Merge pull request #38 from brarcher/import-export

Add support for backing up cards to CSV file on external storage

.travis.yml

@@ -19,7 +19,7 @@ android:
     # if you need to run emulator(s) during your tests
     - sys-img-x86-android-17
 
-script: gradle build lint findbugs test
+script: ./gradlew build lint findbugs test
 
 after_failure:
 - cat app/build/outputs/lint-results.xml

app/build.gradle

@@ -39,6 +39,7 @@ dependencies {
     compile 'com.android.support:design:23.1.1'
     compile 'com.journeyapps:zxing-android-embedded:3.2.0@aar'
     compile 'com.google.zxing:core:3.2.1'
+    compile 'org.apache.commons:commons-csv:1.2'
     testCompile 'junit:junit:4.12'
     testCompile "org.robolectric:robolectric:3.0"
 }

app/src/main/AndroidManifest.xml

@@ -5,7 +5,8 @@
     <uses-permission
         android:name="android.permission.CAMERA"/>
     <uses-permission
-        android:maxSdkVersion="18"
+        android:name="android.permission.READ_EXTERNAL_STORAGE"/>
+    <uses-permission
         android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
 
     <uses-feature
@@ -37,6 +38,12 @@
             android:configChanges="orientation|screenSize"
             android:windowSoftInputMode="stateHidden"
             android:parentActivityName="protect.card_locker.MainActivity"/>
+        <activity
+            android:name=".ImportExportActivity"
+            android:label="@string/importExport"
+            android:configChanges="orientation|screenSize"
+            android:theme="@style/AppTheme.NoActionBar"
+            android:parentActivityName=".MainActivity"/>
     </application>
 
 </manifest>

app/src/main/java/protect/card_locker/CsvDatabaseExporter.java

@@ -0,0 +1,50 @@
+package protect.card_locker;
+
+import android.database.Cursor;
+
+import org.apache.commons.csv.CSVFormat;
+import org.apache.commons.csv.CSVPrinter;
+
+import java.io.IOException;
+import java.io.OutputStreamWriter;
+
+/**
+ * Class for exporting the database into CSV (Comma Separate Values)
+ * format.
+ */
+public class CsvDatabaseExporter implements DatabaseExporter
+{
+    public void exportData(DBHelper db, OutputStreamWriter output) throws IOException, InterruptedException
+    {
+        CSVPrinter printer = new CSVPrinter(output, CSVFormat.RFC4180);
+
+        // Print the header
+        printer.printRecord(DBHelper.LoyaltyCardDbIds.ID,
+                DBHelper.LoyaltyCardDbIds.STORE,
+                DBHelper.LoyaltyCardDbIds.NOTE,
+                DBHelper.LoyaltyCardDbIds.CARD_ID,
+                DBHelper.LoyaltyCardDbIds.BARCODE_TYPE);
+
+        Cursor cursor = db.getLoyaltyCardCursor();
+
+        while(cursor.moveToNext())
+        {
+            LoyaltyCard card = LoyaltyCard.toLoyaltyCard(cursor);
+
+            printer.printRecord(card.id,
+                    card.store,
+                    card.note,
+                    card.cardId,
+                    card.barcodeType);
+
+            if(Thread.currentThread().isInterrupted())
+            {
+                throw new InterruptedException();
+            }
+        }
+
+        cursor.close();
+
+        printer.close();
+    }
+}

