Java tutorial
/* * Copyright (C) 2011 The Stanford MobiSocial Laboratory * * This file is part of Musubi, a mobile social network. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ package edu.stanford.mobisocial.dungbeetle.feed.objects; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.io.InputStream; import mobisocial.socialkit.Obj; import mobisocial.socialkit.SignedObj; import org.json.JSONException; import org.json.JSONObject; import org.mobisocial.corral.ContentCorral; import org.mobisocial.corral.CorralClient; import android.app.Activity; import android.content.ContentResolver; import android.content.Context; import android.content.Intent; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.Matrix; import android.net.Uri; import android.util.Log; import android.util.Pair; import android.view.ViewGroup; import android.widget.ImageView; import android.widget.LinearLayout; import edu.stanford.mobisocial.dungbeetle.ImageGalleryActivity; import edu.stanford.mobisocial.dungbeetle.feed.iface.Activator; import edu.stanford.mobisocial.dungbeetle.feed.iface.DbEntryHandler; import edu.stanford.mobisocial.dungbeetle.feed.iface.FeedRenderer; import edu.stanford.mobisocial.dungbeetle.feed.iface.OutgoingMessageHandler; import edu.stanford.mobisocial.dungbeetle.feed.iface.UnprocessedMessageHandler; import edu.stanford.mobisocial.dungbeetle.model.Contact; import edu.stanford.mobisocial.dungbeetle.model.DbObject; import edu.stanford.mobisocial.dungbeetle.model.Feed; import edu.stanford.mobisocial.dungbeetle.util.FastBase64; import edu.stanford.mobisocial.dungbeetle.util.PhotoTaker; public class PictureObj extends DbEntryHandler implements FeedRenderer, Activator, UnprocessedMessageHandler, OutgoingMessageHandler { public static final String TAG = "PictureObj"; public static final String TYPE = "picture"; public static final String DATA = "data"; // TODO: This is a hack, with many ways to fix. For example, // it can be used with its timestamp and an instance variable to // track a users' latest ip address. // Security should also be considered. @Override public String getType() { return TYPE; } /** * This does NOT do any SCALING! */ public static DbObject from(byte[] data) { return new DbObject(TYPE, new JSONObject(), data); } public static DbObject from(JSONObject base, byte[] data) { return new DbObject(TYPE, base, data); } @Override public Pair<JSONObject, byte[]> splitRaw(JSONObject json) { byte[] raw = FastBase64.decode(json.optString(DATA)); json.remove(DATA); return new Pair<JSONObject, byte[]>(json, raw); } public static DbObject from(Context context, Uri imageUri) throws IOException { // Query gallery for camera picture via // Android ContentResolver interface ContentResolver cr = context.getContentResolver(); BitmapFactory.Options options = new BitmapFactory.Options(); options.inJustDecodeBounds = true; BitmapFactory.decodeStream(cr.openInputStream(imageUri), null, options); int targetSize = 200; int xScale = (options.outWidth + targetSize - 1) / targetSize; int yScale = (options.outHeight + targetSize - 1) / targetSize; int scale = xScale < yScale ? xScale : yScale; //uncomment this to get faster power of two scaling //for(int i = 0; i < 32; ++i) { // int mushed = scale & ~(1 << i); // if(mushed != 0) // scale = mushed; //} options.inJustDecodeBounds = false; options.inSampleSize = scale; Bitmap sourceBitmap = BitmapFactory.decodeStream(cr.openInputStream(imageUri), null, options); int width = sourceBitmap.getWidth(); int height = sourceBitmap.getHeight(); int cropSize = Math.min(width, height); float scaleSize = ((float) targetSize) / cropSize; Matrix matrix = new Matrix(); matrix.postScale(scaleSize, scaleSize); float rotation = PhotoTaker.rotationForImage(context, imageUri); if (rotation != 0f) { matrix.preRotate(rotation); } Bitmap resizedBitmap = Bitmap.createBitmap(sourceBitmap, 0, 0, width, height, matrix, true); ByteArrayOutputStream baos = new ByteArrayOutputStream(); resizedBitmap.compress(Bitmap.CompressFormat.JPEG, 90, baos); byte[] data = baos.toByteArray(); sourceBitmap.recycle(); sourceBitmap = null; resizedBitmap.recycle(); resizedBitmap = null; System.gc(); // TODO: gross. JSONObject base = new JSONObject(); if (ContentCorral.CONTENT_CORRAL_ENABLED) { try { String type = cr.getType(imageUri); if (type == null) { type = "image/jpeg"; } base.put(CorralClient.OBJ_LOCAL_URI, imageUri.toString()); base.put(CorralClient.OBJ_MIME_TYPE, type); String localIp = ContentCorral.getLocalIpAddress(); if (localIp != null) { base.put(Contact.ATTR_LAN_IP, localIp); } } catch (JSONException e) { Log.e(TAG, "impossible json error possible!"); } } return from(base, data); } public void render(Context context, ViewGroup frame, Obj obj, boolean allowInteractions) { JSONObject content = obj.getJson(); byte[] raw = obj.getRaw(); if (raw == null) { Pair<JSONObject, byte[]> p = splitRaw(content); content = p.first; raw = p.second; } ImageView imageView = new ImageView(context); imageView.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT)); imageView.setImageBitmap(BitmapFactory.decodeByteArray(raw, 0, raw.length)); // App.instance().objectImages.lazyLoadImage(raw.hashCode(), raw, imageView); frame.addView(imageView); } public Pair<JSONObject, byte[]> handleUnprocessed(Context context, JSONObject msg) { if (!msg.has(DATA)) { return null; } byte[] bytes = FastBase64.decode(msg.optString(DATA)); msg.remove(DATA); return new Pair<JSONObject, byte[]>(msg, bytes); } @Override public void activate(Context context, SignedObj obj) { // TODO: set data uri for obj Intent intent = new Intent(context, ImageGalleryActivity.class); intent.setData(Feed.uriForName(obj.getFeedName())); intent.putExtra("objHash", obj.getHash()); if (!(context instanceof Activity)) { intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK); } context.startActivity(intent); } public JSONObject mergeRaw(JSONObject objData, byte[] raw) { try { if (raw != null) objData = objData.put(DATA, FastBase64.encodeToString(raw)); } catch (JSONException e) { e.printStackTrace(); } return objData; } @Override public void handleDirectMessage(Context context, Contact from, JSONObject msg) { } private static byte[] getBytesFromFile(InputStream is) { try { ByteArrayOutputStream buffer = new ByteArrayOutputStream(); int nRead; byte[] data = new byte[16384]; while ((nRead = is.read(data, 0, data.length)) != -1) { buffer.write(data, 0, nRead); } buffer.flush(); return buffer.toByteArray(); } catch (IOException e) { Log.e(TAG, "Error reading bytes from file", e); return null; } } @Override public Pair<JSONObject, byte[]> handleOutgoing(JSONObject json) { byte[] bytes = FastBase64.decode(json.optString(DATA)); json.remove(DATA); return new Pair<JSONObject, byte[]>(json, bytes); } }