use lambda

app/build.gradle

@@ -78,7 +78,7 @@ android {
     buildTypes {
         //todo re-enable proguard and test coverage
         release {
-//            minifyEnabled true
+            minifyEnabled true
 //            shrinkResources true
             //proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
             if (project.hasProperty("RELEASE_STORE_FILE")) {

app/src/androidTest/java/org/gnucash/android/test/ui/AccountsActivityTest.java

@@ -497,12 +497,7 @@ public void shouldShowWizardOnFirstRun() throws Throwable {
         editor.remove(mAccountsActivity.getString(R.string.key_first_run)).commit();
 
 
-        mActivityRule.runOnUiThread(new Runnable() {
-            @Override
-            public void run() {
-                mAccountsActivity.recreate();
-            }
-        });
+        mActivityRule.runOnUiThread(() -> mAccountsActivity.recreate());
 
         //check that wizard is shown
         onView(withText(mAccountsActivity.getString(R.string.title_setup_gnucash)))
@@ -523,12 +518,9 @@ public void tearDown() throws Exception {
      */
     private void refreshAccountsList() {
         try {
-            mActivityRule.runOnUiThread(new Runnable() {
-                @Override
-                public void run() {
-                    Fragment fragment = mAccountsActivity.getCurrentAccountListFragment();
-                    ((AccountsListFragment) fragment).refresh();
-                }
+            mActivityRule.runOnUiThread(() -> {
+                Fragment fragment = mAccountsActivity.getCurrentAccountListFragment();
+                ((AccountsListFragment) fragment).refresh();
             });
         } catch (Throwable throwable) {
             System.err.println("Failed to refresh fragment");

app/src/androidTest/java/org/gnucash/android/test/ui/PieChartReportTest.java

@@ -225,16 +225,13 @@ public void testSpinner() throws Exception {
     public static ViewAction clickXY(final Position horizontal, final Position vertical){
         return new GeneralClickAction(
                 Tap.SINGLE,
-                new CoordinatesProvider() {
-                    @Override
-                    public float[] calculateCoordinates(View view) {
-                        int[] xy = new int[2];
-                        view.getLocationOnScreen(xy);
-
-                        float x = horizontal.getPosition(xy[0], view.getWidth());
-                        float y = vertical.getPosition(xy[1], view.getHeight());
-                        return new float[]{x, y};
-                    }
+                view -> {
+                    int[] xy = new int[2];
+                    view.getLocationOnScreen(xy);
+
+                    float x = horizontal.getPosition(xy[0], view.getWidth());
+                    float y = vertical.getPosition(xy[1], view.getHeight());
+                    return new float[]{x, y};
                 },
                 Press.FINGER);
     }
@@ -267,12 +264,7 @@ public float getPosition(int viewPos, int viewLength) {
      */
     private void refreshReport(){
         try {
-            mActivityRule.runOnUiThread(new Runnable() {
-                @Override
-                public void run() {
-                    mReportsActivity.refresh();
-                }
-            });
+            mActivityRule.runOnUiThread(() -> mReportsActivity.refresh());
         } catch (Throwable t){
             System.err.println("Faile to refresh reports");
         }

app/src/androidTest/java/org/gnucash/android/test/ui/TransactionsActivityTest.java

@@ -884,12 +884,7 @@ private void clickOnView(int viewId) {
      */
     private void refreshTransactionsList() {
         try {
-            mActivityRule.runOnUiThread(new Runnable() {
-                @Override
-                public void run() {
-                    mTransactionsActivity.refresh();
-                }
-            });
+            mActivityRule.runOnUiThread(() -> mTransactionsActivity.refresh());
         } catch (Throwable throwable) {
             System.err.println("Failed to refresh fragment");
         }

