Task.java

import java.time.LocalDateTime;

public class Task {
	private int id;
	private String description;
	private String status; // e.g: todo, in-progress, done
	private LocalDateTime createdAt;
	private LocalDateTime updatedAt;

	public Task(int id, String description, String status, LocalDateTime createdAt, LocalDateTime updatedAt) {
		this.id = id;
		this.description = description;
		this.status = status;
		this.createdAt = createdAt;
		this.updatedAt = updatedAt;
	}

	public Task(String description) {
		this.description = description;
		this.status = "todo";
		this.createdAt = LocalDateTime.now();
		this.updatedAt = LocalDateTime.now();
	}

	public int getID() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getDescription() {
		return description;
	}

	public void setDescription(String description) {
		this.description = description;
	}

	public String getStatus() {
		return status;
	}

	public void setStatus(String status) {
		this.status = status;
	}

	public LocalDateTime getCreatedAt() {
		return createdAt;
	}

	public void setCreatedAt(LocalDateTime createdAt) {
		this.createdAt = createdAt;
	}

	public LocalDateTime getUpdatedAt() {
		return updatedAt;
	}

	public void setUpdatedAt(LocalDateTime updatedAt) {
		this.updatedAt = updatedAt;
	}

	@Override
	public String toString() {
		return "{" + "ID: " + id + "\n" + "Description: " + description + "\n" + "Status: " + status + "\n" + "Created at: " + createdAt + "\n" + "Updated at: " + updatedAt + "}";
	}

	public static String escape(String text) {
		return text.replace("\"", "\\\"");
	}

	// convert to JSON format
	public String toJSON() {
		return String.format("{\"id\":%d,\"description\":\"%s\",\"status\":\"%s\",\"createdAt\":\"%s\",\"updatedAt\":\"%s\"}", id, escape(description), status, createdAt.toString(), updatedAt.toString());
	}

	// convert from JSON format
	public static Task fromJSON(String json) {
		// eliminate {, }
		json = json.trim();
		if (json.startsWith("{")) json = json.substring(1);

		if (json.endsWith("}")) json = json.substring(0, json.length() - 1);

		String[] pairs = json.split(",");

		int id = 0;
		String description = "";
		String status = "";
		LocalDateTime createdAt = null;
		LocalDateTime updatedAt = null;

		for (String pair : pairs) {
			// split \"id\":%d, into 2, like this \"id\" and %d
			String[] keyValue = pair.split(":", 2);
			// eliminate \", \"id\" becomes id
			String key = keyValue[0].replace("\"", "").trim();
			String value = keyValue[1].replace("\"", "").trim();

			if (key.equals("id")) {
				id = Integer.parseInt(value);
			} else if (key.equals("description")) {
				description = value;
			} else if (key.equals("status")) {
				status = value;
			} else if (key.equals("createdAt")) {
				createdAt = LocalDateTime.parse(value);
			} else if (key.equals("updatedAt")) {
				updatedAt = LocalDateTime.parse(value);
			}
		}

		return new Task(id, description, status, createdAt, updatedAt);
	}
}