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Unable to resolve host "" No address associated with hostname

java
network-requests
android-development
best-practices
Alex KataevbyAlex Kataev·Nov 25, 2024
TLDR
Make sure the URL is valid and the device is connected to the internet. Don't forget to include the internet permission in your AndroidManifest.xml file. 

```xml
<uses-permission android:name="android.permission.INTERNET" />

You might also consider setting a well-known DNS such as 8.8.8.8 and 1.1.1.1. Finally, try to test the URL in a browser or use ping to check the internet connection.

Check manifest and permissions

First, confirm that you're requesting the necessary internet permission in your AndroidManifest.xml. It needs to be placed within the <manifest> tag but before </manifest> tag. Permissions misplacement can lead to your internet request being denied.

// Your app asking for internet access is like a kid asking for a cookie. An innocent request, but the parent (the OS) needs to approve! <uses-permission android:name="android.permission.INTERNET" />

Network connection sanity check

It's essential to confirm whether your device or emulator has a stable internet connection. You can restart your emulator or even your physical device if you're experiencing network-related issues. They're just like humans, they need a reboot every now and then!

URL Validity and Accessibility

Make sure the URL you're requesting is correct and accessible. Try accessing the URL from different browsers or even different devices. If it's not accessible, even the Avengers can't help you get a response!

URL url = new URL("https://example.com"); // Some URLs are like Voldemort - They must not be named (or they're just incorrect).

Check your network configuration

Sometimes, system security settings or firewalls could block network requests. Check your settings and ensure your app is allowed to access the internet.

// Even firewalls have a soft spot. Baking some virtual cookies might help to gain their trust! boolean isFirewallNice = checkFirewallSettings();

Employ third-party libraries

Sometimes, third-party libraries can handle network operations more efficiently. For complex tasks, like working with RSS feeds, consider relying on their expertise.

// Standing on the shoulders of giants, or in this case, third-party libraries. RssReader reader = new RssReader();

Validate domain and DNS

Ensure that the URL domain is registered and trusted by the internet community. Even in the digital world, trust issues persist.

// Trust but verify - a principle followed both by secret agents and programmers alike. isDomainTrusted(url);