java将grib2数据转为json格式

grib2json ========= A command line utility that decodes [GRIB2](http://en.wikipedia.org/wiki/GRIB) files as JSON. This utility uses the netCDF-Java GRIB decoder, part of the [THREDDS](https://github.com/Unidata/thredds) project by University Corporation for Atmospheric Research/Unidata. Installation ------------ ``` git clone <this project> mvn package ``` This creates a .tar.gz in the target directory. Unzip and untar the package in a location of choice. Usage ----- The `grib2json` launch script is located in the `bin` directory and requires the `JAVA_HOME` environment variable to be defined. ``` > grib2json --help Usage: grib2json [options] FILE [--compact -c] : enable compact Json formatting [--data -d] : print GRIB record data [--filter.category --fc value] : select records with this numeric category [--filter.parameter --fp value] : select records with this numeric parameter [--filter.surface --fs value] : select records with this numeric surface type [--filter.value --fv value] : select records with this numeric surface value [--help -h] : display this help [--names -n] : print names of numeric codes [--output -o value] : write output to the specified file (default is stdout) [--verbose -v] : enable logging to stdout ``` For example, the following command outputs to stdout the records for parameter 2 (U-component_of_wind), with surface type 103 (Specified height level above ground), and surface value 10.0 meters from the GRIB2 file _gfs.t18z.pgrbf00.2p5deg.grib2_. Notice the optional inclusion of human-readable _xyzName_ keys and the data array: ``` > grib2json --names --data --fp 2 --fs 103 --fv 10.0 gfs.t18z.pgrbf00.2p5deg.grib2 [ { "header":{ "discipline":0, "disciplineName":"Meteorological products", "gribEdition":2, "gribLength":27759, "center":7, "centerName":"US National Weather Service - NCEP(WMC)", "parameterNumber":2, "parameterNumberName":"U-component_of_wind", "parameterUnit":"m.s-1", "surface1Type":103, "surface1TypeName":"Specified height level above ground", "surface1Value":10.0, ... }, "data":[ -2.12, -2.27, -2.41, ... ] } ] ```