Fix version warnings for gradle builds (#87)

* Add a `presubmit` target to run formatter and lint.
* Add dev process to README
* Gradle config improvements
* Changes made by linter

5 files changed, 55 insertions, 37 deletions

diff --git a/src/main/java/com/google/android/mobly/snippet/bundled/AccountSnippet.java b/src/main/java/com/google/android/mobly/snippet/bundled/AccountSnippet.java
index 627d1b4..f8499b4 100644
--- a/src/main/java/com/google/android/mobly/snippet/bundled/AccountSnippet.java
+++ b/src/main/java/com/google/android/mobly/snippet/bundled/AccountSnippet.java
@@ -34,6 +34,7 @@ import java.util.HashMap;
 import java.util.HashSet;
 import java.util.LinkedList;
 import java.util.List;
+import java.util.Locale;
 import java.util.Map;
 import java.util.Set;
 import java.util.TreeSet;
@@ -112,6 +113,7 @@ public class AccountSnippet implements Snippet {
         if (result.containsKey(AccountManager.KEY_ERROR_CODE)) {
             throw new AccountSnippetException(
                     String.format(
+                            Locale.US,
                             "Failed to add account due to code %d: %s",
                             result.getInt(AccountManager.KEY_ERROR_CODE),
                             result.getString(AccountManager.KEY_ERROR_MESSAGE)));
diff --git a/src/main/java/com/google/android/mobly/snippet/bundled/FileSnippet.java b/src/main/java/com/google/android/mobly/snippet/bundled/FileSnippet.java
index 571d57f..f6b6918 100644
--- a/src/main/java/com/google/android/mobly/snippet/bundled/FileSnippet.java
+++ b/src/main/java/com/google/android/mobly/snippet/bundled/FileSnippet.java
@@ -16,10 +16,6 @@
 
 package com.google.android.mobly.snippet.bundled;
 
-import java.io.IOException;
-import java.security.MessageDigest;
-import java.security.DigestInputStream;
-import java.security.NoSuchAlgorithmException;
 import android.content.Context;
 import android.net.Uri;
 import android.os.ParcelFileDescriptor;
@@ -27,6 +23,10 @@ import android.support.test.InstrumentationRegistry;
 import com.google.android.mobly.snippet.Snippet;
 import com.google.android.mobly.snippet.bundled.utils.Utils;
 import com.google.android.mobly.snippet.rpc.Rpc;
+import java.io.IOException;
+import java.security.DigestInputStream;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
 
 /** Snippet class for File and abstract storage URI operation RPCs. */
 public class FileSnippet implements Snippet {
@@ -47,13 +47,14 @@ public class FileSnippet implements Snippet {
     }
 
     @Rpc(description = "Compute MD5 hash on a content URI. Return the MD5 has has a hex string.")
-    public String fileMd5Hash(String uri) throws IOException, NoSuchAlgorithmException  {
+    public String fileMd5Hash(String uri) throws IOException, NoSuchAlgorithmException {
         Uri uri_ = Uri.parse(uri);
         ParcelFileDescriptor pfd = mContext.getContentResolver().openFileDescriptor(uri_, "r");
         MessageDigest md = MessageDigest.getInstance("MD5");
         int length = (int) pfd.getStatSize();
         byte[] buf = new byte[length];
-        ParcelFileDescriptor.AutoCloseInputStream stream = new ParcelFileDescriptor.AutoCloseInputStream(pfd);
+        ParcelFileDescriptor.AutoCloseInputStream stream =
+                new ParcelFileDescriptor.AutoCloseInputStream(pfd);
         DigestInputStream dis = new DigestInputStream(stream, md);
         try {
             dis.read(buf, 0, length);
diff --git a/src/main/java/com/google/android/mobly/snippet/bundled/NetworkingSnippet.java b/src/main/java/com/google/android/mobly/snippet/bundled/NetworkingSnippet.java
index f175fdd..e89fc12 100644
--- a/src/main/java/com/google/android/mobly/snippet/bundled/NetworkingSnippet.java
+++ b/src/main/java/com/google/android/mobly/snippet/bundled/NetworkingSnippet.java
@@ -16,24 +16,24 @@
 
 package com.google.android.mobly.snippet.bundled;
 
