五：Edits Viewer离线日志查看器
离线日志查看器可以将二进制日志翻译成可读的文件(如XML)，只有当hadoop集群停止时才能使用。输入文件支持的类型：XML和二进制。输出文件支持类型：XML 二进制 Stats(标准输出？)
使用方法：bash$ bin/hdfs oev -i edits -o edits.xml
| Flag | Description |
| [-i ; --inputFile] input file | Specify the input edits log file to process. Xml (case insensitive) extension means XML format otherwise binary format is assumed. Required. |
| [-o ; --outputFile]output file | Specify the output filename, if the specified output processor generates one. If the specified file already exists, it is silently overwritten. Required. |
| [-p ; --processor]processor | Specify the image processor to apply against the image file. Currently valid options are binary, xml (default) and stats. |
| [-v ; --verbose] | Print the input and output filenames and pipe output of processor to console as well as specified file. On extremely large files, this may increase processing time by an order of magnitude. |
| [-h ; --help] | Display the tool usage and help information and exit. |