app/src/main/java/protect/card_locker/CsvDatabaseImporter.java

@@ -0,0 +1,135 @@
+package protect.card_locker;
+
+import android.database.sqlite.SQLiteDatabase;
+
+import org.apache.commons.csv.CSVFormat;
+import org.apache.commons.csv.CSVParser;
+import org.apache.commons.csv.CSVRecord;
+
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+/**
+ * Class for importing a database from CSV (Comma Separate Values)
+ * formatted data.
+ *
+ * The database's loyalty cards are expected to appear in the CSV data.
+ * A header is expected for the each table showing the names of the columns.
+ */
+public class CsvDatabaseImporter implements DatabaseImporter
+{
+    public void importData(DBHelper db, InputStreamReader input) throws IOException, FormatException, InterruptedException
+    {
+        final CSVParser parser = new CSVParser(input, CSVFormat.RFC4180.withHeader());
+
+        SQLiteDatabase database = db.getWritableDatabase();
+        database.beginTransaction();
+
+        try
+        {
+            for (CSVRecord record : parser)
+            {
+                importLoyaltyCard(database, db, record);
+
+                if(Thread.currentThread().isInterrupted())
+                {
+                    throw new InterruptedException();
+                }
+            }
+
+            parser.close();
+            database.setTransactionSuccessful();
+        }
+        catch(IllegalArgumentException e)
+        {
+            throw new FormatException("Issue parsing CSV data", e);
+        }
+        finally
+        {
+            database.endTransaction();
+            database.close();
+        }
+    }
+
+    /**
+     * Extract a string from the items array. The index into the array
+     * is determined by looking up the index in the fields map using the
+     * "key" as the key. If no such key exists, defaultValue is returned
+     * if it is not null. Otherwise, a FormatException is thrown.
+     */
+    private String extractString(String key, CSVRecord record, String defaultValue)
+            throws FormatException
+    {
+        String toReturn = defaultValue;
+
+        if(record.isMapped(key))
+        {
+            toReturn = record.get(key);
+        }
+        else
+        {
+            if(defaultValue == null)
+            {
+                throw new FormatException("Field not used but expected: " + key);
+            }
+        }
+
+        return toReturn;
+    }
+
+    /**
+     * Extract an integer from the items array. The index into the array
+     * is determined by looking up the index in the fields map using the
+     * "key" as the key. If no such key exists, or the data is not a valid
+     * int, a FormatException is thrown.
+     */
+    private int extractInt(String key, CSVRecord record)
+            throws FormatException
+    {
+        if(record.isMapped(key) == false)
+        {
+            throw new FormatException("Field not used but expected: " + key);
+        }
+
+        try
+        {
+            return Integer.parseInt(record.get(key));
+        }
+        catch(NumberFormatException e)
+        {
+            throw new FormatException("Failed to parse field: " + key, e);
+        }
+    }
+
+    /**
+     * Import a single loyalty card into the database using the given
+     * session.
+     */
+    private void importLoyaltyCard(SQLiteDatabase database, DBHelper helper, CSVRecord record)
+            throws IOException, FormatException
+    {
+        int id = extractInt(DBHelper.LoyaltyCardDbIds.ID, record);
+
+        String store = extractString(DBHelper.LoyaltyCardDbIds.STORE, record, "");
+        if(store.isEmpty())
+        {
+            throw new FormatException("No store listed, but is required");
+        }
+
+        String note = extractString(DBHelper.LoyaltyCardDbIds.NOTE, record, "");
+
+        String cardId = extractString(DBHelper.LoyaltyCardDbIds.CARD_ID, record, "");
+        if(cardId.isEmpty())
+        {
+            throw new FormatException("No card ID listed, but is required");
+        }
+
+        String barcodeType = extractString(DBHelper.LoyaltyCardDbIds.BARCODE_TYPE, record, "");
+        if(barcodeType.isEmpty())
+        {
+            throw new FormatException("No barcode type listed, but is required");
+        }
+
+        helper.insertLoyaltyCard(database, id, store, note, cardId, barcodeType);
+    }
+}

app/src/main/java/protect/card_locker/DBHelper.java

@@ -64,6 +64,20 @@ public class DBHelper extends SQLiteOpenHelper
         return (newId != -1);
     }
 
+    public boolean insertLoyaltyCard(final SQLiteDatabase db, final int id,
+                                     final String store, final String note, final String cardId,
+                                     final String barcodeType)
+    {
+        ContentValues contentValues = new ContentValues();
+        contentValues.put(LoyaltyCardDbIds.ID, id);
+        contentValues.put(LoyaltyCardDbIds.STORE, store);
+        contentValues.put(LoyaltyCardDbIds.NOTE, note);
+        contentValues.put(LoyaltyCardDbIds.CARD_ID, cardId);
+        contentValues.put(LoyaltyCardDbIds.BARCODE_TYPE, barcodeType);
+        final long newId = db.insert(LoyaltyCardDbIds.TABLE, null, contentValues);
+        return (newId != -1);
+    }
+
 
     public boolean updateLoyaltyCard(final int id, final String store, final String note,
                                      final String cardId, final String barcodeType)

app/src/main/java/protect/card_locker/DataFormat.java

@@ -0,0 +1,8 @@
+package protect.card_locker;
+
+public enum DataFormat
+{
+    CSV,
+
+    ;
+}

app/src/main/java/protect/card_locker/DatabaseExporter.java

@@ -0,0 +1,17 @@
+package protect.card_locker;
+
+import java.io.IOException;
+import java.io.OutputStreamWriter;
+
+/**
+ * Interface for a class which can export the contents of the database
+ * in a given format.
+ */
+public interface DatabaseExporter
+{
+    /**
+     * Export the database to the output stream in a given format.
+     * @throws IOException
+     */
+    void exportData(DBHelper db, OutputStreamWriter output) throws IOException, InterruptedException;
+}

app/src/main/java/protect/card_locker/DatabaseImporter.java

@@ -0,0 +1,19 @@
+package protect.card_locker;
+
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+/**
+ * Interface for a class which can import the contents of a stream
+ * into the database.
+ */
+public interface DatabaseImporter
+{
+    /**
+     * Import data from the input stream in a given format into
+     * the database.
+     * @throws IOException
+     * @throws FormatException
+     */
+    void importData(DBHelper db, InputStreamReader input) throws IOException, FormatException, InterruptedException;
+}

app/src/main/java/protect/card_locker/FormatException.java

@@ -0,0 +1,19 @@
+package protect.card_locker;
+
+/**
+ * Exception thrown when something unexpected is
+ * encountered with the format of data being
+ * imported or exported.
+ */
+public class FormatException extends Exception
+{
+    public FormatException(String message)
+    {
+        super(message);
+    }
+
+    public FormatException(String message, Exception rootCause)
+    {
+        super(message, rootCause);
+    }
+}

