hadoop 读取文件操作

1. Path hdfsPath = new Path(args[0]);  
2. Configuration conf = new Configuration();  
3. FileSystem fs = FileSystem.get(hdfsPath.toUri(),conf);   
4. CompressionCodecFactory factory = new CompressionCodecFactory(conf);  
5. CompressionCodec codec = factory.getCodec(hdfsPath);  
6.   
7. FSDataInputStream inputStream = fs.open(hdfsPath);  
8. BufferedReader reader = null;  
9.   
10. try {  
11.     if (codec == null) {  
12.         reader = new BufferedReader(new InputStreamReader(inputStream));  
13.     } else {  
14.         CompressionInputStream comInputStream = codec.createInputStream(inputStream);  
15.         reader = new BufferedReader(new InputStreamReader(comInputStream));  
16.     }  
17. } catch (Exception e) {  
18.     e.printStackTrace();  
19. }