Android example source code file (PduPersister.java)

This example Android source code file (PduPersister.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Android by Example" ^TM.

Java - Android tags/keywords

android, contentvalues, cursor, encodedstringvalue, entry, failed, google, hashmap, integer, io, ioexception, mms, mmsexception, pduheaders, pdupart, pdupersister, string, uri, util, utilities

The PduPersister.java Android example source code

/*
 * Copyright (C) 2007-2008 Esmertec AG.
 * Copyright (C) 2007-2008 The Android Open Source Project
 *
 * 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.google.android.mms.pdu;

import com.google.android.mms.ContentType;
import com.google.android.mms.InvalidHeaderValueException;
import com.google.android.mms.MmsException;
import com.google.android.mms.util.PduCache;
import com.google.android.mms.util.PduCacheEntry;
import com.google.android.mms.util.SqliteWrapper;

import android.content.ContentResolver;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.DatabaseUtils;
import android.net.Uri;
import android.provider.Telephony;
import android.provider.Telephony.Mms;
import android.provider.Telephony.MmsSms;
import android.provider.Telephony.Threads;
import android.provider.Telephony.Mms.Addr;
import android.provider.Telephony.Mms.Part;
import android.provider.Telephony.MmsSms.PendingMessages;
import android.text.TextUtils;
import android.util.Config;
import android.util.Log;

import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
import java.util.Map.Entry;

import com.google.android.mms.pdu.EncodedStringValue;

/**
 * This class is the high-level manager of PDU storage.
 */
public class PduPersister {
    private static final String TAG = "PduPersister";
    private static final boolean DEBUG = false;
    private static final boolean LOCAL_LOGV = DEBUG ? Config.LOGD : Config.LOGV;

    private static final long DUMMY_THREAD_ID = Long.MAX_VALUE;

    /**
     * The uri of temporary drm objects.
     */
    public static final String TEMPORARY_DRM_OBJECT_URI =
        "content://mms/" + Long.MAX_VALUE + "/part";
    /**
     * Indicate that we transiently failed to process a MM.
     */
    public static final int PROC_STATUS_TRANSIENT_FAILURE   = 1;
    /**
     * Indicate that we permanently failed to process a MM.
     */
    public static final int PROC_STATUS_PERMANENTLY_FAILURE = 2;
    /**
     * Indicate that we have successfully processed a MM.
     */
    public static final int PROC_STATUS_COMPLETED           = 3;

    private static PduPersister sPersister;
    private static final PduCache PDU_CACHE_INSTANCE;

    private static final int[] ADDRESS_FIELDS = new int[] {
            PduHeaders.BCC,
            PduHeaders.CC,
            PduHeaders.FROM,
            PduHeaders.TO
    };

    private static final String[] PDU_PROJECTION = new String[] {
        Mms._ID,
        Mms.MESSAGE_BOX,
        Mms.THREAD_ID,
        Mms.RETRIEVE_TEXT,
        Mms.SUBJECT,
        Mms.CONTENT_LOCATION,
        Mms.CONTENT_TYPE,
        Mms.MESSAGE_CLASS,
        Mms.MESSAGE_ID,
        Mms.RESPONSE_TEXT,
        Mms.TRANSACTION_ID,
        Mms.CONTENT_CLASS,
        Mms.DELIVERY_REPORT,
        Mms.MESSAGE_TYPE,
        Mms.MMS_VERSION,
        Mms.PRIORITY,
        Mms.READ_REPORT,
        Mms.READ_STATUS,
        Mms.REPORT_ALLOWED,
        Mms.RETRIEVE_STATUS,
        Mms.STATUS,
        Mms.DATE,
        Mms.DELIVERY_TIME,
        Mms.EXPIRY,
        Mms.MESSAGE_SIZE,
        Mms.SUBJECT_CHARSET,
        Mms.RETRIEVE_TEXT_CHARSET,
    };

    private static final int PDU_COLUMN_ID                    = 0;
    private static final int PDU_COLUMN_MESSAGE_BOX           = 1;
    private static final int PDU_COLUMN_THREAD_ID             = 2;
    private static final int PDU_COLUMN_RETRIEVE_TEXT         = 3;
    private static final int PDU_COLUMN_SUBJECT               = 4;
    private static final int PDU_COLUMN_CONTENT_LOCATION      = 5;
    private static final int PDU_COLUMN_CONTENT_TYPE          = 6;
    private static final int PDU_COLUMN_MESSAGE_CLASS         = 7;
    private static final int PDU_COLUMN_MESSAGE_ID            = 8;
    private static final int PDU_COLUMN_RESPONSE_TEXT         = 9;
    private static final int PDU_COLUMN_TRANSACTION_ID        = 10;
    private static final int PDU_COLUMN_CONTENT_CLASS         = 11;
    private static final int PDU_COLUMN_DELIVERY_REPORT       = 12;
    private static final int PDU_COLUMN_MESSAGE_TYPE          = 13;
    private static final int PDU_COLUMN_MMS_VERSION           = 14;
    private static final int PDU_COLUMN_PRIORITY              = 15;
    private static final int PDU_COLUMN_READ_REPORT           = 16;
    private static final int PDU_COLUMN_READ_STATUS           = 17;
    private static final int PDU_COLUMN_REPORT_ALLOWED        = 18;
    private static final int PDU_COLUMN_RETRIEVE_STATUS       = 19;
    private static final int PDU_COLUMN_STATUS                = 20;
    private static final int PDU_COLUMN_DATE                  = 21;
    private static final int PDU_COLUMN_DELIVERY_TIME         = 22;
    private static final int PDU_COLUMN_EXPIRY                = 23;
    private static final int PDU_COLUMN_MESSAGE_SIZE          = 24;
    private static final int PDU_COLUMN_SUBJECT_CHARSET       = 25;
    private static final int PDU_COLUMN_RETRIEVE_TEXT_CHARSET = 26;