app/src/main/java/protect/card_locker/ImportExportActivity.java

@@ -0,0 +1,131 @@
+package protect.card_locker;
+
+import android.Manifest;
+import android.content.pm.PackageManager;
+import android.os.AsyncTask;
+import android.os.Bundle;
+import android.support.v4.app.ActivityCompat;
+import android.support.v4.content.ContextCompat;
+import android.support.v7.app.ActionBar;
+import android.support.v7.app.AppCompatActivity;
+import android.support.v7.widget.Toolbar;
+import android.view.View;
+import android.widget.Button;
+import android.widget.Toast;
+
+public class ImportExportActivity extends AppCompatActivity
+{
+    private static final int PERMISSIONS_EXTERNAL_STORAGE_IMPORT = 1;
+    private static final int PERMISSIONS_EXTERNAL_STORAGE_EXPORT = 2;
+
+    ImportExportTask importExporter;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState)
+    {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.import_export_activity);
+        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
+        setSupportActionBar(toolbar);
+        ActionBar actionBar = getSupportActionBar();
+        if(actionBar != null)
+        {
+            actionBar.setDisplayHomeAsUpEnabled(true);
+        }
+
+        Button importButton = (Button)findViewById(R.id.importButton);
+        importButton.setOnClickListener(new View.OnClickListener()
+        {
+            @Override
+            public void onClick(View v)
+            {
+                if (ContextCompat.checkSelfPermission(ImportExportActivity.this,
+                        Manifest.permission.READ_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED)
+                {
+                    startImport();
+                }
+                else
+                {
+                    ActivityCompat.requestPermissions(ImportExportActivity.this,
+                            new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},
+                            PERMISSIONS_EXTERNAL_STORAGE_IMPORT);
+                }
+            }
+        });
+
+        Button exportButton = (Button)findViewById(R.id.exportButton);
+        exportButton.setOnClickListener(new View.OnClickListener()
+        {
+            @Override
+            public void onClick(View v)
+            {
+                if (ContextCompat.checkSelfPermission(ImportExportActivity.this,
+                        Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED)
+                {
+                    startExport();
+                }
+                else
+                {
+                    ActivityCompat.requestPermissions(ImportExportActivity.this,
+                            new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
+                            PERMISSIONS_EXTERNAL_STORAGE_EXPORT);
+                }
+            }
+        });
+    }
+
+    private void startImport()
+    {
+        importExporter = new ImportExportTask(ImportExportActivity.this,
+                true, DataFormat.CSV);
+        importExporter.execute();
+    }
+
+    private void startExport()
+    {
+        importExporter = new ImportExportTask(ImportExportActivity.this,
+                false, DataFormat.CSV);
+        importExporter.execute();
+    }
+
+    @Override
+    public void onRequestPermissionsResult(int requestCode, String permissions[], int[] grantResults)
+    {
+        if(requestCode == PERMISSIONS_EXTERNAL_STORAGE_IMPORT ||
+           requestCode == PERMISSIONS_EXTERNAL_STORAGE_EXPORT)
+        {
+            // If request is cancelled, the result arrays are empty.
+            if (grantResults.length > 0 &&
+                    grantResults[0] == PackageManager.PERMISSION_GRANTED)
+            {
+                // permission was granted.
+                if(requestCode == PERMISSIONS_EXTERNAL_STORAGE_IMPORT)
+                {
+                    startImport();
+                }
+                else
+                {
+                    startExport();
+                }
+            }
+            else
+            {
+                // External storage permission rejected, inform user that
+                // import/export is prevented
+                Toast.makeText(getApplicationContext(), R.string.noExternalStoragePermissionError,
+                        Toast.LENGTH_LONG).show();
+            }
+
+        }
+    }
+
+    @Override
+    protected void onDestroy()
+    {
+        if(importExporter != null && importExporter.getStatus() != AsyncTask.Status.RUNNING)
+        {
+            importExporter.cancel(true);
+        }
+        super.onDestroy();
+    }
+}

