/*
* This source is part of the
* _____ ___ ____
* __ / / _ \/ _ | / __/___ _______ _
* / // / , _/ __ |/ _/_/ _ \/ __/ _ `/
* \___/_/|_/_/ |_/_/ (_)___/_/ \_, /
* /___/
* repository.
*
* Copyright (C) 2013-2015 Carmen Alvarez (c@rmen.ca)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package ca.rmen.android.networkmonitor.app.dbops.backend.export;
import android.content.Context;
import android.database.Cursor;
import android.net.Uri;
import java.io.File;
import java.io.IOException;
import java.util.Arrays;
import ca.rmen.android.networkmonitor.Constants;
import ca.rmen.android.networkmonitor.R;
import ca.rmen.android.networkmonitor.app.dbops.ProgressListener;
import ca.rmen.android.networkmonitor.app.dbops.backend.export.FormatterFactory.FormatterStyle;
import ca.rmen.android.networkmonitor.app.prefs.FilterPreferences;
import ca.rmen.android.networkmonitor.app.prefs.FilterPreferences.Selection;
import ca.rmen.android.networkmonitor.app.prefs.NetMonPreferences;
import ca.rmen.android.networkmonitor.app.prefs.SortPreferences;
import ca.rmen.android.networkmonitor.provider.NetMonColumns;
import ca.rmen.android.networkmonitor.provider.NetMonProvider;
import ca.rmen.android.networkmonitor.util.Log;
/**
* Export the Network Monitor data from the DB to a file in a table format.
*/
abstract class TableFileExport extends FileExport {
private static final String TAG = Constants.TAG + TableFileExport.class.getSimpleName();
private static final int THRESHOLD_LOW_MEMORY_PCT = 40;
private final FormatterStyle mFormatterStyle;
TableFileExport(Context context, File file, FormatterStyle formatterStyle) {
super(context, file);
mFormatterStyle = formatterStyle;
}
/**
* Do any preparation for the export, including writing the header with the
* column names.
*/
abstract void writeHeader(String[] columnNames) throws IOException;
/**
* Write a single row to the file.
*/
abstract void writeRow(int rowNumber, String[] cellValues);
/**
* Write the footer (if any) and do any cleanup after the export.
*/
abstract void writeFooter() throws IOException;
@Override
public void execute(ProgressListener listener) {
Log.v(TAG, "export");
export(0, listener);
}
/**
* @param recordCount export at most this number of records. If recordCount is 0 or less, all records will be exported.
* @return the file if it was correctly exported, null otherwise.
*/
public File export(int recordCount, ProgressListener listener) {
Log.v(TAG, "export " + (recordCount <= 0 ? "all" : recordCount) + " records");
String[] usedColumnNames = (String[]) NetMonPreferences.getInstance(mContext).getSelectedColumns().toArray();
Formatter formatter = FormatterFactory.getFormatter(mFormatterStyle, mContext);
// Order and filter the results based on the user's preferences.
SortPreferences sortPreferences = NetMonPreferences.getInstance(mContext).getSortPreferences();
Selection selection = FilterPreferences.getSelectionClause(mContext);
Uri uri = NetMonColumns.CONTENT_URI;
if (recordCount > 0)
uri = uri.buildUpon().appendQueryParameter(NetMonProvider.QUERY_PARAMETER_LIMIT, String.valueOf(recordCount)).build();
Cursor c = mContext.getContentResolver().query(uri, usedColumnNames, selection.selectionString, selection.selectionArgs,
sortPreferences.getOrderByClause());
if (c != null) {
try {
for (int i = 0; i < usedColumnNames.length; i++)
usedColumnNames[i] = NetMonColumns.getColumnLabel(mContext, usedColumnNames[i]);
Log.v(TAG, "Column names: " + Arrays.toString(usedColumnNames));
// Write the table rows to the file.
int rowsAvailable = c.getCount();
// Start writing to the file.
writeHeader(usedColumnNames);
while (c.moveToNext() && !isCanceled()) {
String[] cellValues = new String[c.getColumnCount()];
for (int i = 0; i < c.getColumnCount(); i++)
cellValues[i] = formatter.format(c, i);
writeRow(c.getPosition(), cellValues);
// Notify the listener of our progress (progress is 1-based)
if (listener != null) listener.onProgress(c.getPosition() + 1, rowsAvailable);
// Some file exports need to create the whole file in memory
// before saving it. (This is currently the case with
// the Excel export, whether we use jexcelapi or poi).
// On some devices, with large exports, we may not
// have enough memory to export the whole file.
// Here we detect a low memory situation, and stop
// creating rows.
long maxMemory = Runtime.getRuntime().maxMemory();
long allocatedMemory = Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory();
long pctFreeMemory = ((maxMemory - allocatedMemory) * 100) / maxMemory;
if (c.getPosition() % 100 == 0) {
Log.v(TAG, "pctFreeMemory:" + pctFreeMemory);
}
if (pctFreeMemory < THRESHOLD_LOW_MEMORY_PCT) {
Log.v(TAG, "Not enough memory to export the whole file");
if (listener != null) {
listener.onWarning(mContext.getString(R.string.export_warning_file_too_big_message));
}
break;
}
}
// Write the footer and clean up the file.
writeFooter();
if (listener != null) {
if (isCanceled()) {
listener.onComplete(mContext.getString(R.string.export_notif_canceled_content));
} else {
listener.onComplete(mContext.getString(R.string.export_save_to_external_storage_success, mFile.getAbsolutePath()));
}
}
return mFile;
} catch (IOException e) {
Log.e(TAG, "export Could not export file " + mFile + ": " + e.getMessage(), e);
} finally {
c.close();
}
}
if (listener != null) listener.onError(mContext.getString(R.string.export_notif_error_content));
return null;
}
}