解压snappy压缩文件

使用C++ Lib解压缩

在snappy页面下载Lib，执行Snappy.Uncompress方法解压。

使用Java Lib解压缩

下载xerial snappy-java，使用Snappy.Uncompress或Snappy.SnappyInputStream解压缩，不支持SnappyFramedInputStream。

<dependency>
<groupId>org.xerial.snappy</groupId>
<artifactId>snappy-java</artifactId>
<version>1.0.4.1</version>
<type>jar</type>
<scope>compile</scope>
</dependency>

• Snappy.Uncompress

  String fileName = "C:\\我的下载\\36_1474212963188600684_4451886.snappy";
  RandomAccessFile randomFile = new RandomAccessFile(fileName, "r");
  int fileLength = (int) randomFile.length();
  randomFile.seek(0);
  byte[] bytes = new byte[fileLength];
  int byteread = randomFile.read(bytes);
  System.out.println(fileLength);
  System.out.println(byteread);
  byte[] uncompressed = Snappy.uncompress(bytes);
  String result = new String(uncompressed, "UTF-8");
  System.out.println(result);

• Snappy.SnappyInputStream

  String fileName = "C:\\我的下载\\36_1474212963188600684_4451886.snappy";
  SnappyInputStream sis = new SnappyInputStream(new FileInputStream(fileName));
  byte[] buffer = new byte[4096];
  int len = 0;
  while ((len = sis.read(buffer)) != -1) {
      System.out.println(new String(buffer, 0, len));
  }

使用Python Lib解压缩

1. 下载并安装Python压缩库。
2. 执行解压代码。
   解压缩代码示例如下：

   import snappy
   compressed = open('/tmp/temp.snappy').read()
   snappy.uncompress(compressed)
                               

   说明 不支持通过以下命令行工具解压snappy压缩文件，命令行模式下仅支持hadoop模式（hadoop_stream_decompress）与流模式（stream_decompress）。

   $ python -m snappy -c uncompressed_file compressed_file.snappy
   $ python -m snappy -d compressed_file.snappy uncompressed_file                            

使用Linux环境解压工具解压缩

针对Linux环境，日志服务提供可以解压snappy文件的工具，单击snappy_tool下载工具并执行以下代码解压，其中03_1453457006548078722_44148.snappy、03_1453457006548078722_44148请根据实际情况替换。

./snappy_tool 03_1453457006548078722_44148.snappy 03_1453457006548078722_44148
compressed.size: 2217186
snappy::Uncompress return: 1
uncompressed.size: 25223660