app/src/main/java/protect/card_locker/ImportExportTask.java

@@ -0,0 +1,146 @@
+package protect.card_locker;
+
+import android.app.Activity;
+import android.app.ProgressDialog;
+import android.content.DialogInterface;
+import android.os.AsyncTask;
+import android.os.Environment;
+import android.util.Log;
+import android.widget.Toast;
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
+import java.nio.charset.Charset;
+
+class ImportExportTask extends AsyncTask<Void, Void, Void>
+{
+    private static final String TAG = "BudgetWatch";
+
+    private static final String TARGET_FILE = "LoyaltyCardLocker.csv";
+
+    private Activity activity;
+    private boolean doImport;
+    private DataFormat format;
+
+    private ProgressDialog progress;
+
+    public ImportExportTask(Activity activity, boolean doImport, DataFormat format)
+    {
+        super();
+        this.activity = activity;
+        this.doImport = doImport;
+        this.format = format;
+    }
+
+    private void toastWithArg(int stringId, String argument)
+    {
+        final String template = activity.getResources().getString(stringId);
+        final String message = String.format(template, argument);
+
+        activity.runOnUiThread(new Runnable()
+        {
+            @Override
+            public void run()
+            {
+                Toast.makeText(activity, message, Toast.LENGTH_LONG).show();
+            }
+        });
+    }
+
+    private void performImport(File importFile, DBHelper db)
+    {
+        if(importFile.exists() == false)
+        {
+            toastWithArg(R.string.fileMissing, importFile.getAbsolutePath());
+            return;
+        }
+
+        boolean result = false;
+
+        try
+        {
+            FileInputStream fileReader = new FileInputStream(importFile);
+            InputStreamReader reader = new InputStreamReader(fileReader, Charset.forName("UTF-8"));
+            result = MultiFormatImporter.importData(db, reader, format);
+            reader.close();
+        }
+        catch(IOException e)
+        {
+            Log.e(TAG, "Unable to import file", e);
+        }
+
+        int messageId = result ? R.string.importedFrom : R.string.importFailed;
+        toastWithArg(messageId, importFile.getAbsolutePath());
+    }
+
+    private void performExport(File exportFile, DBHelper db)
+    {
+        boolean result = false;
+
+        try
+        {
+            FileOutputStream fileWriter = new FileOutputStream(exportFile);
+            OutputStreamWriter writer = new OutputStreamWriter(fileWriter, Charset.forName("UTF-8"));
+            result = MultiFormatExporter.exportData(db, writer, format);
+            writer.close();
+        }
+        catch (IOException e)
+        {
+            Log.e(TAG, "Unable to export file", e);
+        }
+
+        int messageId = result ? R.string.exportedTo : R.string.exportFailed;
+        toastWithArg(messageId, exportFile.getAbsolutePath());
+    }
+
+    protected void onPreExecute()
+    {
+        progress = new ProgressDialog(activity);
+        progress.setTitle(doImport ? R.string.importing : R.string.exporting);
+
+        progress.setOnDismissListener(new DialogInterface.OnDismissListener()
+        {
+            @Override
+            public void onDismiss(DialogInterface dialog)
+            {
+                ImportExportTask.this.cancel(true);
+            }
+        });
+
+        progress.show();
+    }
+
+    protected Void doInBackground(Void... nothing)
+    {
+        final File sdcardDir = Environment.getExternalStorageDirectory();
+        final File importExportFile = new File(sdcardDir, TARGET_FILE);
+        final DBHelper db = new DBHelper(activity);
+
+        if(doImport)
+        {
+            performImport(importExportFile, db);
+        }
+        else
+        {
+            performExport(importExportFile, db);
+        }
+
+        return null;
+    }
+
+    protected void onPostExecute(Void result)
+    {
+        progress.dismiss();
+        Log.i(TAG, (doImport ? "Import" : "Export") + " Complete");
+    }
+
+    protected void onCancelled()
+    {
+        progress.dismiss();
+        Log.i(TAG, (doImport ? "Import" : "Export") + " Cancelled");
+    }
+}

app/src/main/java/protect/card_locker/MainActivity.java

@@ -1,19 +1,29 @@
 package protect.card_locker;
 
+import android.content.DialogInterface;
 import android.content.Intent;
+import android.content.pm.PackageInfo;
+import android.content.pm.PackageManager;
 import android.database.Cursor;
 import android.os.Bundle;
+import android.support.v7.app.AlertDialog;
 import android.support.v7.app.AppCompatActivity;
 import android.support.v7.widget.Toolbar;
+import android.util.Log;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.View;
+import android.webkit.WebView;
 import android.widget.AdapterView;
 import android.widget.ListView;
 import android.widget.TextView;
 
+import java.util.Calendar;
+
 public class MainActivity extends AppCompatActivity
 {
+    private static final String TAG = "LoyaltyCardLocker";
+
     @Override
     protected void onCreate(Bundle savedInstanceState)
     {
@@ -92,6 +102,88 @@ public class MainActivity extends AppCompatActivity
             return true;
         }
 
+        if(id == R.id.action_import_export)
+        {
+            Intent i = new Intent(getApplicationContext(), ImportExportActivity.class);
+            startActivity(i);
+            return true;
+        }
+
+        if(id == R.id.action_about)
+        {
+            displayAboutDialog();
+            return true;
+        }
+
         return super.onOptionsItemSelected(item);
     }
+
+    private void displayAboutDialog()
+    {
+        final String[][] USED_LIBRARIES = new String[][]
+        {
+            new String[] {"Commons CSV", "https://commons.apache.org/proper/commons-csv/"},
+            new String[] {"ZXing", "https://github.com/zxing/zxing"},
+            new String[] {"ZXing Android Embedded", "https://github.com/journeyapps/zxing-android-embedded"},
+        };
+
+        StringBuilder libs = new StringBuilder().append("<ul>");
+        for (String[] library : USED_LIBRARIES)
+        {
+            libs.append("<li><a href=\"").append(library[1]).append("\">").append(library[0]).append("</a></li>");
+        }
+        libs.append("</ul>");
+
+        String appName = getString(R.string.app_name);
+        int year = Calendar.getInstance().get(Calendar.YEAR);
+
+        String version = "?";
+        try
+        {
+            PackageInfo pi = getPackageManager().getPackageInfo(getPackageName(), 0);
+            version = pi.versionName;
+        }
+        catch (PackageManager.NameNotFoundException e)
+        {
+            Log.w(TAG, "Package name not found", e);
+        }
+
+        WebView wv = new WebView(this);
+        String html =
+            "<meta http-equiv=\"content-type\" content=\"text/html; charset=utf-8\" />" +
+            "<img src=\"file:///android_res/mipmap/ic_launcher.png\" alt=\"" + appName + "\"/>" +
+            "<h1>" +
+            String.format(getString(R.string.about_title_fmt),
+                    "<a href=\"" + getString(R.string.app_webpage_url)) + "\">" +
+            appName +
+            "</a>" +
+            "</h1><p>" +
+            appName +
+            " " +
+            String.format(getString(R.string.debug_version_fmt), version) +
+            "</p><p>" +
+            String.format(getString(R.string.app_revision_fmt),
+                    "<a href=\"" + getString(R.string.app_revision_url) + "\">" +
+                            getString(R.string.app_revision_url) +
+                            "</a>") +
+            "</p><hr/><p>" +
+            String.format(getString(R.string.app_copyright_fmt), year) +
+            "</p><hr/><p>" +
+            getString(R.string.app_license) +
+            "</p><hr/><p>" +
+            String.format(getString(R.string.app_libraries), appName, libs.toString());
+
+        wv.loadDataWithBaseURL("file:///android_res/drawable/", html, "text/html", "utf-8", null);
+        new AlertDialog.Builder(this)
+            .setView(wv)
+            .setCancelable(true)
+            .setPositiveButton(R.string.ok, new DialogInterface.OnClickListener()
+            {
+                public void onClick(DialogInterface dialog, int which)
+                {
+                    dialog.dismiss();
+                }
+            })
+            .show();
+    }
 }

