How do I get a list of all JSON paths to values from a JSON String?

Question

My goal is to read a JSON file and understand the location of all the values, so that when I encounter that same JSON, I can easily read all the values. I am looking for a w

Answer 1

Refer to this utility : https://github.com/wnameless/json-flattener Perfect answer to your requirement. Provides Flattened map and Flattened strings for complex json strings. I am not the author of this but have used it successfully for my usecase.

Answer 2

I came up with a solution, sharing in case anyone else is looking for the same thing:

public class JsonParser {

    private List<String> pathList;
    private String json;

    public JsonParser(String json) {
        this.json = json;
        this.pathList = new ArrayList<String>();
        setJsonPaths(json);
    }

    public List<String> getPathList() {
        return this.pathList;
    }

    private void setJsonPaths(String json) {
        this.pathList = new ArrayList<String>();
        JSONObject object = new JSONObject(json);
        String jsonPath = "$";
        if(json != JSONObject.NULL) {
            readObject(object, jsonPath);
        }   
    }

    private void readObject(JSONObject object, String jsonPath) {
        Iterator<String> keysItr = object.keys();
        String parentPath = jsonPath;
        while(keysItr.hasNext()) {
            String key = keysItr.next();
            Object value = object.get(key);
            jsonPath = parentPath + "." + key;

            if(value instanceof JSONArray) {            
                readArray((JSONArray) value, jsonPath);
            }
            else if(value instanceof JSONObject) {
                readObject((JSONObject) value, jsonPath);
            } else { // is a value
                this.pathList.add(jsonPath);    
            }          
        }  
    }

    private void readArray(JSONArray array, String jsonPath) {      
        String parentPath = jsonPath;
        for(int i = 0; i < array.length(); i++) {
            Object value = array.get(i);        
            jsonPath = parentPath + "[" + i + "]";

            if(value instanceof JSONArray) {
                readArray((JSONArray) value, jsonPath);
            } else if(value instanceof JSONObject) {                
                readObject((JSONObject) value, jsonPath);
            } else { // is a value
                this.pathList.add(jsonPath);
            }       
        }
    }

}