    private static final String[] PART_PROJECTION = new String[] {
        Part._ID,
        Part.CHARSET,
        Part.CONTENT_DISPOSITION,
        Part.CONTENT_ID,
        Part.CONTENT_LOCATION,
        Part.CONTENT_TYPE,
        Part.FILENAME,
        Part.NAME,
        Part.TEXT
    };

    private static final int PART_COLUMN_ID                  = 0;
    private static final int PART_COLUMN_CHARSET             = 1;
    private static final int PART_COLUMN_CONTENT_DISPOSITION = 2;
    private static final int PART_COLUMN_CONTENT_ID          = 3;
    private static final int PART_COLUMN_CONTENT_LOCATION    = 4;
    private static final int PART_COLUMN_CONTENT_TYPE        = 5;
    private static final int PART_COLUMN_FILENAME            = 6;
    private static final int PART_COLUMN_NAME                = 7;
    private static final int PART_COLUMN_TEXT                = 8;

    private static final HashMap<Uri, Integer> MESSAGE_BOX_MAP;
    // These map are used for convenience in persist() and load().
    private static final HashMap<Integer, Integer> CHARSET_COLUMN_INDEX_MAP;
    private static final HashMap<Integer, Integer> ENCODED_STRING_COLUMN_INDEX_MAP;
    private static final HashMap<Integer, Integer> TEXT_STRING_COLUMN_INDEX_MAP;
    private static final HashMap<Integer, Integer> OCTET_COLUMN_INDEX_MAP;
    private static final HashMap<Integer, Integer> LONG_COLUMN_INDEX_MAP;
    private static final HashMap<Integer, String> CHARSET_COLUMN_NAME_MAP;
    private static final HashMap<Integer, String> ENCODED_STRING_COLUMN_NAME_MAP;
    private static final HashMap<Integer, String> TEXT_STRING_COLUMN_NAME_MAP;
    private static final HashMap<Integer, String> OCTET_COLUMN_NAME_MAP;
    private static final HashMap<Integer, String> LONG_COLUMN_NAME_MAP;

    static {
        MESSAGE_BOX_MAP = new HashMap<Uri, Integer>();
        MESSAGE_BOX_MAP.put(Mms.Inbox.CONTENT_URI,  Mms.MESSAGE_BOX_INBOX);
        MESSAGE_BOX_MAP.put(Mms.Sent.CONTENT_URI,   Mms.MESSAGE_BOX_SENT);
        MESSAGE_BOX_MAP.put(Mms.Draft.CONTENT_URI,  Mms.MESSAGE_BOX_DRAFTS);
        MESSAGE_BOX_MAP.put(Mms.Outbox.CONTENT_URI, Mms.MESSAGE_BOX_OUTBOX);

        CHARSET_COLUMN_INDEX_MAP = new HashMap<Integer, Integer>();
        CHARSET_COLUMN_INDEX_MAP.put(PduHeaders.SUBJECT, PDU_COLUMN_SUBJECT_CHARSET);
        CHARSET_COLUMN_INDEX_MAP.put(PduHeaders.RETRIEVE_TEXT, PDU_COLUMN_RETRIEVE_TEXT_CHARSET);

        CHARSET_COLUMN_NAME_MAP = new HashMap<Integer, String>();
        CHARSET_COLUMN_NAME_MAP.put(PduHeaders.SUBJECT, Mms.SUBJECT_CHARSET);
        CHARSET_COLUMN_NAME_MAP.put(PduHeaders.RETRIEVE_TEXT, Mms.RETRIEVE_TEXT_CHARSET);

        // Encoded string field code -> column index/name map.
        ENCODED_STRING_COLUMN_INDEX_MAP = new HashMap<Integer, Integer>();
        ENCODED_STRING_COLUMN_INDEX_MAP.put(PduHeaders.RETRIEVE_TEXT, PDU_COLUMN_RETRIEVE_TEXT);
        ENCODED_STRING_COLUMN_INDEX_MAP.put(PduHeaders.SUBJECT, PDU_COLUMN_SUBJECT);

        ENCODED_STRING_COLUMN_NAME_MAP = new HashMap<Integer, String>();
        ENCODED_STRING_COLUMN_NAME_MAP.put(PduHeaders.RETRIEVE_TEXT, Mms.RETRIEVE_TEXT);
        ENCODED_STRING_COLUMN_NAME_MAP.put(PduHeaders.SUBJECT, Mms.SUBJECT);

        // Text string field code -> column index/name map.
        TEXT_STRING_COLUMN_INDEX_MAP = new HashMap<Integer, Integer>();
        TEXT_STRING_COLUMN_INDEX_MAP.put(PduHeaders.CONTENT_LOCATION, PDU_COLUMN_CONTENT_LOCATION);
        TEXT_STRING_COLUMN_INDEX_MAP.put(PduHeaders.CONTENT_TYPE, PDU_COLUMN_CONTENT_TYPE);
        TEXT_STRING_COLUMN_INDEX_MAP.put(PduHeaders.MESSAGE_CLASS, PDU_COLUMN_MESSAGE_CLASS);
        TEXT_STRING_COLUMN_INDEX_MAP.put(PduHeaders.MESSAGE_ID, PDU_COLUMN_MESSAGE_ID);
        TEXT_STRING_COLUMN_INDEX_MAP.put(PduHeaders.RESPONSE_TEXT, PDU_COLUMN_RESPONSE_TEXT);
        TEXT_STRING_COLUMN_INDEX_MAP.put(PduHeaders.TRANSACTION_ID, PDU_COLUMN_TRANSACTION_ID);