app/src/main/java/protect/card_locker/MultiFormatExporter.java

@@ -0,0 +1,57 @@
+package protect.card_locker;
+
+import android.util.Log;
+
+import java.io.IOException;
+import java.io.OutputStreamWriter;
+
+public class MultiFormatExporter
+{
+    private static final String TAG = "LoyaltyCardLocker";
+
+    /**
+     * Attempts to export data to the output stream in the
+     * given format, if possible.
+     *
+     * The output stream is closed on success.
+     *
+     * @return true if the database was successfully exported,
+     * false otherwise. If false, partial data may have been
+     * written to the output stream, and it should be discarded.
+     */
+    public static boolean exportData(DBHelper db, OutputStreamWriter output, DataFormat format)
+    {
+        DatabaseExporter exporter = null;
+
+        switch(format)
+        {
+            case CSV:
+                exporter = new CsvDatabaseExporter();
+                break;
+        }
+
+        if(exporter != null)
+        {
+            try
+            {
+                exporter.exportData(db, output);
+                return true;
+            }
+            catch(IOException e)
+            {
+                Log.e(TAG, "Failed to export data", e);
+            }
+            catch(InterruptedException e)
+            {
+                Log.e(TAG, "Failed to export data", e);
+            }
+
+            return false;
+        }
+        else
+        {
+            Log.e(TAG, "Unsupported data format exported: " + format.name());
+            return false;
+        }
+    }
+}

app/src/main/java/protect/card_locker/MultiFormatImporter.java

@@ -0,0 +1,62 @@
+package protect.card_locker;
+
+import android.util.Log;
+
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+public class MultiFormatImporter
+{
+    private static final String TAG = "LoyaltyCardLocker";
+
+    /**
+     * Attempts to import data from the input stream of the
+     * given format into the database.
+     *
+     * The input stream is not closed, and doing so is the
+     * responsibility of the caller.
+     *
+     * @return true if the database was successfully imported,
+     * false otherwise. If false, no data was written to
+     * the database.
+     */
+    public static boolean importData(DBHelper db, InputStreamReader input, DataFormat format)
+    {
+        DatabaseImporter importer = null;
+
+        switch(format)
+        {
+            case CSV:
+                importer = new CsvDatabaseImporter();
+                break;
+        }
+
+        if(importer != null)
+        {
+            try
+            {
+                importer.importData(db, input);
+                return true;
+            }
+            catch(IOException e)
+            {
+                Log.e(TAG, "Failed to input data", e);
+            }
+            catch(FormatException e)
+            {
+                Log.e(TAG, "Failed to input data", e);
+            }
+            catch(InterruptedException e)
+            {
+                Log.e(TAG, "Failed to input data", e);
+            }
+
+            return false;
+        }
+        else
+        {
+            Log.e(TAG, "Unsupported data format imported: " + format.name());
+            return false;
+        }
+    }
+}

app/src/main/res/layout/import_export_activity.xml

@@ -0,0 +1,54 @@
+<?xml version="1.0" encoding="utf-8"?>
+<android.support.design.widget.CoordinatorLayout xmlns:android="http://schemas.android.com/apk/res/android"
+                                                 xmlns:app="http://schemas.android.com/apk/res-auto"
+                                                 android:layout_width="match_parent"
+                                                 android:layout_height="match_parent"
+                                                 android:fitsSystemWindows="true">
+
+    <android.support.design.widget.AppBarLayout
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:theme="@style/AppTheme.AppBarOverlay">
+
+        <android.support.v7.widget.Toolbar
+            android:id="@+id/toolbar"
+            android:layout_width="match_parent"
+            android:layout_height="?attr/actionBarSize"
+            android:background="?attr/colorPrimary"
+            app:popupTheme="@style/AppTheme.PopupOverlay" />
+
+    </android.support.design.widget.AppBarLayout>
+
+    <LinearLayout android:orientation="vertical"
+                  android:layout_width="fill_parent"
+                  android:layout_height="fill_parent"
+                  app:layout_behavior="@string/appbar_scrolling_view_behavior">
+        <TextView
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:padding="20dp"
+            android:textSize="20sp"
+            android:layout_gravity="center"
+            android:text="@string/importExportHelp"/>
+
+        <LinearLayout android:orientation="horizontal"
+                      android:layout_width="fill_parent"
+                      android:layout_height="fill_parent">
+            <Button
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="@string/importName"
+                android:layout_weight="1.0"
+                android:id="@+id/importButton"/>
+            <Button
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="@string/exportName"
+                android:layout_weight="1.0"
+                android:id="@+id/exportButton"/>
+        </LinearLayout>
+
+    </LinearLayout>
+
+
+</android.support.design.widget.CoordinatorLayout>

