JsonFileMerger

Simple Java Program Merges Json files in a folder into one big json file. I have used it to create a 10GB+ json file from 1m+ small json files, memory is kept below 100MB whilst running. The program accepts 4 arguments:

• Input Folder (The folder containing all the small Json files)
• Output Folder (The folder where the large json file is to be output)
• Array Name (The array name for the combined objects)
• Encoding (Encoding for the json, accepted values are: UTF8 (default if not set),UTF16_BE, UTF16_LE, UTF32_BE, UTF32_LE)

Example: 3 json files
File John.json

{"name":"John", "age":30}

File Mark.json

{"name":"Mark", "age":30}

File Phil.json

{"name":"Phil", "age":30}

With an Array Name of "People" will output to:

{
  "People": [
    {
      "name": "John",
      "age": 30
    },
    {
      "name": "Mark",
      "age": 30
    },
    {
      "name": "Phil",
      "age": 30
    }
  ]
}