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This article mainly introduces "what is the default conversion class of hadoop". In daily operation, I believe that many people have doubts about what the default conversion class of hadoop is. The editor consulted all kinds of information and sorted out a simple and easy-to-use method of operation. I hope it will be helpful to answer the question of "what is the default conversion class of hadoop?" Next, please follow the editor to study!

The default is the following conversion class

Job.setInputFormatClass (TextInputFormat.class)

The List InputFormat.getSplits first splits the input data, and the split split decides the number of tasks of the map in writing.

RecordReader InputFormat.createRecordReader (InputSplit split,...) Pass in the segmented data, process it into key and value, and then send the keyvalue value to map for execution. Each pair of key and value pairs will call map.

FileInputFormat extends InputFormat

List FileInputFormat.getSplits

TextInputFormat extends FileInputFormat

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