app/src/main/res/menu/main_menu.xml

@@ -7,4 +7,13 @@
         android:icon="@drawable/ic_add_white_24dp"
         android:title="@string/action_add"
         app:showAsAction="always"/>
+    <item
+        android:id="@+id/action_import_export"
+        android:icon="@drawable/ic_import_export_white_24dp"
+        android:title="@string/importExport"
+        app:showAsAction="ifRoom"/>
+    <item
+        android:id="@+id/action_about"
+        android:title="@string/about"
+        app:showAsAction="never"/>
 </menu>

app/src/main/res/values-it/strings.xml

@@ -1,4 +1,6 @@
-<resources>
+<resources
+    xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+
     <string name="app_name">Carte fedeltà</string>
     <string name="action_add">Aggiungi</string>
 
@@ -26,4 +28,25 @@
 
     <string name="cardIdFormat">%1$s: %2$s</string>
     <string name="note">Note</string>
+
+    <string name="importExport">Importa/Esporta</string>
+    <string name="importName">Importa</string>
+    <string name="exportName">Esporta</string>
+    <string name="importExportHelp">I dati sono stati importati in o esportati dal file LoyaltyCardLocker.csv sulla memoria esterna</string>
+    <string name="importedFrom">Importato da: %1$s</string>
+    <string name="exportedTo">Esportato in: %1$s</string>
+    <string name="fileMissing">File mancante: %1$s</string>
+    <string name="importFailed">Impossibile importare: %1$s</string>
+    <string name="exportFailed">Impossibile esportare: %1$s</string>
+    <string name="importing">Importazione in corso&#8230;</string>
+    <string name="exporting">Esportazione in corso&#8230;</string>
+    <string name="noExternalStoragePermissionError">Impossibile importare o esportare i dati senza il permesso per l\'uso della memoria esterna.</string>
+    <string name="about">Informazioni</string>
+    <string name="app_copyright_fmt">Copyright 2016-<xliff:g>%s</xliff:g> Branden Archer</string>
+    <string name="app_license">Pubblicato sotto licenza GPLv3.</string>
+    <string name="about_title_fmt">Informazioni su <xliff:g id="app_name">%s</xliff:g></string>
+    <string name="debug_version_fmt">Versione: <xliff:g id="version">%s</xliff:g></string>
+    <string name="app_revision_fmt">Informazione sulla revisione: <xliff:g id="app_revision_url">%s</xliff:g></string>
+    <string name="app_libraries"><xliff:g id="app_name">%s</xliff:g> usa le seguenti librerie di terze parti: <xliff:g id="app_libraries_list">%s</xliff:g></string>
+    <string name="ok">Ok</string>
 </resources>

app/src/main/res/values-nl/strings.xml

@@ -1,4 +1,6 @@
-<resources>
+<resources
+    xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+
     <string name="app_name">Klantenkaartenkluis</string>
     <string name="action_add">Voeg toe</string>
 
@@ -26,4 +28,25 @@
 
     <string name="cardIdFormat">%1$s: %2$s</string>
     <string name="note">Notitie</string>
+
+    <string name="importExport">Importeer/Exporteer</string>
+    <string name="importName">Importeer</string>
+    <string name="exportName">Exporteer</string>
+    <string name="importExportHelp">Data is geïmporteerd van of geëxporteerd naar LoyaltyCardLocker.csv op externe opslag</string>
+    <string name="importedFrom">Geïmporteerd van: %1$s</string>
+    <string name="exportedTo">Geëxporteerd naar: %1$s</string>
+    <string name="fileMissing">Bestand niet gevonden: %1$s</string>
+    <string name="importFailed">Importeren mislukte: %1$s</string>
+    <string name="exportFailed">Exporteren mislukte: %1$s</string>
+    <string name="importing">Importerende&#8230;</string>
+    <string name="exporting">Exporterende&#8230;</string>
+    <string name="noExternalStoragePermissionError">Niet mogelijk te importeren of exporteren zonder rechten op externe opslag</string>
+    <string name="about">Over</string>
+    <string name="app_copyright_fmt">Auteursrecht 2016-<xliff:g>%s</xliff:g> Branden Archer</string>
+    <string name="app_license">Gelicenseerd met GPLv3.</string>
+    <string name="about_title_fmt">Over <xliff:g id="app_name">%s</xliff:g></string>
+    <string name="debug_version_fmt">Versie: <xliff:g id="version">%s</xliff:g></string>
+    <string name="app_revision_fmt">Revisieïnformatie: <xliff:g id="app_revision_url">%s</xliff:g></string>
+    <string name="app_libraries"><xliff:g id="app_name">%s</xliff:g> gebruikt de volgende bibliotheken van derden: <xliff:g id="app_libraries_list">%s</xliff:g></string>
+    <string name="ok">Oké</string>
 </resources>

app/src/main/res/values/constants.xml

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="app_revision_url" translatable="false">https://github.com/brarcher/loyalty-card-locker/releases</string>
+    <string name="app_webpage_url" translatable="false">https://github.com/brarcher/loyalty-card-locker</string>
+</resources>

app/src/main/res/values/strings.xml

@@ -1,4 +1,6 @@
-<resources>
+<resources
+    xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
+
     <string name="app_name">Loyalty Card Locker</string>
     <string name="action_add">Add</string>
 
