字符串压缩

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;
import java.util.zip.ZipOutputStream;

import sun.misc.BASE64Decoder;

public class StringCompression {
	public static final byte[] compress(String str) {
		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("0"));
			zout.write(str.getBytes());
			zout.closeEntry();
			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;
	}