---
title: "Configure the Advanced I/O function"
url: https://docs.catalyst.zoho.com/en/tutorials/newsapp/java/configure-advancedio/
description: "Build a web news application that automatically fetches news from a third-party service periodically using the Catalyst Job Scheduling Cron component, and a Job Function and Advanced I/O function coded in Java."
last_updated: 2025-11-19T15:07:41Z
service: All Services
type: tutorial
related_links:
  - name: "Advanced I/O Function"
    url: /en/serverless/help/functions/advanced-io
  - name: "Data Store"
    url: /en/cloud-scale/help/data-store/introduction
  - name: "ZCQL"
    url: /en/cloud-scale/help/zcql/introduction
---

# Configure the Advanced I/O Function

The Advanced I/O function directory (`functions/NewsApp_AIO`) contains the following files: 

* The `DataStoreFetch.java` main function file
* The `catalyst-config.json` configuration file
* Java library files in the `lib` folder
* `.classpath` and `.project` dependency files

You will be adding code in the `DatastoreFetch.java` file.

The Advanced I/O function fetches the news item from its source table in the Data Store and forwards it to the client component as a JSON response.

Copy the code and paste it in the  `DatastoreFetch.java ` in the  `functions/NewsApp_AIO ` directory.

**DatastoreFetch.java**

```java
import java.util.logging.Logger;
import java.util.ArrayList;
import java.util.logging.Level;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.catalyst.advanced.CatalystAdvancedIOHandler;
import com.zc.component.object.ZCRowObject;
import com.zc.component.zcql.ZCQL;
import org.json.JSONArray;
import org.json.JSONObject;
public class DatastoreFetch implements CatalystAdvancedIOHandler {
    private static final Logger LOGGER = Logger.getLogger(DatastoreFetch.class.getName());
    @Override
    public void runner(HttpServletRequest request, HttpServletResponse response) throws Exception {
        try {
            // Fetch the endpoint and HTTP method
            String url = request.getRequestURI();
            String method = request.getMethod();
            if (url.equals("/fetchData") && method.equals("GET")) {
                String tableName = request.getParameter("tablename");
                // Query the Data Store using ZCQL
                String query = "select title, url from " + tableName;
                ArrayList<ZCRowObject> rowList = ZCQL.getInstance().executeQuery(query);
                JSONObject data = new JSONObject();
                JSONArray content = new JSONArray();
                // Construct JSON response
                for (int i = 0; i < rowList.size(); i++) {
                    JSONObject rowData = new JSONObject();
                    JSONObject tableData = new JSONObject();
                    ZCRowObject row = rowList.get(i);
                    String title = (String) row.get("title");
                    String urlVal = (String) row.get("url");
                    rowData.put("title", title);
                    rowData.put("url", urlVal);
                    tableData.put(tableName, rowData);
                    content.put(tableData);
                }
                data.put("content", content);
                // Send response back to client
                response.setContentType("application/json");
                response.getWriter().write(data.toString());
                response.setStatus(200);
            } else {
                // Invalid request
                LOGGER.log(Level.SEVERE, "Error. Invalid Request");
                response.setStatus(404);
            }
        } catch (Exception e) {
            LOGGER.log(Level.SEVERE, "Exception in DatastoreFetch", e);
            response.setStatus(500);
        }
    }
}

```

The Advanced I/O function is now configured. We will discuss the application's architecture after we configure the client.