@@ -14,6 +16,7 @@
     <string name="capture">Capture Card</string>
     <string name="edit">Edit</string>
     <string name="delete">Delete</string>
+    <string name="ok">OK</string>
 
     <string name="editCardTitle">Edit Loyalty Card</string>
     <string name="addCardTitle">Add Loyalty Card</string>
@@ -27,4 +30,25 @@
 
     <string name="cardIdFormat">%1$s: %2$s</string>
     <string name="storeNameAndNoteFormat" translatable="false">%1$s - %2$s</string>
+
+    <string name="importExport">Import/Export</string>
+    <string name="importName">Import</string>
+    <string name="exportName">Export</string>
+    <string name="importExportHelp">Data is imported to/exported from LoyaltyCardLocker.csv on external storage</string>
+    <string name="importedFrom">Imported from: %1$s</string>
+    <string name="exportedTo">Exported to: %1$s</string>
+    <string name="fileMissing">File missing: %1$s</string>
+    <string name="importFailed">Failed to import: %1$s</string>
+    <string name="exportFailed">Failed to export: %1$s</string>
+    <string name="importing">Importing&#8230;</string>
+    <string name="exporting">Exporting&#8230;</string>
+    <string name="noExternalStoragePermissionError">Unable to import or export cards without the external storage permission</string>
+
+    <string name="about">About</string>
+    <string name="app_copyright_fmt">Copyright 2016-<xliff:g>%s</xliff:g> Branden Archer</string>
+    <string name="app_license">Licensed under the GPLv3.</string>
+    <string name="about_title_fmt">About <xliff:g id="app_name">%s</xliff:g></string>
+    <string name="debug_version_fmt">Version: <xliff:g id="version">%s</xliff:g></string>
+    <string name="app_revision_fmt">Revision Information: <xliff:g id="app_revision_url">%s</xliff:g></string>
+    <string name="app_libraries"><xliff:g id="app_name">%s</xliff:g> uses the following third-party libraries: <xliff:g id="app_libraries_list">%s</xliff:g></string>
 </resources>