-import java.util.List;
-import java.net.InetAddress;
-import java.net.Socket;
-import java.io.IOException;
-import java.net.UnknownHostException;
-import android.content.Intent;
+import android.app.DownloadManager;
+import android.content.BroadcastReceiver;
 import android.content.Context;
+import android.content.Intent;
 import android.content.IntentFilter;
-import android.content.BroadcastReceiver;
 import android.net.Uri;
 import android.os.Environment;
-import android.os.ParcelFileDescriptor;
-import android.app.DownloadManager;
 import android.support.test.InstrumentationRegistry;
 import com.google.android.mobly.snippet.Snippet;
 import com.google.android.mobly.snippet.bundled.utils.Utils;
 import com.google.android.mobly.snippet.rpc.Rpc;
 import com.google.android.mobly.snippet.util.Log;
+import java.io.IOException;
+import java.net.InetAddress;
+import java.net.Socket;
+import java.net.UnknownHostException;
+import java.util.List;
+import java.util.Locale;
 
 /** Snippet class for networking RPCs. */
 public class NetworkingSnippet implements Snippet {
@@ -77,18 +77,23 @@ public class NetworkingSnippet implements Snippet {
         return true;
     }
 
-    @Rpc(description = "Download a file using HTTP. Return content Uri (file remains on device). "
-                       + "The Uri should be treated as an opaque handle for further operations.")
-    public String networkHttpDownload(String url) throws IllegalArgumentException, NetworkingSnippetException {
+    @Rpc(
+        description =
+                "Download a file using HTTP. Return content Uri (file remains on device). "
+                        + "The Uri should be treated as an opaque handle for further operations."
+    )
+    public String networkHttpDownload(String url)
+            throws IllegalArgumentException, NetworkingSnippetException {
 
         Uri uri = Uri.parse(url);
         List<String> pathsegments = uri.getPathSegments();
         if (pathsegments.size() < 1) {
-            throw new IllegalArgumentException(String.format("The Uri %s does not have a path.", uri.toString()));
+            throw new IllegalArgumentException(
+                    String.format(Locale.US, "The Uri %s does not have a path.", uri.toString()));
         }
         DownloadManager.Request request = new DownloadManager.Request(uri);
-        request.setDestinationInExternalPublicDir(Environment.DIRECTORY_DOWNLOADS,
-                                                  pathsegments.get(pathsegments.size() - 1));
+        request.setDestinationInExternalPublicDir(
+                Environment.DIRECTORY_DOWNLOADS, pathsegments.get(pathsegments.size() - 1));
         mIsDownloadComplete = false;
         mReqid = 0;
         IntentFilter filter = new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE);
@@ -96,9 +101,16 @@ public class NetworkingSnippet implements Snippet {
         mContext.registerReceiver(receiver, filter);
         try {
             mReqid = mDownloadManager.enqueue(request);
-            Log.d(String.format("networkHttpDownload download of %s with id %d", url, mReqid));
+            Log.d(
+                    String.format(
+                            Locale.US,
+                            "networkHttpDownload download of %s with id %d",
+                            url,
+                            mReqid));
             if (!Utils.waitUntil(() -> mIsDownloadComplete, 30)) {
-                Log.d(String.format("networkHttpDownload timed out waiting for completion"));
+                Log.d(
+                        String.format(
+                                Locale.US, "networkHttpDownload timed out waiting for completion"));
                 throw new NetworkingSnippetException("networkHttpDownload timed out.");
             }
         } finally {
@@ -106,11 +118,15 @@ public class NetworkingSnippet implements Snippet {
         }
         Uri resp = mDownloadManager.getUriForDownloadedFile(mReqid);
         if (resp != null) {
-            Log.d(String.format("networkHttpDownload completed to %s", resp.toString()));
+            Log.d(String.format(Locale.US, "networkHttpDownload completed to %s", resp.toString()));
             mReqid = 0;
             return resp.toString();
         } else {
-            Log.d(String.format("networkHttpDownload Failed to download %s", uri.toString()));
+            Log.d(
+                    String.format(
+                            Locale.US,
+                            "networkHttpDownload Failed to download %s",
+                            uri.toString()));
             throw new NetworkingSnippetException("networkHttpDownload didn't get downloaded file.");
         }
     }
@@ -121,8 +137,7 @@ public class NetworkingSnippet implements Snippet {
         public void onReceive(Context context, Intent intent) {
             String action = intent.getAction();
             long gotid = (long) intent.getExtras().get("extra_download_id");
-            if (DownloadManager.ACTION_DOWNLOAD_COMPLETE.equals(action)
-                            && gotid == mReqid) {
+            if (DownloadManager.ACTION_DOWNLOAD_COMPLETE.equals(action) && gotid == mReqid) {
                 mIsDownloadComplete = true;
             }
         }
diff --git a/src/main/java/com/google/android/mobly/snippet/bundled/WifiManagerSnippet.java b/src/main/java/com/google/android/mobly/snippet/bundled/WifiManagerSnippet.java
index 6614904..83a42f6 100644
--- a/src/main/java/com/google/android/mobly/snippet/bundled/WifiManagerSnippet.java
+++ b/src/main/java/com/google/android/mobly/snippet/bundled/WifiManagerSnippet.java
@@ -57,7 +57,9 @@ public class WifiManagerSnippet implements Snippet {
 
