutputStream out = new ByteArrayOutputStream();
		ByteArrayInputStream in = new ByteArrayInputStream(str
				.getBytes("ISO-8859-1"));
		GZIPInputStream gunzip = new GZIPInputStream(in);
		byte[] buffer = new byte[256];
		int n;
		while ((n = gunzip.read(buffer)) >= 0)
		{
			out.write(buffer, 0, n);
		}
		return out.toString("GBK");
	}


	public static void main(String[] args) throws IOException
	{
		
		
		
		sun.misc.BASE64Encoder encoder = new sun.misc.BASE64Encoder();
		sun.misc.BASE64Decoder decoder = new sun.misc.BASE64Decoder();
		
		String msg = "";
		System.out.println("压缩前长度：" + msg.length());
		
		//压缩
		String c = compress(msg);
		// 压缩后进行BASE64
		String base64data2 = encoder.encodeBuffer(c.getBytes("ISO-8859-1"));
		System.out.println("压缩后长度：" + base64data2.length());

		//解压前进行反BASE64
		byte[] b = decoder.decodeBuffer(base64data2);
		//解压
		String d = decompress(new String(b, "ISO-8859-1"));
		System.out.println("解压后长度：" + d.length());
		
	}

}