app/src/main/java/org/gnucash/android/db/MigrationHelper.java

@@ -188,43 +188,40 @@ static void moveFile(File src, File dst) throws IOException {
      * <p>The new folder structure also futher enables parallel installation of multiple flavours of
      * the program (like development and production) on the same device.</p>
      */
-    static final Runnable moveExportedFilesToNewDefaultLocation = new Runnable() {
-        @Override
-        public void run() {
-            File oldExportFolder = new File(Environment.getExternalStorageDirectory() + "/gnucash");
-            if (oldExportFolder.exists()){
-                for (File src : oldExportFolder.listFiles()) {
-                    if (src.isDirectory())
-                        continue;
-                    File dst = new File(Exporter.LEGACY_BASE_FOLDER_PATH + "/exports/" + src.getName());
-                    try {
-                        MigrationHelper.moveFile(src, dst);
-                    } catch (IOException e) {
-                        Log.e(LOG_TAG, "Error migrating " + src.getName());
-                        Crashlytics.logException(e);
-                    }
+    static final Runnable moveExportedFilesToNewDefaultLocation = () -> {
+        File oldExportFolder = new File(Environment.getExternalStorageDirectory() + "/gnucash");
+        if (oldExportFolder.exists()){
+            for (File src : oldExportFolder.listFiles()) {
+                if (src.isDirectory())
+                    continue;
+                File dst = new File(Exporter.LEGACY_BASE_FOLDER_PATH + "/exports/" + src.getName());
+                try {
+                    MigrationHelper.moveFile(src, dst);
+                } catch (IOException e) {
+                    Log.e(LOG_TAG, "Error migrating " + src.getName());
+                    Crashlytics.logException(e);
                 }
-            } else {
-                //if the base folder does not exist, no point going one level deeper
-                return;
             }
+        } else {
+            //if the base folder does not exist, no point going one level deeper
+            return;
+        }
 
-            File oldBackupFolder = new File(oldExportFolder, "backup");
-            if (oldBackupFolder.exists()){
-                for (File src : new File(oldExportFolder, "backup").listFiles()) {
-                    File dst = new File(Exporter.LEGACY_BASE_FOLDER_PATH + "/backups/" + src.getName());
-                    try {
-                        MigrationHelper.moveFile(src, dst);
-                    } catch (IOException e) {
-                        Log.e(LOG_TAG, "Error migrating backup: " + src.getName());
-                        Crashlytics.logException(e);
-                    }
+        File oldBackupFolder = new File(oldExportFolder, "backup");
+        if (oldBackupFolder.exists()){
+            for (File src : new File(oldExportFolder, "backup").listFiles()) {
+                File dst = new File(Exporter.LEGACY_BASE_FOLDER_PATH + "/backups/" + src.getName());
+                try {
+                    MigrationHelper.moveFile(src, dst);
+                } catch (IOException e) {
+                    Log.e(LOG_TAG, "Error migrating backup: " + src.getName());
+                    Crashlytics.logException(e);
                 }
             }
-
-            if (oldBackupFolder.delete())
-                oldExportFolder.delete();
         }
+
+        if (oldBackupFolder.delete())
+            oldExportFolder.delete();
     };
 
     /**
@@ -1548,28 +1545,25 @@ public static int upgradeDbToVersion14(SQLiteDatabase db){
         File backupFolder = new File(Exporter.BASE_FOLDER_PATH);
         backupFolder.mkdir();
 