        TEXT_STRING_COLUMN_NAME_MAP = new HashMap<Integer, String>();
        TEXT_STRING_COLUMN_NAME_MAP.put(PduHeaders.CONTENT_LOCATION, Mms.CONTENT_LOCATION);
        TEXT_STRING_COLUMN_NAME_MAP.put(PduHeaders.CONTENT_TYPE, Mms.CONTENT_TYPE);
        TEXT_STRING_COLUMN_NAME_MAP.put(PduHeaders.MESSAGE_CLASS, Mms.MESSAGE_CLASS);
        TEXT_STRING_COLUMN_NAME_MAP.put(PduHeaders.MESSAGE_ID, Mms.MESSAGE_ID);
        TEXT_STRING_COLUMN_NAME_MAP.put(PduHeaders.RESPONSE_TEXT, Mms.RESPONSE_TEXT);
        TEXT_STRING_COLUMN_NAME_MAP.put(PduHeaders.TRANSACTION_ID, Mms.TRANSACTION_ID);

        // Octet field code -> column index/name map.
        OCTET_COLUMN_INDEX_MAP = new HashMap<Integer, Integer>();
        OCTET_COLUMN_INDEX_MAP.put(PduHeaders.CONTENT_CLASS, PDU_COLUMN_CONTENT_CLASS);
        OCTET_COLUMN_INDEX_MAP.put(PduHeaders.DELIVERY_REPORT, PDU_COLUMN_DELIVERY_REPORT);
        OCTET_COLUMN_INDEX_MAP.put(PduHeaders.MESSAGE_TYPE, PDU_COLUMN_MESSAGE_TYPE);
        OCTET_COLUMN_INDEX_MAP.put(PduHeaders.MMS_VERSION, PDU_COLUMN_MMS_VERSION);
        OCTET_COLUMN_INDEX_MAP.put(PduHeaders.PRIORITY, PDU_COLUMN_PRIORITY);
        OCTET_COLUMN_INDEX_MAP.put(PduHeaders.READ_REPORT, PDU_COLUMN_READ_REPORT);
        OCTET_COLUMN_INDEX_MAP.put(PduHeaders.READ_STATUS, PDU_COLUMN_READ_STATUS);
        OCTET_COLUMN_INDEX_MAP.put(PduHeaders.REPORT_ALLOWED, PDU_COLUMN_REPORT_ALLOWED);
        OCTET_COLUMN_INDEX_MAP.put(PduHeaders.RETRIEVE_STATUS, PDU_COLUMN_RETRIEVE_STATUS);
        OCTET_COLUMN_INDEX_MAP.put(PduHeaders.STATUS, PDU_COLUMN_STATUS);

        OCTET_COLUMN_NAME_MAP = new HashMap<Integer, String>();
        OCTET_COLUMN_NAME_MAP.put(PduHeaders.CONTENT_CLASS, Mms.CONTENT_CLASS);
        OCTET_COLUMN_NAME_MAP.put(PduHeaders.DELIVERY_REPORT, Mms.DELIVERY_REPORT);
        OCTET_COLUMN_NAME_MAP.put(PduHeaders.MESSAGE_TYPE, Mms.MESSAGE_TYPE);
        OCTET_COLUMN_NAME_MAP.put(PduHeaders.MMS_VERSION, Mms.MMS_VERSION);
        OCTET_COLUMN_NAME_MAP.put(PduHeaders.PRIORITY, Mms.PRIORITY);
        OCTET_COLUMN_NAME_MAP.put(PduHeaders.READ_REPORT, Mms.READ_REPORT);
        OCTET_COLUMN_NAME_MAP.put(PduHeaders.READ_STATUS, Mms.READ_STATUS);
        OCTET_COLUMN_NAME_MAP.put(PduHeaders.REPORT_ALLOWED, Mms.REPORT_ALLOWED);
        OCTET_COLUMN_NAME_MAP.put(PduHeaders.RETRIEVE_STATUS, Mms.RETRIEVE_STATUS);
        OCTET_COLUMN_NAME_MAP.put(PduHeaders.STATUS, Mms.STATUS);

        // Long field code -> column index/name map.
        LONG_COLUMN_INDEX_MAP = new HashMap<Integer, Integer>();
        LONG_COLUMN_INDEX_MAP.put(PduHeaders.DATE, PDU_COLUMN_DATE);
        LONG_COLUMN_INDEX_MAP.put(PduHeaders.DELIVERY_TIME, PDU_COLUMN_DELIVERY_TIME);
        LONG_COLUMN_INDEX_MAP.put(PduHeaders.EXPIRY, PDU_COLUMN_EXPIRY);
        LONG_COLUMN_INDEX_MAP.put(PduHeaders.MESSAGE_SIZE, PDU_COLUMN_MESSAGE_SIZE);

        LONG_COLUMN_NAME_MAP = new HashMap<Integer, String>();
        LONG_COLUMN_NAME_MAP.put(PduHeaders.DATE, Mms.DATE);
        LONG_COLUMN_NAME_MAP.put(PduHeaders.DELIVERY_TIME, Mms.DELIVERY_TIME);
        LONG_COLUMN_NAME_MAP.put(PduHeaders.EXPIRY, Mms.EXPIRY);
        LONG_COLUMN_NAME_MAP.put(PduHeaders.MESSAGE_SIZE, Mms.MESSAGE_SIZE);

