Clob，Blob，InputStream，byte 互转

一、byte[]=>Blob

我们可以通过Hibernate提供的表态方法来实现如：

org.hibernate.Hibernate.Hibernate.createBlob(new byte[1024]);

二、Blob=>byte[]

/**

* 把Blob类型转换为byte数组类型

* @param blob

* <a href="http://my.oschina.net/u/556800" target="_blank" rel="nofollow">@return</a>

*/

private byte[] blobToBytes(Blob blob) {

 

  BufferedInputStream is = null;

  try {

    is = new BufferedInputStream(blob.getBinaryStream());

    byte[] bytes = new byte[(int) blob.length()];

    int len = bytes.length;

    int offset = 0;

    int read = 0;

    while (offset < len && (read = is.read(bytes, offset, len offset)) >= 0) {

      offset += read;

    }

    return bytes;

  } catch (Exception e) {

    return null;

  } finally {

    try {

      is.close();

      is = null;

    } catch (IOException e) {

      return null;

    }

  }

}

三、InputStream=>byte[]

private byte[] InputStreamToByte(InputStream is) throws IOException { 

 

  ByteArrayOutputStream bytestream = new ByteArrayOutputStream(); 

  int ch; 

  while ((ch = is.read()) != -1) { 

    bytestream.write(ch); 

  } 

  byte imgdata[] = bytestream.toByteArray(); 

  bytestream.close(); 

 

  return imgdata; 

}

四、byte[]  => InputStream 

InputStream is = new ByteArrayInputStream(new byte[1024]);




五、InputStream => Blob


可通过Hibernate提供的API：


Hibernate.createBlob(new FileInputStream(" 可以为图片/文件等路径 "));





六、Blob => InputStream


Blog转流，可通过提供的API直接调用：


new Blob().getBinaryStream();





转：http://my.oschina.net/zimingforever/blog/81691