added new update checker, need to implement into ui

app/build.gradle

@@ -11,8 +11,8 @@ android {
         applicationId "me.brysonsteck.wiimmfiwatcher"
         minSdkVersion 19
         targetSdkVersion 30
-        versionCode 5
-        versionName "1.1.3"
+        versionCode 6
+        versionName "1.1.4"
 
         testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
     }
@@ -33,6 +33,7 @@ android {
 }
 
 dependencies {
+    implementation 'com.google.code.gson:gson:2.8.6'
     def lifecycle_version = "2.3.1"
 
     // ViewModel

app/src/main/java/me/brysonsteck/wiimmfiwatcher/MainActivity.java

@@ -16,7 +16,6 @@ import me.brysonsteck.wiimmfiwatcher.fragments.WatchCodeFragment;
 public class MainActivity extends AppCompatActivity {
     AppDatabase database;
 
-    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -49,6 +48,26 @@ public class MainActivity extends AppCompatActivity {
         });
 
     }
+
+    @Override
+    protected void onStart() {
+        super.onStart();
+        new Thread(() -> {
+            Updater updater = new Updater();
+            updater.compareRelease(BuildConfig.VERSION_NAME);
+            if (updater.isOutdated()) {
+                System.out.println("---------------------------------------------------------------");
+                System.out.println("\tA newer version of Wiimmfi Watcher is available! (" + updater.getNewestRelease() + ")");
+                System.out.println("\tView the release notes and the source code here: " + updater.getGithubRelease());
+                System.out.println("\t---------------------------------------------------------------");
+            } else {
+                System.out.println("---------------------------------------------------------------");
+                System.out.println("\t\t" + updater.getNewestRelease() + " is the latest release of Wiimmfi Watcher.");
+                System.out.println("\t\t---------------------------------------------------------------");
+            }
+        }).start();
+    }
+
     @Override
     protected void onStop() {
         super.onStop();

app/src/main/java/me/brysonsteck/wiimmfiwatcher/Updater.java

@@ -0,0 +1,69 @@
+package me.brysonsteck.wiimmfiwatcher;
+
+import com.google.gson.JsonElement;
+import com.google.gson.JsonObject;
+import com.google.gson.JsonParser;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.net.URL;
+import java.net.URLConnection;
+
+public class Updater {
+
+    public boolean outdated = false;
+    public String newestRelease;
+    public String githubRelease;
+    public String playStore = "https://play.google.com/store/apps/details?id=me.brysonsteck.wiimmfiwatcher";
+
+    public Updater() {
+        try {
+            String json = urlReader();
+            JsonElement root = new JsonParser().parse(json);
+            JsonObject rootObj = root.getAsJsonObject();
+            newestRelease = rootObj.get("current-release").getAsString();
+            githubRelease = rootObj.get("github-release").getAsString();
+        } catch (IOException e) {
+            System.out.println("An error has occurred while attempting to check for updates.");
+            e.printStackTrace();
+        }
+    }
+
+    public String urlReader() throws IOException {
+        URL website = new URL("https://brysonsteck.net/watcher.json");
+        URLConnection connection = website.openConnection();
+        BufferedReader in = new BufferedReader(
+                new InputStreamReader(
+                        connection.getInputStream()));
+
+        StringBuilder response = new StringBuilder();
+        String inputLine;
+
+        while ((inputLine = in.readLine()) != null)
+            response.append(inputLine);
+
+        in.close();
+
+        return response.toString();
+
+    }
+
+    public void compareRelease(String deviceRelease) {
+        if (!deviceRelease.equals(newestRelease)) {
+            outdated = true;
+        }
+    }
+
+    public boolean isOutdated() {
+        return outdated;
+    }
+
+    public String getNewestRelease() {
+        return newestRelease;
+    }
+
+    public String getGithubRelease() {
+        return githubRelease;
+    }
+}