-        new Thread(new Runnable() {
-            @Override
-            public void run() {
-                File srcDir = new File(Exporter.LEGACY_BASE_FOLDER_PATH);
-                File dstDir = new File(Exporter.BASE_FOLDER_PATH);
-                try {
-                    moveDirectory(srcDir, dstDir);
-                    File readmeFile = new File(Exporter.LEGACY_BASE_FOLDER_PATH, "README.txt");
-                    FileWriter writer = null;
-                    writer = new FileWriter(readmeFile);
-                    writer.write("Backup files have been moved to " + dstDir.getPath() +
-                            "\nYou can now delete this folder");
-                    writer.flush();
-                } catch (IOException | IllegalArgumentException ex) {
-                    ex.printStackTrace();
-                    String msg = String.format("Error moving files from %s to %s", srcDir.getPath(), dstDir.getPath());
-                    Log.e(LOG_TAG, msg);
-                    Crashlytics.log(msg);
-                    Crashlytics.logException(ex);
-                }
-
+        new Thread(() -> {
+            File srcDir = new File(Exporter.LEGACY_BASE_FOLDER_PATH);
+            File dstDir = new File(Exporter.BASE_FOLDER_PATH);
+            try {
+                moveDirectory(srcDir, dstDir);
+                File readmeFile = new File(Exporter.LEGACY_BASE_FOLDER_PATH, "README.txt");
+                FileWriter writer = null;
+                writer = new FileWriter(readmeFile);
+                writer.write("Backup files have been moved to " + dstDir.getPath() +
+                        "\nYou can now delete this folder");
+                writer.flush();
+            } catch (IOException | IllegalArgumentException ex) {
+                ex.printStackTrace();
+                String msg = String.format("Error moving files from %s to %s", srcDir.getPath(), dstDir.getPath());
+                Log.e(LOG_TAG, msg);
+                Crashlytics.log(msg);
+                Crashlytics.logException(ex);
             }
+
         }).start();
 
         return 14;

app/src/main/java/org/gnucash/android/db/adapter/BooksDbAdapter.java

@@ -166,8 +166,8 @@ public boolean isActive(String bookUID){
             if (cursor.getCount() == 0) {
                 NoActiveBookFoundException e = new NoActiveBookFoundException(
                         "There is no active book in the app."
-                        + "This should NEVER happen, fix your bugs!\n"
-                        + getNoActiveBookFoundExceptionInfo());
+                                + "This should NEVER happen, fix your bugs!\n"
+                                + getNoActiveBookFoundExceptionInfo());
                 e.printStackTrace();
                 throw e;
             }
@@ -187,7 +187,7 @@ private String getNoActiveBookFoundExceptionInfo() {
         return info.toString();
     }
 
-    public class NoActiveBookFoundException extends RuntimeException {
+    public static class NoActiveBookFoundException extends RuntimeException {
         public NoActiveBookFoundException(String message) {
             super(message);
         }

app/src/main/java/org/gnucash/android/db/adapter/PricesDbAdapter.java

@@ -118,7 +118,7 @@ public Pair<Long, Long> getPrice(@NonNull String commodityUID, @NonNull String c
                     valueNum = valueDenom;
                     valueDenom = t;
                 }
-                return new Pair<Long, Long>(valueNum, valueDenom);
+                return new Pair<>(valueNum, valueDenom);
             } else {
                 return pairZero;
             }

app/src/main/java/org/gnucash/android/export/ExportAsyncTask.java

@@ -148,15 +148,10 @@ protected Boolean doInBackground(ExportParams... params) {
             Crashlytics.logException(e);
             e.printStackTrace();
             if (mContext instanceof Activity) {
-                ((Activity)mContext).runOnUiThread(new Runnable() {
-                    @Override
-                    public void run() {
-                        Toast.makeText(mContext,
-                                mContext.getString(R.string.toast_export_error, mExportParams.getExportFormat().name())
-                                + "\n" + e.getMessage(),
-                                Toast.LENGTH_SHORT).show();
-                    }
-                });
+                ((Activity)mContext).runOnUiThread(() -> Toast.makeText(mContext,
+                        mContext.getString(R.string.toast_export_error, mExportParams.getExportFormat().name())
+                        + "\n" + e.getMessage(),
+                        Toast.LENGTH_SHORT).show());
             }
             return false;
         }

app/src/main/java/org/gnucash/android/export/ExportFormat.java

@@ -15,6 +15,8 @@
  */
 package org.gnucash.android.export;
 
+import androidx.annotation.NonNull;
+
 /**
  * Enumeration of the different export formats supported by the application
 * @author Ngewi Fet <[email protected]>
@@ -55,6 +57,7 @@ public String getExtension(){
         }
     }
 
