MapReduce

  • Using the MR node, you can directly execute the MR program. For the mr node, the worker will use the hadoop jar method to submit tasks

Drag the PNG task node in the toolbar to the drawing board, as shown in the following figure:

JAVA program

  • The class of the main function: is the full path of the Main Class, the entry point of the MR program
  • Program type: select JAVA language
  • Main jar package: is the MR jar package
  • Command line parameters: set the input parameters of the MR program and support the substitution of custom parameter variables
  • Other parameters: support -D, -files, -libjars, -archives format
  • Resource: If the resource file is referenced in other parameters, you need to select and specify in the resource
  • User-defined parameter: It is a user-defined parameter of the MR part, which will replace the content with ${variable} in the script

Python program

  • Program type: select Python language
  • Main jar package: is the Python jar package for running MR
  • Other parameters: support -D, -mapper, -reducer, -input -output format, here you can set the input of user-defined parameters, such as:
  • -mapper "mapper.py 1" -file mapper.py -reducer reducer.py -file reducer.py –input /journey/words.txt -output /journey/out/mr/${currentTimeMillis}
  • The mapper.py 1 after -mapper is two parameters, the first parameter is mapper.py, and the second parameter is 1
  • Resource: If the resource file is referenced in other parameters, you need to select and specify in the resource
  • User-defined parameter: It is a user-defined parameter of the MR part, which will replace the content with ${variable} in the script