app/src/test/java/protect/card_locker/ImportExportTest.java

@@ -0,0 +1,242 @@
+package protect.card_locker;
+
+import android.app.Activity;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+
+import com.google.zxing.BarcodeFormat;
+
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.robolectric.Robolectric;
+import org.robolectric.RobolectricGradleTestRunner;
+import org.robolectric.annotation.Config;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
+import java.util.Calendar;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+@RunWith(RobolectricGradleTestRunner.class)
+@Config(constants = BuildConfig.class, sdk = 17)
+public class ImportExportTest
+{
+    private Activity activity;
+    private DBHelper db;
+    private long nowMs;
+    private long lastYearMs;
+    private final int MONTHS_PER_YEAR = 12;
+
+    private final String BARCODE_DATA = "428311627547";
+    private final String BARCODE_TYPE = BarcodeFormat.UPC_A.name();
+
+    @Before
+    public void setUp()
+    {
+        activity = Robolectric.setupActivity(MainActivity.class);
+        db = new DBHelper(activity);
+        nowMs = System.currentTimeMillis();
+
+        Calendar lastYear = Calendar.getInstance();
+        lastYear.set(Calendar.YEAR, lastYear.get(Calendar.YEAR)-1);
+        lastYearMs = lastYear.getTimeInMillis();
+    }
+
+    /**
+     * Add the given number of cards, each with
+     * an index in the store name.
+     * @param cardsToAdd
+     */
+    private void addLoyaltyCards(int cardsToAdd)
+    {
+        // Add in reverse order to test sorting
+        for(int index = cardsToAdd; index > 0; index--)
+        {
+            String storeName = String.format("store, \"%4d", index);
+            String note = String.format("note, \"%4d", index);
+            boolean result = db.insertLoyaltyCard(storeName, note, BARCODE_DATA, BARCODE_TYPE);
+            assertTrue(result);
+        }
+
+        assertEquals(cardsToAdd, db.getLoyaltyCardCount());
+    }
+
+    /**
+     * Check that all of the cards follow the pattern
+     * specified in addLoyaltyCards(), and are in sequential order
+     * where the smallest card's index is 1
+     */
+    private void checkLoyaltyCards()
+    {
+        Cursor cursor = db.getLoyaltyCardCursor();
+        int index = 1;
+
+        while(cursor.moveToNext())
+        {
+            LoyaltyCard card = LoyaltyCard.toLoyaltyCard(cursor);
+
+            String expectedStore = String.format("store, \"%4d", index);
+            String expectedNote = String.format("note, \"%4d", index);
+
+            assertEquals(expectedStore, card.store);
+            assertEquals(expectedNote, card.note);
+            assertEquals(BARCODE_DATA, card.cardId);
+            assertEquals(BARCODE_TYPE, card.barcodeType);
+
+            index++;
+        }
+        cursor.close();
+    }
+
+    /**
+     * Delete the contents of the database
+     */
+    private void clearDatabase()
+    {
+        SQLiteDatabase database = db.getWritableDatabase();
+        database.execSQL("delete from " + DBHelper.LoyaltyCardDbIds.TABLE);
+        database.close();
+
+        assertEquals(0, db.getLoyaltyCardCount());
+    }
+
+    @Test
+    public void multipleCardsExportImport() throws IOException
+    {
+        final int NUM_CARDS = 1000;
+
+        for(DataFormat format : DataFormat.values())
+        {
+            addLoyaltyCards(NUM_CARDS);
+
+            ByteArrayOutputStream outData = new ByteArrayOutputStream();
+            OutputStreamWriter outStream = new OutputStreamWriter(outData);
+
+            // Export data to CSV format
+            boolean result = MultiFormatExporter.exportData(db, outStream, format);
+            assertTrue(result);
+            outStream.close();
+
+            clearDatabase();
+
+            ByteArrayInputStream inData = new ByteArrayInputStream(outData.toByteArray());
+            InputStreamReader inStream = new InputStreamReader(inData);
+
+            // Import the CSV data
+            result = MultiFormatImporter.importData(db, inStream, DataFormat.CSV);
+            assertTrue(result);
+
+            assertEquals(NUM_CARDS, db.getLoyaltyCardCount());
+
+            checkLoyaltyCards();
+
+            // Clear the database for the next format under test
+            clearDatabase();
+        }
+    }
+
+    @Test
+    public void importExistingCardsNotReplace() throws IOException
+    {
+        final int NUM_CARDS = 1000;
+
+        for(DataFormat format : DataFormat.values())
+        {
+            addLoyaltyCards(NUM_CARDS);
+
+            ByteArrayOutputStream outData = new ByteArrayOutputStream();
+            OutputStreamWriter outStream = new OutputStreamWriter(outData);
+
+            // Export into CSV data
+            boolean result = MultiFormatExporter.exportData(db, outStream, format);
+            assertTrue(result);
+            outStream.close();
+
+            ByteArrayInputStream inData = new ByteArrayInputStream(outData.toByteArray());
+            InputStreamReader inStream = new InputStreamReader(inData);
+
+            // Import the CSV data on top of the existing database
+            result = MultiFormatImporter.importData(db, inStream, DataFormat.CSV);
+            assertTrue(result);
+
+            assertEquals(NUM_CARDS, db.getLoyaltyCardCount());
+
+            checkLoyaltyCards();
+
+            // Clear the database for the next format under test
+            clearDatabase();
+        }
+    }
+
+    @Test
+    public void corruptedImportNothingSaved() throws IOException
+    {
+        final int NUM_CARDS = 1000;
+
+        for(DataFormat format : DataFormat.values())
+        {
+            addLoyaltyCards(NUM_CARDS);
+
+            ByteArrayOutputStream outData = new ByteArrayOutputStream();
+            OutputStreamWriter outStream = new OutputStreamWriter(outData);
+
+            // Export data to CSV format
+            boolean result = MultiFormatExporter.exportData(db, outStream, format);
+            assertTrue(result);
+
+            clearDatabase();
+
+            String corruptEntry = "ThisStringIsLikelyNotPartOfAnyFormat";
+
+            ByteArrayInputStream inData = new ByteArrayInputStream((outData.toString() + corruptEntry).getBytes());
+            InputStreamReader inStream = new InputStreamReader(inData);
+
+            // Attempt to import the CSV data
+            result = MultiFormatImporter.importData(db, inStream, DataFormat.CSV);
+            assertEquals(false, result);
+
+            assertEquals(0, db.getLoyaltyCardCount());
+        }
+    }
+
+    @Test
+    public void useImportExportTask()
+    {
+        final int NUM_CARDS = 10;
+
+        for(DataFormat format : DataFormat.values())
+        {
+            addLoyaltyCards(NUM_CARDS);
+
+            // Export to whatever the default location is
+            ImportExportTask task = new ImportExportTask(activity, false, format);
+            task.execute();
+
+            // Actually run the task to completion
+            Robolectric.flushBackgroundThreadScheduler();
+
+            clearDatabase();
+
+            // Import everything back from the default location
+
+            task = new ImportExportTask(activity, true, format);
+            task.execute();
+
+            // Actually run the task to completion
+            Robolectric.flushBackgroundThreadScheduler();
+
+            assertEquals(NUM_CARDS, db.getLoyaltyCardCount());
+
+            checkLoyaltyCards();
+
+            // Clear the database for the next format under test
+            clearDatabase();
+        }
+    }
+}

app/src/test/java/protect/card_locker/MainActivityTest.java

@@ -50,9 +50,11 @@ public class MainActivityTest
         assertTrue(menu != null);
 
         // The settings and add button should be present
-        assertEquals(menu.size(), 1);
+        assertEquals(menu.size(), 3);
 
         assertEquals("Add", menu.findItem(R.id.action_add).getTitle().toString());
+        assertEquals("Import/Export", menu.findItem(R.id.action_import_export).getTitle().toString());
+        assertEquals("About", menu.findItem(R.id.action_about).getTitle().toString());
     }
 
     @Test

build.gradle

@@ -5,7 +5,7 @@ buildscript {
         jcenter()
     }
     dependencies {
-        classpath 'com.android.tools.build:gradle:1.5.0'
+        classpath 'com.android.tools.build:gradle:2.0.0'
 
         // NOTE: Do not place your application dependencies here; they belong
         // in the individual module build.gradle files

gradle/wrapper/gradle-wrapper.properties

@@ -1,6 +1,6 @@
-#Wed Oct 21 11:34:03 PDT 2015
+#Tue May 03 10:42:45 EDT 2016
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-2.8-all.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-2.10-all.zip