     public WifiManagerSnippet() {
         mContext = InstrumentationRegistry.getContext();
-        mWifiManager = (WifiManager) mContext.getSystemService(Context.WIFI_SERVICE);
+        mWifiManager =
+                (WifiManager)
+                        mContext.getApplicationContext().getSystemService(Context.WIFI_SERVICE);
     }
 
     @Rpc(
@@ -196,8 +198,8 @@ public class WifiManagerSnippet implements Snippet {
         String SSID = wifiConfig.SSID;
         // Return directly if network is already connected.
         WifiInfo connectionInfo = mWifiManager.getConnectionInfo();
-        if (connectionInfo.getNetworkId() != -1 && connectionInfo.getSSID().equals(wifiConfig.SSID))
-        {
+        if (connectionInfo.getNetworkId() != -1
+                && connectionInfo.getSSID().equals(wifiConfig.SSID)) {
             Log.d("Network " + connectionInfo.getSSID() + " is already connected.");
             return;
         }
diff --git a/src/main/java/com/google/android/mobly/snippet/bundled/utils/Utils.java b/src/main/java/com/google/android/mobly/snippet/bundled/utils/Utils.java
index e4c0dbd..376bcb5 100644
--- a/src/main/java/com/google/android/mobly/snippet/bundled/utils/Utils.java
+++ b/src/main/java/com/google/android/mobly/snippet/bundled/utils/Utils.java
@@ -30,7 +30,7 @@ import java.util.concurrent.TimeoutException;
 
 public final class Utils {
 
-    private final static char[] hexArray = "0123456789abcdef".toCharArray();
+    private static final char[] hexArray = "0123456789abcdef".toCharArray();
 
     private Utils() {}
 
@@ -194,22 +194,20 @@ public final class Utils {
     }
 
     /**
-     * Convert a byte array (binary data) to a hexadecimal string (ASCII)
-     * representation.
-
-     * [\x01\x02] -&gt; "0102"
+     * Convert a byte array (binary data) to a hexadecimal string (ASCII) representation.
+     *
+     * <p>[\x01\x02] -&gt; "0102"
      *
      * @param bytes The array of byte to convert.
      * @return a String with the ASCII hex representation.
      */
     public static String bytesToHexString(byte[] bytes) {
         char[] hexChars = new char[bytes.length * 2];
-        for ( int j = 0; j < bytes.length; j++ ) {
+        for (int j = 0; j < bytes.length; j++) {
             int v = bytes[j] & 0xFF;
             hexChars[j * 2] = hexArray[v >>> 4];
             hexChars[j * 2 + 1] = hexArray[v & 0x0F];
         }
         return new String(hexChars);
     }
-
 }