        PDU_CACHE_INSTANCE = PduCache.getInstance();
     }

    private final Context mContext;
    private final ContentResolver mContentResolver;

    private PduPersister(Context context) {
        mContext = context;
        mContentResolver = context.getContentResolver();
     }

    /** Get(or create if not exist) an instance of PduPersister */
    public static PduPersister getPduPersister(Context context) {
        if ((sPersister == null) || !context.equals(sPersister.mContext)) {
            sPersister = new PduPersister(context);
        }

        return sPersister;
    }

    private void setEncodedStringValueToHeaders(
            Cursor c, int columnIndex,
            PduHeaders headers, int mapColumn) {
        String s = c.getString(columnIndex);
        if ((s != null) && (s.length() > 0)) {
            int charsetColumnIndex = CHARSET_COLUMN_INDEX_MAP.get(mapColumn);
            int charset = c.getInt(charsetColumnIndex);
            EncodedStringValue value = new EncodedStringValue(
                    charset, getBytes(s));
            headers.setEncodedStringValue(value, mapColumn);
        }
    }

    private void setTextStringToHeaders(
            Cursor c, int columnIndex,
            PduHeaders headers, int mapColumn) {
        String s = c.getString(columnIndex);
        if (s != null) {
            headers.setTextString(getBytes(s), mapColumn);
        }
    }

    private void setOctetToHeaders(
            Cursor c, int columnIndex,
            PduHeaders headers, int mapColumn) throws InvalidHeaderValueException {
        if (!c.isNull(columnIndex)) {
            int b = c.getInt(columnIndex);
            headers.setOctet(b, mapColumn);
        }
    }

    private void setLongToHeaders(
            Cursor c, int columnIndex,
            PduHeaders headers, int mapColumn) {
        if (!c.isNull(columnIndex)) {
            long l = c.getLong(columnIndex);
            headers.setLongInteger(l, mapColumn);
        }
    }

    private Integer getIntegerFromPartColumn(Cursor c, int columnIndex) {
        if (!c.isNull(columnIndex)) {
            return c.getInt(columnIndex);
        }
        return null;
    }

    private byte[] getByteArrayFromPartColumn(Cursor c, int columnIndex) {
        if (!c.isNull(columnIndex)) {
            return getBytes(c.getString(columnIndex));
        }
        return null;
    }

    private PduPart[] loadParts(long msgId) throws MmsException {
        Cursor c = SqliteWrapper.query(mContext, mContentResolver,
                Uri.parse("content://mms/" + msgId + "/part"),
                PART_PROJECTION, null, null, null);

        PduPart[] parts = null;

        try {
            if ((c == null) || (c.getCount() == 0)) {
                if (LOCAL_LOGV) {
                    Log.v(TAG, "loadParts(" + msgId + "): no part to load.");
                }
                return null;
            }

            int partCount = c.getCount();
            int partIdx = 0;
            parts = new PduPart[partCount];
            while (c.moveToNext()) {
                PduPart part = new PduPart();
                Integer charset = getIntegerFromPartColumn(
                        c, PART_COLUMN_CHARSET);
                if (charset != null) {
                    part.setCharset(charset);
                }

                byte[] contentDisposition = getByteArrayFromPartColumn(
                        c, PART_COLUMN_CONTENT_DISPOSITION);
                if (contentDisposition != null) {
                    part.setContentDisposition(contentDisposition);
                }

                byte[] contentId = getByteArrayFromPartColumn(
                        c, PART_COLUMN_CONTENT_ID);
                if (contentId != null) {
                    part.setContentId(contentId);
                }

                byte[] contentLocation = getByteArrayFromPartColumn(
                        c, PART_COLUMN_CONTENT_LOCATION);
                if (contentLocation != null) {
                    part.setContentLocation(contentLocation);
                }

                byte[] contentType = getByteArrayFromPartColumn(
                        c, PART_COLUMN_CONTENT_TYPE);
                if (contentType != null) {
                    part.setContentType(contentType);
                } else {
                    throw new MmsException("Content-Type must be set.");
                }

                byte[] fileName = getByteArrayFromPartColumn(
                        c, PART_COLUMN_FILENAME);
                if (fileName != null) {
                    part.setFilename(fileName);
                }

                byte[] name = getByteArrayFromPartColumn(
                        c, PART_COLUMN_NAME);
                if (name != null) {
                    part.setName(name);
                }

                // Construct a Uri for this part.
                long partId = c.getLong(PART_COLUMN_ID);
                Uri partURI = Uri.parse("content://mms/part/" + partId);
                part.setDataUri(partURI);

                // For images/audio/video, we won't keep their data in Part
                // because their renderer accept Uri as source.
                String type = toIsoString(contentType);
                if (!ContentType.isImageType(type)
                        && !ContentType.isAudioType(type)
                        && !ContentType.isVideoType(type)) {
                    ByteArrayOutputStream baos = new ByteArrayOutputStream();
                    InputStream is = null;

                    // Store simple string values directly in the database instead of an
                    // external file.  This makes the text searchable and retrieval slightly
                    // faster.
                    if ("text/plain".equals(type) || "application/smil".equals(type)) {
                        String text = c.getString(PART_COLUMN_TEXT);
                        byte [] blob = new EncodedStringValue(text != null ? text : "")
                            .getTextString();
                        baos.write(blob, 0, blob.length);
                    } else {

                        try {
                            is = mContentResolver.openInputStream(partURI);

