将压缩并Base64后的字符串进行解密解压

/** 
     * 将字符串压缩后Base64 
     * @param primStr 待加压加密函数 
     * @return 
     */  
    public static String zipString(String primStr) {  
        if (primStr == null || primStr.length() == 0) {  
            return primStr;  
        }  
        ByteArrayOutputStream out = null;    
        ZipOutputStream zout = null;    
        try{    
            out = new ByteArrayOutputStream();    
            zout = new ZipOutputStream(out);    
            zout.putNextEntry(new ZipEntry("0"));  
            zout.write(primStr.getBytes(Constants.transfer_charset));    
            zout.closeEntry();  
            return new BASE64Encoder().encode(out.toByteArray());  
        } catch (IOException e) {  
            log.error("对字符串进行加压加密操做失败：", e);  
            return null;  
        } finally {  
            if (zout != null) {  
                try {  
                    zout.close();  
                } catch (IOException e) {  
                    log.error("对字符串进行加压加密操做，关闭zip操做流失败：", e);  
                }  
            }  
        }  
    }  

/*
 * 将压缩并Base64后的字符串进行解密解压
 * @param compressedStr 待解密解压字符串
 * @return
 */
public static final String unzipString(String compressedStr) {
    if (compressedStr == null) {
        return null;
    }
    ByteArrayOutputStream out = null;
    ByteArrayInputStream in = null;
    ZipInputStream zin = null;
    String decompressed = null;
    try {
        byte[] compressed = new BASE64Decoder().decodeBuffer(compressedStr);
        out = new ByteArrayOutputStream();
        in = new ByteArrayInputStream(compressed);
        zin = new ZipInputStream(in);
        zin.getNextEntry();
        byte[] buffer = new byte[1024];
        int offset = -1;
        while((offset = zin.read(buffer)) != -1) {
            out.write(buffer, 0, offset);
        }
        decompressed = out.toString("gbk");
    } catch (IOException e) {
        log.error("对字符串进行解密解压操做失败：", e);
        decompressed = null;
    } finally {
        if (zin != null) {
            try {
                zin.close();
            } catch (IOException e) {
                log.error("对字符串进行解密解压操做，关闭压缩流失败：", e);
            }
        }
        if (in != null) {
            try {
                in.close();
            } catch (IOException e) {
                log.error("对字符串进行解密解压操做，关闭输入流失败：", e);
            }
        }
        if (out != null) {
            try {
                out.close();
            } catch (IOException e) {
                log.error("对字符串进行解密解压操做，关闭输出流失败：", e);
            }
        }
    }
    return decompressed;
}