JSON

jq - Cheatsheet

jq - Extract value from JSON

With array index:

cat my.json | jq -r '.[] | .id'

Without array index:

cat my.json | jq -r '.config .id'

jq - Remove quotes from output value

jq -r $input

jq - Filter by keyword in value

cat my.json | jq -c '.[] | select( ._id | contains(611))'

jq - Filter by exact match

cat my.json | jq -c '.[] | select( ._id == 611 )'

jq - Map output to a new array

cat my.json | jq -c 'map( select( ._id == 611 ) )'

jq - Resources

Java

Pretty print JSON representation of an object in Java

  • JSONObject

    // Pretty print an object
import org.json.JSONObject;
 
var jsonObject = new JSONObject();
jsonObject.put("key", "value");
log.info(jsonObject.toString(4)); // 4 is indentation level
 
// Pretty print a JSON string
var jsonString = "{\"key\": \"value\"}";
log.info(jsonString.toString(4));

  • Jackson

     
import com.fasterxml.jackson.databind.ObjectMapper;
 
var objectMapper = new ObjectMapper();
var jsonObject = objectMapper.createObjectNode();
jsonObject.put("key", "value");
log.info(objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(jsonObject));

Pretty print JSON string in Java

  • org.json.JSONObject

    Artifact: org.json:json:20210307

    log.info("Pretty JSON: {}", new org.json.JSONObject("""
        {"timestamp":"2025-02-06T03:13:19.186+00:00","status":404,"error":"Not Found","path":"/ms-message-hub/v1/ccom/customers/30000/00e805e9-596d-4893-8836-8ab2918f70a9"}
        """).toString(4));

    Output:

    // Pretty JSON:
{
  "path": "/ms-message-hub/v1/ccom/customers/30000/00e805e9-596d-4893-8836-8ab2918f70a9",
  "error": "Not Found",
  "timestamp": "2025-02-06T03:13:19.186+00:00",
  "status": 404
}

JSON Lines

  • JSON Lines (opens in a new tab)

    • Features

      • For storing structured data that may be processed one record at a time
      • Works well with unix-style text processing tools and shell pipelines
      • Great format for log files
      • Flexible format for streaming messages
      • Good for compress lengthy JSON data with lots of lines
      • Better replacement for CSV

    • Format

      • UTF-8 Encoding
      • Each Line is a Valid JSON Value
      • Line Terminator is \n

    • Recommended practices

      • JSON Lines files may be saved with the file extension .jsonl.
      • MIME type may be application/jsonl
      • Stream compressors like gzip or bzip2 are recommended for saving space, resulting in .jsonl.gz or .jsonl.bz2 files.
Java - ConcurrencyHashiCorp Vault