                            byte[] buffer = new byte[256];
                            int len = is.read(buffer);
                            while (len >= 0) {
                                baos.write(buffer, 0, len);
                                len = is.read(buffer);
                            }
                        } catch (IOException e) {
                            Log.e(TAG, "Failed to load part data", e);
                            c.close();
                            throw new MmsException(e);
                        } finally {
                            if (is != null) {
                                try {
                                    is.close();
                                } catch (IOException e) {
                                    Log.e(TAG, "Failed to close stream", e);
                                } // Ignore
                            }
                        }
                    }
                    part.setData(baos.toByteArray());
                }
                parts[partIdx++] = part;
            }
        } finally {
            if (c != null) {
                c.close();
            }
        }

        return parts;
    }

    private void loadAddress(long msgId, PduHeaders headers) {
        Cursor c = SqliteWrapper.query(mContext, mContentResolver,
                Uri.parse("content://mms/" + msgId + "/addr"),
                new String[] { Addr.ADDRESS, Addr.CHARSET, Addr.TYPE },
                null, null, null);

        if (c != null) {
            try {
                while (c.moveToNext()) {
                    String addr = c.getString(0);
                    if (!TextUtils.isEmpty(addr)) {
                        int addrType = c.getInt(2);
                        switch (addrType) {
                            case PduHeaders.FROM:
                                headers.setEncodedStringValue(
                                        new EncodedStringValue(c.getInt(1), getBytes(addr)),
                                        addrType);
                                break;
                            case PduHeaders.TO:
                            case PduHeaders.CC:
                            case PduHeaders.BCC:
                                headers.appendEncodedStringValue(
                                        new EncodedStringValue(c.getInt(1), getBytes(addr)),
                                        addrType);
                                break;
                            default:
                                Log.e(TAG, "Unknown address type: " + addrType);
                                break;
                        }
                    }
                }
            } finally {
                c.close();
            }
        }
    }

    /**
     * Load a PDU from storage by given Uri.
     *
     * @param uri The Uri of the PDU to be loaded.
     * @return A generic PDU object, it may be cast to dedicated PDU.
     * @throws MmsException Failed to load some fields of a PDU.
     */
    public GenericPdu load(Uri uri) throws MmsException {
        PduCacheEntry cacheEntry = PDU_CACHE_INSTANCE.get(uri);
        if (cacheEntry != null) {
            return cacheEntry.getPdu();
        }

        Cursor c = SqliteWrapper.query(mContext, mContentResolver, uri,
                        PDU_PROJECTION, null, null, null);
        PduHeaders headers = new PduHeaders();
        Set<Entry set;
        long msgId = ContentUris.parseId(uri);
        int msgBox;
        long threadId;

        try {
            if ((c == null) || (c.getCount() != 1) || !c.moveToFirst()) {
                throw new MmsException("Bad uri: " + uri);
            }

            msgBox = c.getInt(PDU_COLUMN_MESSAGE_BOX);
            threadId = c.getLong(PDU_COLUMN_THREAD_ID);

            set = ENCODED_STRING_COLUMN_INDEX_MAP.entrySet();
            for (Entry<Integer, Integer> e : set) {
                setEncodedStringValueToHeaders(
                        c, e.getValue(), headers, e.getKey());
            }

            set = TEXT_STRING_COLUMN_INDEX_MAP.entrySet();
            for (Entry<Integer, Integer> e : set) {
                setTextStringToHeaders(
                        c, e.getValue(), headers, e.getKey());
            }

            set = OCTET_COLUMN_INDEX_MAP.entrySet();
            for (Entry<Integer, Integer> e : set) {
                setOctetToHeaders(
                        c, e.getValue(), headers, e.getKey());
            }

            set = LONG_COLUMN_INDEX_MAP.entrySet();
            for (Entry<Integer, Integer> e : set) {
                setLongToHeaders(
                        c, e.getValue(), headers, e.getKey());
            }
        } finally {
            if (c != null) {
                c.close();
            }
        }

        // Check whether 'msgId' has been assigned a valid value.
        if (msgId == -1L) {
            throw new MmsException("Error! ID of the message: -1.");
        }

        // Load address information of the MM.
        loadAddress(msgId, headers);

        int msgType = headers.getOctet(PduHeaders.MESSAGE_TYPE);
        PduBody body = new PduBody();

        // For PDU which type is M_retrieve.conf or Send.req, we should
        // load multiparts and put them into the body of the PDU.
        if ((msgType == PduHeaders.MESSAGE_TYPE_RETRIEVE_CONF)
                || (msgType == PduHeaders.MESSAGE_TYPE_SEND_REQ)) {
            PduPart[] parts = loadParts(msgId);
            if (parts != null) {
                int partsNum = parts.length;
                for (int i = 0; i < partsNum; i++) {
                    body.addPart(parts[i]);
                }
            }
        }

