com.asksven.commandcenter.valueobjects.CommandReaderWriter.java Source code

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Here is the source code for com.asksven.commandcenter.valueobjects.CommandReaderWriter.java

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/*
 * Copyright (C) 2011 asksven
 *
 * 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 com.asksven.commandcenter.valueobjects;

/**
 * @author sven
 *
 */

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.Writer;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.HttpStatus;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

import android.content.Context;
import android.content.SharedPreferences;
import android.os.Environment;
import android.preference.PreferenceManager;
import android.util.Log;

import com.asksven.commandcenter.exec.DataStorage;
import com.google.gson.Gson;

public class CommandReaderWriter {

    private static final String TAG = "CommandReader";

    public static CommandCollection readUrl(String strUrl) {
        CommandCollection data = null;

        try {
            InputStream source = retrieveStream(strUrl);

            readStream(source);

        } catch (Exception e) {
            e.printStackTrace();
        }

        return data;
    }

    public static CommandCollection readFile(Context ctx, String strFileName) {
        CommandCollection data = new CommandCollection();

        try {
            FileInputStream source = new FileInputStream(
                    DataStorage.getExternalStoragePath(ctx) + "/" + strFileName);

            data = readStream(source);

            source.close();

        } catch (Exception e) {
            e.printStackTrace();
            // make sure the returned data is consistent
            data.setEntries(new ArrayList<Command>());
        }

        return data;
    }

    public static void writeFile(Context ctx, CommandCollection data, String strFileName) {
        try {

            FileOutputStream target = new FileOutputStream(
                    DataStorage.getExternalStoragePath(ctx) + "/" + strFileName);

            writeStream(data, target);

            target.close();

        } catch (FileNotFoundException e) {
            Log.e(TAG, "File could not be written: " + e.getMessage());
            e.printStackTrace();
        } catch (IOException e) {
            Log.e(TAG, "File could not be closed: " + e.getMessage());
            e.printStackTrace();
        }

    }

    public static CommandCollection readStream(InputStream source) throws Exception {
        CommandCollection data = null;

        if (source == null) {
            return null;
        }
        Gson gson = new Gson();

        Reader reader = new InputStreamReader(source);

        // Now do the magic.
        data = gson.fromJson(reader, CommandCollection.class);

        reader.close();

        return data;
    }

    public static void writeStream(CommandCollection data, OutputStream target) // throws Exception
    {

        if (target == null) {
            return;
        }
        Gson gson = new Gson();

        try {
            Writer writer = new OutputStreamWriter(target);

            // Now do the magic.
            gson.toJson(data, CommandCollection.class, writer);
            writer.close();
        } catch (Exception e) {
            Log.e(TAG, "Error while marshalling json file: " + e.getMessage());
        }
    }

    private static InputStream retrieveStream(String url) {
        DefaultHttpClient client = new DefaultHttpClient();
        HttpGet getRequest = new HttpGet(url);
        try {
            HttpResponse getResponse = client.execute(getRequest);

            final int statusCode = getResponse.getStatusLine().getStatusCode();

            if (statusCode != HttpStatus.SC_OK) {
                Log.w(TAG, "Error " + statusCode + " for URL " + url);
                return null;
            }
            HttpEntity getResponseEntity = getResponse.getEntity();
            return getResponseEntity.getContent();
        } catch (IOException e) {
            getRequest.abort();
            Log.w(TAG, "Error for URL " + url, e);
        }
        return null;
    }

}