+    @NonNull
     @Override
     public String toString() {
         return mDescription;

app/src/main/java/org/gnucash/android/export/ExportParams.java

@@ -23,6 +23,8 @@
 
 import java.sql.Timestamp;
 
+import androidx.annotation.NonNull;
+
 /**
  * Encapsulation of the parameters used for exporting transactions.
  * The parameters are determined by the user in the export dialog and are then transmitted to the asynchronous task which
@@ -190,6 +192,7 @@ public void setCsvSeparator(char separator) {
         mCsvSeparator = separator;
     }
 
+    @NonNull
     @Override
     public String toString() {
         return "Export all transactions created since " + TimestampHelper.getUtcStringFromTimestamp(mExportStartTime) + " UTC"

app/src/main/java/org/gnucash/android/importer/ImportAsyncTask.java

@@ -86,14 +86,9 @@ protected Boolean doInBackground(Uri... uris) {
 
             final String err_msg = exception.getLocalizedMessage();
             Crashlytics.log(err_msg);
-            mContext.runOnUiThread(new Runnable() {
-                @Override
-                public void run() {
-                    Toast.makeText(mContext,
-                            mContext.getString(R.string.toast_error_importing_accounts) + "\n" + err_msg,
-                            Toast.LENGTH_LONG).show();
-                }
-            });
+            mContext.runOnUiThread(() -> Toast.makeText(mContext,
+                    mContext.getString(R.string.toast_error_importing_accounts) + "\n" + err_msg,
+                    Toast.LENGTH_LONG).show());
 
             return false;
         }

app/src/main/java/org/gnucash/android/model/Commodity.java

@@ -18,6 +18,8 @@
 import org.gnucash.android.app.GnuCashApplication;
 import org.gnucash.android.db.adapter.CommoditiesDbAdapter;
 
+import androidx.annotation.NonNull;
+
 /**
  * Commodities are the currencies used in the application.
  * At the moment only ISO4217 currencies are supported
@@ -190,6 +192,7 @@ public void setQuoteFlag(int quoteFlag) {
         this.mQuoteFlag = quoteFlag;
     }
 
+    @NonNull
     @Override
     /**
      * Returns the full name of the currency, or the currency code if there is no full name

app/src/main/java/org/gnucash/android/model/Money.java

@@ -450,7 +450,8 @@ public String toLocaleString(){
 	 * to the default locale
 	 * @return String representation of the amount formatted with default locale
 	 */
-    @Override
+    @NonNull
+	@Override
 	public String toString() {
 		return formattedString(Locale.getDefault());
 	}
@@ -506,7 +507,7 @@ public boolean isAmountZero() {
 		return mAmount.compareTo(BigDecimal.ZERO) == 0;
 	}
 
-	public class CurrencyMismatchException extends IllegalArgumentException{
+	public static class CurrencyMismatchException extends IllegalArgumentException{
 		@Override
 		public String getMessage() {
 			return "Cannot perform operation on Money instances with different currencies";

app/src/main/java/org/gnucash/android/model/Price.java

@@ -8,6 +8,8 @@
 import java.text.DecimalFormat;
 import java.text.NumberFormat;
 
+import androidx.annotation.NonNull;
+
 /**
  * Model for commodity prices
  */
@@ -150,6 +152,7 @@ private void reduce() {
      *
      * <p>Example: "0.123456"
      */
+    @NonNull
     @Override
     public String toString() {
         BigDecimal numerator = new BigDecimal(mValueNum);

app/src/main/java/org/gnucash/android/model/ScheduledAction.java

@@ -593,6 +593,7 @@ public static ScheduledAction parseScheduledAction(Transaction transaction, long
         return scheduledAction;
     }
 
+    @NonNull
     @Override
     public String toString() {
         return mActionType.name() + " - " + getRepeatString();

app/src/main/java/org/gnucash/android/model/Split.java

@@ -376,6 +376,7 @@ public void setReconcileDate(Timestamp reconcileDate) {
         this.mReconcileDate = reconcileDate;
     }
 
+    @NonNull
     @Override
     public String toString() {