        GenericPdu pdu = null;
        switch (msgType) {
            case PduHeaders.MESSAGE_TYPE_NOTIFICATION_IND:
                pdu = new NotificationInd(headers);
                break;
            case PduHeaders.MESSAGE_TYPE_DELIVERY_IND:
                pdu = new DeliveryInd(headers);
                break;
            case PduHeaders.MESSAGE_TYPE_READ_ORIG_IND:
                pdu = new ReadOrigInd(headers);
                break;
            case PduHeaders.MESSAGE_TYPE_RETRIEVE_CONF:
                pdu = new RetrieveConf(headers, body);
                break;
            case PduHeaders.MESSAGE_TYPE_SEND_REQ:
                pdu = new SendReq(headers, body);
                break;
            case PduHeaders.MESSAGE_TYPE_ACKNOWLEDGE_IND:
                pdu = new AcknowledgeInd(headers);
                break;
            case PduHeaders.MESSAGE_TYPE_NOTIFYRESP_IND:
                pdu = new NotifyRespInd(headers);
                break;
            case PduHeaders.MESSAGE_TYPE_READ_REC_IND:
                pdu = new ReadRecInd(headers);
                break;
            case PduHeaders.MESSAGE_TYPE_SEND_CONF:
            case PduHeaders.MESSAGE_TYPE_FORWARD_REQ:
            case PduHeaders.MESSAGE_TYPE_FORWARD_CONF:
            case PduHeaders.MESSAGE_TYPE_MBOX_STORE_REQ:
            case PduHeaders.MESSAGE_TYPE_MBOX_STORE_CONF:
            case PduHeaders.MESSAGE_TYPE_MBOX_VIEW_REQ:
            case PduHeaders.MESSAGE_TYPE_MBOX_VIEW_CONF:
            case PduHeaders.MESSAGE_TYPE_MBOX_UPLOAD_REQ:
            case PduHeaders.MESSAGE_TYPE_MBOX_UPLOAD_CONF:
            case PduHeaders.MESSAGE_TYPE_MBOX_DELETE_REQ:
            case PduHeaders.MESSAGE_TYPE_MBOX_DELETE_CONF:
            case PduHeaders.MESSAGE_TYPE_MBOX_DESCR:
            case PduHeaders.MESSAGE_TYPE_DELETE_REQ:
            case PduHeaders.MESSAGE_TYPE_DELETE_CONF:
            case PduHeaders.MESSAGE_TYPE_CANCEL_REQ:
            case PduHeaders.MESSAGE_TYPE_CANCEL_CONF:
                throw new MmsException(
                        "Unsupported PDU type: " + Integer.toHexString(msgType));

            default:
                throw new MmsException(
                        "Unrecognized PDU type: " + Integer.toHexString(msgType));
        }

        cacheEntry = new PduCacheEntry(pdu, msgBox, threadId);
        PDU_CACHE_INSTANCE.put(uri, cacheEntry);
        return pdu;
    }

    private void persistAddress(
            long msgId, int type, EncodedStringValue[] array) {
        ContentValues values = new ContentValues(3);

        for (EncodedStringValue addr : array) {
            values.clear(); // Clear all values first.
            values.put(Addr.ADDRESS, toIsoString(addr.getTextString()));
            values.put(Addr.CHARSET, addr.getCharacterSet());
            values.put(Addr.TYPE, type);

            Uri uri = Uri.parse("content://mms/" + msgId + "/addr");
            SqliteWrapper.insert(mContext, mContentResolver, uri, values);
        }
    }

    public Uri persistPart(PduPart part, long msgId)
            throws MmsException {
        Uri uri = Uri.parse("content://mms/" + msgId + "/part");
        ContentValues values = new ContentValues(8);

        int charset = part.getCharset();
        if (charset != 0 ) {
            values.put(Part.CHARSET, charset);
        }

        String contentType = null;
        if (part.getContentType() != null) {
            contentType = toIsoString(part.getContentType());
            values.put(Part.CONTENT_TYPE, contentType);
            // To ensure the SMIL part is always the first part.
            if (ContentType.APP_SMIL.equals(contentType)) {
                values.put(Part.SEQ, -1);
            }
        } else {
            throw new MmsException("MIME type of the part must be set.");
        }

        if (part.getFilename() != null) {
            String fileName = new String(part.getFilename());
            values.put(Part.FILENAME, fileName);
        }

        if (part.getName() != null) {
            String name = new String(part.getName());
            values.put(Part.NAME, name);
        }

        Object value = null;
        if (part.getContentDisposition() != null) {
            value = toIsoString(part.getContentDisposition());
            values.put(Part.CONTENT_DISPOSITION, (String) value);
        }

        if (part.getContentId() != null) {
            value = toIsoString(part.getContentId());
            values.put(Part.CONTENT_ID, (String) value);
        }

        if (part.getContentLocation() != null) {
            value = toIsoString(part.getContentLocation());
            values.put(Part.CONTENT_LOCATION, (String) value);
        }

        Uri res = SqliteWrapper.insert(mContext, mContentResolver, uri, values);
        if (res == null) {
            throw new MmsException("Failed to persist part, return null.");
        }

        persistData(part, res, contentType);
        // After successfully store the data, we should update
        // the dataUri of the part.
        part.setDataUri(res);

        return res;
    }

    /**
     * Save data of the part into storage. The source data may be given
     * by a byte[] or a Uri. If it's a byte[], directly save it
     * into storage, otherwise load source data from the dataUri and then
     * save it. If the data is an image, we may scale down it according
     * to user preference.
     *
     * @param part The PDU part which contains data to be saved.
     * @param uri The URI of the part.
     * @param contentType The MIME type of the part.
     * @throws MmsException Cannot find source data or error occurred
     *         while saving the data.
     */
    private void persistData(PduPart part, Uri uri,
            String contentType)
            throws MmsException {
        OutputStream os = null;
        InputStream is = null;

        try {
            byte[] data = part.getData();
            if ("text/plain".equals(contentType) || "application/smil".equals(contentType)) {
                ContentValues cv = new ContentValues();
                cv.put(Telephony.Mms.Part.TEXT, new EncodedStringValue(data).getString());
                if (mContentResolver.update(uri, cv, null, null) != 1) {
                    throw new MmsException("unable to update " + uri.toString());
                }
            } else {
                os = mContentResolver.openOutputStream(uri);
                if (data == null) {
                    Uri dataUri = part.getDataUri();
                    if ((dataUri == null) || (dataUri == uri)) {
                        Log.w(TAG, "Can't find data for this part.");
                        return;
                    }
                    is = mContentResolver.openInputStream(dataUri);

