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import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;

public class Base {

    // The fromJSON method that parses the JSON and sets the values
    public void fromJSON(String json) {
        try {
            // Manually parse the JSON string into a map of field names and values
            Map<String, String> fields = parseJSON(json);

            // Iterate through the fields and find matching setters using reflection
            for (Map.Entry<String, String> entry : fields.entrySet()) {
                String fieldName = entry.getKey();
                String fieldValue = entry.getValue();

                // Find the setter method corresponding to this field
                String setterMethodName = "set" + capitalize(fieldName);
                Method setterMethod = findSetterMethod(setterMethodName, fieldValue);

                if (setterMethod != null) {
                    // Invoke the setter method with the appropriate value
                    invokeSetter(setterMethod, fieldValue);
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // Manually parse the JSON string into a Map<String, String>
    private Map<String, String> parseJSON(String json) {
        Map<String, String> fields = new HashMap<>();
        
        // Remove surrounding curly braces and trim the string
        json = json.trim().substring(1, json.length() - 1).trim();

        // Split the JSON string into key-value pairs
        String[] keyValuePairs = json.split(",\\s*");

        // Loop through the pairs and extract key-value
        for (String pair : keyValuePairs) {
            String[] keyValue = pair.split(":\\s*");
            String key = keyValue[0].trim().replaceAll("\"", ""); // Remove quotes around key
            String value = keyValue[1].trim().replaceAll("\"", ""); // Remove quotes around value

            // Handle values without quotes as well (like numbers or booleans)
            fields.put(key, value);
        }
        return fields;
    }

    // Capitalizes the first letter of a string (helper method for setter name matching)
    private String capitalize(String fieldName) {
        return fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1);
    }

    // Find a matching setter method using reflection
    private Method findSetterMethod(String setterMethodName, String fieldValue) {
        try {
            // Check for setter methods in the current class
            for (Method method : this.getClass().getMethods()) {
                if (method.getName().equals(setterMethodName)) {
                    if (method.getParameterCount() == 1) {
                        // Match based on the parameter type
                        Class<?> paramType = method.getParameterTypes()[0];
                        if (paramType.equals(String.class)) {
                            return method;
                        } else if (paramType.equals(int.class) && isInteger(fieldValue)) {
                            return method;
                        } else if (paramType.equals(double.class) && isDouble(fieldValue)) {
                            return method;
                        } else if (paramType.equals(boolean.class) && isBoolean(fieldValue)) {
                            return method;
                        }
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    // Invokes the setter method dynamically using reflection
    private void invokeSetter(Method setterMethod, String fieldValue) {
        try {
            Class<?> paramType = setterMethod.getParameterTypes()[0];
            if (paramType.equals(String.class)) {
                setterMethod.invoke(this, fieldValue);
            } else if (paramType.equals(int.class)) {
                setterMethod.invoke(this, Integer.parseInt(fieldValue));
            } else if (paramType.equals(double.class)) {
                setterMethod.invoke(this, Double.parseDouble(fieldValue));
            } else if (paramType.equals(boolean.class)) {
                setterMethod.invoke(this, Boolean.parseBoolean(fieldValue));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // Helper method to check if a string represents an integer
    private boolean isInteger(String value) {
        try {
            Integer.parseInt(value);
            return true;
        } catch (NumberFormatException e) {
            return false;
        }
    }

    // Helper method to check if a string represents a double
    private boolean isDouble(String value) {
        try {
            Double.parseDouble(value);
            return true;
        } catch (NumberFormatException e) {
            return false;
        }
    }

    // Helper method to check if a string represents a boolean
    private boolean isBoolean(String value) {
        return value.equalsIgnoreCase("true") || value.equalsIgnoreCase("false");
    }
}

class Person extends Base {

    private String name;
    private int age;

    // Getter and Setter methods

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "Person{name='" + name + "', age=" + age + "}";
    }
}

public class Main {
    public static void main(String[] args) {
        String json = "{\"Name\": \"John\", \"Age\": 33}";
        
        Person person = new Person();
        person.fromJSON(json);
        System.out.println(person);  // Output: Person{name='John', age=33}

        // Another example with booleans and doubles
        String json2 = "{\"Name\": \"Alice\", \"Age\": 28, \"IsEmployed\": true, \"Salary\": 55000.50}";
        Person person2 = new Person();
        person2.fromJSON(json2);
        System.out.println(person2);  // Output: Person{name='Alice', age=28}
    }
}
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