Николай Бараненко

нашел такое решение, вопрос с условностью проверки наличия атрибута read

for row in cursor.fetchall():
    count_rows+=1
    result_inside={}
    row_content=[]
    for col, val in zip(col_names, row):
        # проверяем наличие атрибута у объекта, если CLOB то приеняем read
        if hasattr(val, 'read'):
            result_inside[col] = val.read()
        else:
            result_inside[col] = val
        row_content.append(result_inside[col])
    json_file.write(json.dumps(result_inside, default = myconverter))

у решения выше есть проблема

Internally, Oracle uses LOB locators which are allocated based on the
cursor array size. Thus, it is important that the data in the LOB
object be manipulated before another internal fetch takes place. The
safest way to do this is to use the cursor as an iterator. In
particular, do not use the fetchall() method.

поэтому

for row in cursor:
    count_rows+=1
    result_inside={}
    row_content=[]
    for col, val in zip(col_names, row):
        # проверяем наличие атрибута у объекта, если CLOB то приеняем read
        if hasattr(val, 'read'):
            result_inside[col] = val.read()
        else:
            result_inside[col] = val
        row_content.append(result_inside[col])
    json_file.write(json.dumps(result_inside, default = myconverter))

Накатил модуль simplejson
в итоге получится как-то так

#!/usr/bin/python
import simplejson as json

part_nums = ['ECA-1EHG102','CL05B103KB5NNNC','CC0402KRX5R8BB104']

def json_list(list):
    lst = []
    for pn in list:
        d = {}
        d['mpn']=pn
        lst.append(d)
    return json.dumps(lst)

print(json_list(part_nums))

класс обертка

public class Employee3 {

private String Employee;
private String Input_Weight1;
private String Input_Weight2;
private String Input_Weight3;

    public String getEmployee() {
        return Employee;
    }

    public void setEmployee(String employee) {
        Employee = employee;
    }

    public String getInput_Weight1() {
        return Input_Weight1;
    }

    public void setInput_Weight1(String input_Weight1) {
        Input_Weight1 = input_Weight1;
    }

    public String getInput_Weight2() {
        return Input_Weight2;
    }

    public void setInput_Weight2(String input_Weight2) {
        Input_Weight2 = input_Weight2;
    }

    public String getInput_Weight3() {
        return Input_Weight3;
    }

    public void setInput_Weight3(String input_Weight3) {
        Input_Weight3 = input_Weight3;
    }
}

сериализация

List<String> Employee = new ArrayList<>();
        List<String> Input_Weight1 = new ArrayList<>();
        List<String> Input_Weight2 = new ArrayList<>();
        List<String> Input_Weight3 = new ArrayList<>();

        Employee.add("сотрудник1");
        Employee.add("сотрудник2");
        Employee.add("сотрудник3");
        Input_Weight1.add("0.2");
        Input_Weight1.add("0");
        Input_Weight1.add("0");
        Input_Weight2.add("0.4");
        Input_Weight2.add("0");
        Input_Weight2.add("0");
        Input_Weight3.add("0.3");
        Input_Weight3.add("0");
        Input_Weight3.add("0");

        Employee3 employee3=null;
        JSONArray jsonobj = new JSONArray();
     //   List<Employee3> map_list=new ArrayList<>();
        for (int i=0; i<Employee.size(); i++){
            employee3=new Employee3();
            employee3.setEmployee(Employee.get(i));
            employee3.setInput_Weight1(Input_Weight1.get(i));
            employee3.setInput_Weight2(Input_Weight2.get(i));
            employee3.setInput_Weight3(Input_Weight3.get(i));
          //  map_list.add(employee3);
           // System.out.println(Employee.get(i));
            jsonobj.put(employee3);
        }

        Gson gson1 = new Gson();
        System.out.println(gson1.toJson(jsonobj));

итого:

List<String> Employee = new ArrayList<>();
        List<String> Input_Weight1 = new ArrayList<>();
        List<String> Input_Weight2 = new ArrayList<>();
        List<String> Input_Weight3 = new ArrayList<>();

        Employee.add("сотрудник1");
        Employee.add("сотрудник2");
        Employee.add("сотрудник3");
        Input_Weight1.add("0.2");
        Input_Weight1.add("0");
        Input_Weight1.add("0");
        Input_Weight2.add("0.4");
        Input_Weight2.add("0");
        Input_Weight2.add("0");
        Input_Weight3.add("0.3");
        Input_Weight3.add("0");
        Input_Weight3.add("0");

        Employee3 employee3=null;
        JSONArray jsonobj = new JSONArray();
     //   List<Employee3> map_list=new ArrayList<>();
        for (int i=0; i<Employee.size(); i++){
            employee3=new Employee3();
            employee3.setEmployee(Employee.get(i));
            employee3.setInput_Weight1(Input_Weight1.get(i));
            employee3.setInput_Weight2(Input_Weight2.get(i));
            employee3.setInput_Weight3(Input_Weight3.get(i));
          //  map_list.add(employee3);
           // System.out.println(Employee.get(i));
            jsonobj.put(employee3);
        }

        Gson gson1 = new Gson();
        System.out.println(gson1.toJson(jsonobj));

результат:

[{"Employee":"сотрудник1","Input_Weight1":"0.2","Input_Weight2":"0.4","Input_Weight3":"0.3"},{"Employee":"сотрудник2","Input_Weight1":"0","Input_Weight2":"0","Input_Weight3":"0"},{"Employee":"сотрудник3","Input_Weight1":"0","Input_Weight2":"0","Input_Weight3":"0"}]

работающий вариант

JSONParser parser = new JSONParser();
JSONObject obj;
try {

    obj = (JSONObject) parser.parse(new FileReader("E:\\json.txt"));

    out.println("<br>"+obj);

    JSONObject jsonObject = (JSONObject) obj;

    JSONArray from_excel = (JSONArray)jsonObject.get("from_excel");
    // вариант построчного вывода 1
    for(Object o: from_excel){
        out.println("<br>"+o);
    }
    // вариант построчного вывода 2
    Iterator iterator = from_excel.iterator();
    while (iterator.hasNext()) {
        out.println("<br>"+iterator.next());
    }
    // вариант поименного вывода 3
    for (int i = 0; i < from_excel.size(); i++) {

        JSONObject jsonObjectRow = (JSONObject) from_excel.get(i);
        String num = (String) jsonObjectRow.get("num");
        String solution = (String) jsonObjectRow.get("solution");
        out.println("<br>num="+num+"; solution="+solution);
    }
} catch (Exception e) {
    out.println("Ошибка: "+e);
}