                    if (LOCAL_LOGV) {
                        Log.v(TAG, "Saving data to: " + uri);
                    }

                    byte[] buffer = new byte[256];
                    for (int len = 0; (len = is.read(buffer)) != -1; ) {
                        os.write(buffer, 0, len);
                    }
                } else {
                    if (LOCAL_LOGV) {
                        Log.v(TAG, "Saving data to: " + uri);
                    }
                    os.write(data);
                }
            }
        } catch (FileNotFoundException e) {
            Log.e(TAG, "Failed to open Input/Output stream.", e);
            throw new MmsException(e);
        } catch (IOException e) {
            Log.e(TAG, "Failed to read/write data.", e);
            throw new MmsException(e);
        } finally {
            if (os != null) {
                try {
                    os.close();
                } catch (IOException e) {
                    Log.e(TAG, "IOException while closing: " + os, e);
                } // Ignore
            }
            if (is != null) {
                try {
                    is.close();
                } catch (IOException e) {
                    Log.e(TAG, "IOException while closing: " + is, e);
                } // Ignore
            }
        }
    }

    private void updateAddress(
            long msgId, int type, EncodedStringValue[] array) {
        // Delete old address information and then insert new ones.
        SqliteWrapper.delete(mContext, mContentResolver,
                Uri.parse("content://mms/" + msgId + "/addr"),
                Addr.TYPE + "=" + type, null);

        persistAddress(msgId, type, array);
    }

    /**
     * Update headers of a SendReq.
     *
     * @param uri The PDU which need to be updated.
     * @param pdu New headers.
     * @throws MmsException Bad URI or updating failed.
     */
    public void updateHeaders(Uri uri, SendReq sendReq) {
        PDU_CACHE_INSTANCE.purge(uri);

        ContentValues values = new ContentValues(10);
        byte[] contentType = sendReq.getContentType();
        if (contentType != null) {
            values.put(Mms.CONTENT_TYPE, toIsoString(contentType));
        }

        long date = sendReq.getDate();
        if (date != -1) {
            values.put(Mms.DATE, date);
        }

        int deliveryReport = sendReq.getDeliveryReport();
        if (deliveryReport != 0) {
            values.put(Mms.DELIVERY_REPORT, deliveryReport);
        }

        long expiry = sendReq.getExpiry();
        if (expiry != -1) {
            values.put(Mms.EXPIRY, expiry);
        }

        byte[] msgClass = sendReq.getMessageClass();
        if (msgClass != null) {
            values.put(Mms.MESSAGE_CLASS, toIsoString(msgClass));
        }

        int priority = sendReq.getPriority();
        if (priority != 0) {
            values.put(Mms.PRIORITY, priority);
        }

        int readReport = sendReq.getReadReport();
        if (readReport != 0) {
            values.put(Mms.READ_REPORT, readReport);
        }

        byte[] transId = sendReq.getTransactionId();
        if (transId != null) {
            values.put(Mms.TRANSACTION_ID, toIsoString(transId));
        }

        EncodedStringValue subject = sendReq.getSubject();
        if (subject != null) {
            values.put(Mms.SUBJECT, toIsoString(subject.getTextString()));
            values.put(Mms.SUBJECT_CHARSET, subject.getCharacterSet());
        } else {
            values.put(Mms.SUBJECT, "");
        }

        long messageSize = sendReq.getMessageSize();
        if (messageSize > 0) {
            values.put(Mms.MESSAGE_SIZE, messageSize);
        }

        PduHeaders headers = sendReq.getPduHeaders();
        HashSet<String> recipients = new HashSet();
        for (int addrType : ADDRESS_FIELDS) {
            EncodedStringValue[] array = null;
            if (addrType == PduHeaders.FROM) {
                EncodedStringValue v = headers.getEncodedStringValue(addrType);
                if (v != null) {
                    array = new EncodedStringValue[1];
                    array[0] = v;
                }
            } else {
                array = headers.getEncodedStringValues(addrType);
            }

            if (array != null) {
                long msgId = ContentUris.parseId(uri);
                updateAddress(msgId, addrType, array);
                if (addrType == PduHeaders.TO) {
                    for (EncodedStringValue v : array) {
                        if (v != null) {
                            recipients.add(v.getString());
                        }
                    }
                }
            }
        }

        long threadId = Threads.getOrCreateThreadId(mContext, recipients);
        values.put(Mms.THREAD_ID, threadId);

        SqliteWrapper.update(mContext, mContentResolver, uri, values, null, null);
    }

    private void updatePart(Uri uri, PduPart part) throws MmsException {
        ContentValues values = new ContentValues(7);

        int charset = part.getCharset();
        if (charset != 0 ) {
            values.put(Part.CHARSET, charset);
        }

        String contentType = null;
        if (part.getContentType() != null) {
            contentType = toIsoString(part.getContentType());
            values.put(Part.CONTENT_TYPE, contentType);
        } else {
            throw new MmsException("MIME type of the part must be set.");
        }

        if (part.getFilename() != null) {
            String fileName = new String(part.getFilename());
            values.put(Part.FILENAME, fileName);
        }

        if (part.getName() != null) {
            String name = new String(part.getName());
            values.put(Part.NAME, name);
        }

