Solution-Patch 1

app/build.gradle

@@ -1,13 +1,12 @@
 apply plugin: 'com.android.application'
 
 android {
-    compileSdkVersion 23
-    buildToolsVersion "23.0.2"
+    compileSdkVersion 29
 
     defaultConfig {
         applicationId "com.example.android.soonami"
         minSdkVersion 15
-        targetSdkVersion 23
+        targetSdkVersion 29
         versionCode 1
         versionName "1.0"
     }
@@ -20,7 +19,7 @@ android {
 }
 
 dependencies {
-    compile fileTree(dir: 'libs', include: ['*.jar'])
-    testCompile 'junit:junit:4.12'
-    compile 'com.android.support:appcompat-v7:23.4.0'
+    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    testImplementation 'junit:junit:4.12'
+    implementation 'androidx.appcompat:appcompat:1.1.0'
 }

app/src/main/java/com/example/android/soonami/MainActivity.java

@@ -17,10 +17,12 @@
 
 import android.os.AsyncTask;
 import android.os.Bundle;
-import android.support.v7.app.AppCompatActivity;
+import android.text.TextUtils;
 import android.util.Log;
 import android.widget.TextView;
 
+import androidx.appcompat.app.AppCompatActivity;
+
 import org.json.JSONArray;
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -40,12 +42,16 @@
  */
 public class MainActivity extends AppCompatActivity {
 
-    /** Tag for the log messages */
+    /**
+     * Tag for the log messages
+     */
     public static final String LOG_TAG = MainActivity.class.getSimpleName();
 
-    /** URL to query the USGS dataset for earthquake information */
+    /**
+     * URL to query the USGS dataset for earthquake information
+     */
     private static final String USGS_REQUEST_URL =
-            "https://earthquake.usgs.gov/fdsnws/event/1/query?format=geojson&starttime=2012-01-01&endtime=2012-12-01&minmagnitude=6";
+            "https://earthquake.usgs.gov/fdsnws/event/1/query?format=geojson&starttime=2014-01-01&endtime=2014-12-01&minmagnitude=7";
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -62,15 +68,15 @@ protected void onCreate(Bundle savedInstanceState) {
      */
     private void updateUi(Event earthquake) {
         // Display the earthquake title in the UI
-        TextView titleTextView = (TextView) findViewById(R.id.title);
+        TextView titleTextView = findViewById(R.id.title);
         titleTextView.setText(earthquake.title);
 
         // Display the earthquake date in the UI
-        TextView dateTextView = (TextView) findViewById(R.id.date);
+        TextView dateTextView = findViewById(R.id.date);
         dateTextView.setText(getDateString(earthquake.time));
 
         // Display whether or not there was a tsunami alert in the UI
-        TextView tsunamiTextView = (TextView) findViewById(R.id.tsunami_alert);
+        TextView tsunamiTextView = findViewById(R.id.tsunami_alert);
         tsunamiTextView.setText(getTsunamiAlertString(earthquake.tsunamiAlert));
     }
 
@@ -154,6 +160,11 @@ private URL createUrl(String stringUrl) {
          */
         private String makeHttpRequest(URL url) throws IOException {
             String jsonResponse = "";
+
+            // If the url is null, then return early.
+            if (url == null) {
+                return jsonResponse;
+            }
             HttpURLConnection urlConnection = null;
             InputStream inputStream = null;
             try {
@@ -162,10 +173,19 @@ private String makeHttpRequest(URL url) throws IOException {
                 urlConnection.setReadTimeout(10000 /* milliseconds */);
                 urlConnection.setConnectTimeout(15000 /* milliseconds */);
                 urlConnection.connect();
-                inputStream = urlConnection.getInputStream();
-                jsonResponse = readFromStream(inputStream);
+
+                //If the request was successful(response code 200)
+                // then read the input stream and parse the response.
+                if (urlConnection.getResponseCode() == 200) {
+                    inputStream = urlConnection.getInputStream();
+                    jsonResponse = readFromStream(inputStream);
+                } else {
+                    Log.e(LOG_TAG, "Error response code" + urlConnection.getResponseCode());
+                }
+
             } catch (IOException e) {
-                // TODO: Handle the exception
+                Log.e(LOG_TAG, "Problem retrieving the earthquake JSON results", e);
+
             } finally {
                 if (urlConnection != null) {
                     urlConnection.disconnect();
@@ -201,6 +221,10 @@ private String readFromStream(InputStream inputStream) throws IOException {
          * about the first earthquake from the input earthquakeJSON string.
          */
         private Event extractFeatureFromJson(String earthquakeJSON) {
+            // If the JSON string is empty or null, then return early.
+            if (TextUtils.isEmpty(earthquakeJSON)) {
+                return null;
+            }
             try {
                 JSONObject baseJsonResponse = new JSONObject(earthquakeJSON);
                 JSONArray featureArray = baseJsonResponse.getJSONArray("features");

build.gradle

@@ -3,9 +3,14 @@
 buildscript {
     repositories {
         jcenter()
+        maven {
+            url 'https://maven.google.com/'
+            name 'Google'
+        }
+        google()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:2.1.0'
+        classpath 'com.android.tools.build:gradle:3.5.3'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files
@@ -15,6 +20,10 @@ buildscript {
 allprojects {
     repositories {
         jcenter()
+        maven {
+            url 'https://maven.google.com/'
+            name 'Google'
+        }
     }
 }