我在Oracle 11G（11.1）中有一个表，其中包含一个包含XML文档的BLOB列 .

XML文档已使用java程序写入表中，并已使用java.util.zip deflator进行序列化和压缩 .

有没有一种简单的方法来使用SQL或PLSQL提取此文档来反转用于创建BLOB列以获取原始XML文档的过程？

我从Web应用程序中识别出一段java，它读取的列看起来像下面的代码，但出于支持目的，希望能够从后端访问列数据 .

private IntegrationStagingDataBean fromObjectToBean(StagedMessage message) throws ServerException {
    IntegrationStagingDataBean bean = new IntegrationStagingDataBean();
    bean.setBusinessId(message.getBusinessId());
    bean.setBusinessType(message.getBusinessType());
    bean.setCreateTime(message.getCreateTime());
    bean.setDeleted(message.hasBeenDeleted() ? "Y" : "N");
    bean.setErrorMessage(message.getErrorMessage());
    bean.setId(message.getId());
    bean.setStoreId(message.getStoreId());
    bean.setMessageDirection(message.getMessageDirection().getDbCode());
    bean.setMessageFamily(message.getMessageFamily().getDbCode());
    bean.setMessageType(message.getMessageType().getDbCode());
    bean.setProcessed(message.hasBeenProcessed() ? "Y" : "N");
    bean.setRetryCount(message.getRetryCount());
    bean.setUpdateTime(message.getUpdateTime());
    try {
        bean.setSerializedDeo(ObjectUtils.toByteArray(new CompressedObject(message.getDeo())));
    } catch (IOException ioex) {
        throw new ServerException("Problem setting compressed serialized object", ioex);
    }
    return bean;
}

private StagedMessage fromBeanToObject(IntegrationStagingDataBean bean) throws ServerException {
    DataExchangeObject deo = null;
    Blob blob = (Blob) bean.getSerializedDeo();
    try {
        CompressedObject compressedObject = (CompressedObject) new              
              ObjectInputStream(blob.getBinaryStream()).readObject();
        deo = (DataExchangeObject) compressedObject.recoverObject();
    } catch (Exception e) {
        throw new ServerException("Couldn't uncompress/deserialize DEO from BLOB", e);
    }

并发现以下附加功能分布在少数几个包中，表明它正在使用java.util.zip . *中的java函数deflater .

public CompressedObject（Object object）抛出IOException {dataToSend = null; if（object！= null）dataToSend = ObjectUtils.toCompressedByteArray（object）; }

public static final byte[] toCompressedByteArray(Object o)
    throws IOException
{
    return compressByteArray(toByteArray(o));
}

public static final byte[] compressByteArray(byte input[])
{
    Deflater compressor = new Deflater(9);
    compressor.setInput(input);
    compressor.finish();
    ByteArrayOutputStream bos = new ByteArrayOutputStream(input.length);
    byte buf[] = new byte[1024];
    int count;
    for(; !compressor.finished(); bos.write(buf, 0, count))
        count = compressor.deflate(buf);

    try
    {
        bos.close();
    }
    catch(IOException e) { }
    return bos.toByteArray();
}

public static final byte[] decompressByteArray(byte arr[])
{
    Inflater decompressor = new Inflater();
    decompressor.setInput(arr);
    ByteArrayOutputStream bos = new ByteArrayOutputStream(arr.length);
    byte buf[] = new byte[1024];
    while(!decompressor.finished()) 
        try
        {
            int count = decompressor.inflate(buf);
            bos.write(buf, 0, count);
        }
        catch(DataFormatException e) { }
    try
    {
        bos.close();
    }
    catch(IOException e) { }
    return bos.toByteArray();
}

提前致谢 .

oracle blob compression