        Object value = null;
        if (part.getContentDisposition() != null) {
            value = toIsoString(part.getContentDisposition());
            values.put(Part.CONTENT_DISPOSITION, (String) value);
        }

        if (part.getContentId() != null) {
            value = toIsoString(part.getContentId());
            values.put(Part.CONTENT_ID, (String) value);
        }

        if (part.getContentLocation() != null) {
            value = toIsoString(part.getContentLocation());
            values.put(Part.CONTENT_LOCATION, (String) value);
        }

        SqliteWrapper.update(mContext, mContentResolver, uri, values, null, null);

        // Only update the data when:
        // 1. New binary data supplied or
        // 2. The Uri of the part is different from the current one.
        if ((part.getData() != null)
                || (uri != part.getDataUri())) {
            persistData(part, uri, contentType);
        }
    }

    /**
     * Update all parts of a PDU.
     *
     * @param uri The PDU which need to be updated.
     * @param body New message body of the PDU.
     * @throws MmsException Bad URI or updating failed.
     */
    public void updateParts(Uri uri, PduBody body)
            throws MmsException {
        PduCacheEntry cacheEntry = PDU_CACHE_INSTANCE.get(uri);
        if (cacheEntry != null) {
            ((MultimediaMessagePdu) cacheEntry.getPdu()).setBody(body);
        }

        ArrayList<PduPart> toBeCreated = new ArrayList();
        HashMap<Uri, PduPart> toBeUpdated = new HashMap();

        int partsNum = body.getPartsNum();
        StringBuilder filter = new StringBuilder().append('(');
        for (int i = 0; i < partsNum; i++) {
            PduPart part = body.getPart(i);
            Uri partUri = part.getDataUri();
            if ((partUri == null) || !partUri.getAuthority().startsWith("mms")) {
                toBeCreated.add(part);
            } else {
                toBeUpdated.put(partUri, part);

                // Don't use 'i > 0' to determine whether we should append
                // 'AND' since 'i = 0' may be skipped in another branch.
                if (filter.length() > 1) {
                    filter.append(" AND ");
                }

                filter.append(Part._ID);
                filter.append("!=");
                DatabaseUtils.appendEscapedSQLString(filter, partUri.getLastPathSegment());
            }
        }
        filter.append(')');

        long msgId = ContentUris.parseId(uri);

        // Remove the parts which doesn't exist anymore.
        SqliteWrapper.delete(mContext, mContentResolver,
                Uri.parse(Mms.CONTENT_URI + "/" + msgId + "/part"),
                filter.length() > 2 ? filter.toString() : null, null);

        // Create new parts which didn't exist before.
        for (PduPart part : toBeCreated) {
            persistPart(part, msgId);
        }

        // Update the modified parts.
        for (Map.Entry<Uri, PduPart> e : toBeUpdated.entrySet()) {
            updatePart(e.getKey(), e.getValue());
        }
    }

    /**
     * Persist a PDU object to specific location in the storage.
     *
     * @param pdu The PDU object to be stored.
     * @param uri Where to store the given PDU object.
     * @return A Uri which can be used to access the stored PDU.
     */
    public Uri persist(GenericPdu pdu, Uri uri) throws MmsException {
        if (uri == null) {
            throw new MmsException("Uri may not be null.");
        }

        Integer msgBox = MESSAGE_BOX_MAP.get(uri);
        if (msgBox == null) {
            throw new MmsException(
                    "Bad destination, must be one of "
                    + "content://mms/inbox, content://mms/sent, "
                    + "content://mms/drafts, content://mms/outbox, "
                    + "content://mms/temp.");
        }
        PDU_CACHE_INSTANCE.purge(uri);

        PduHeaders header = pdu.getPduHeaders();
        PduBody body = null;
        ContentValues values = new ContentValues();
        Set<Entry set;

        set = ENCODED_STRING_COLUMN_NAME_MAP.entrySet();
        for (Entry<Integer, String> e : set) {
            int field = e.getKey();
            EncodedStringValue encodedString = header.getEncodedStringValue(field);
            if (encodedString != null) {
                String charsetColumn = CHARSET_COLUMN_NAME_MAP.get(field);
                values.put(e.getValue(), toIsoString(encodedString.getTextString()));
                values.put(charsetColumn, encodedString.getCharacterSet());
            }
        }

        set = TEXT_STRING_COLUMN_NAME_MAP.entrySet();
        for (Entry<Integer, String> e : set){
            byte[] text = header.getTextString(e.getKey());
            if (text != null) {
                values.put(e.getValue(), toIsoString(text));
            }
        }

        set = OCTET_COLUMN_NAME_MAP.entrySet();
        for (Entry<Integer, String> e : set){
            int b = header.getOctet(e.getKey());
            if (b != 0) {
                values.put(e.getValue(), b);
            }
        }

        set = LONG_COLUMN_NAME_MAP.entrySet();
        for (Entry<Integer, String> e : set){
            long l = header.getLongInteger(e.getKey());
            if (l != -1L) {
                values.put(e.getValue(), l);
            }
        }

        HashMap<Integer, EncodedStringValue[]> addressMap =
                new HashMap<Integer, EncodedStringValue[]>(ADDRESS_FIELDS.length);
        // Save address information.
        for (int addrType : ADDRESS_FIELDS) {
            EncodedStringValue[] array = null;
            if (addrType == PduHeaders.FROM) {
                EncodedStringValue v = header.getEncodedStringValue(addrType);
                if (v != null) {
                    array = new EncodedStringValue[1];
                    array[0] = v;
                }
            } else {
                array = header.getEncodedStringValues(addrType);
            }
            addressMap.put(addrType, array);
        }

        HashSet<String> recipients = new HashSet();
        long threadId = DUMMY_THREAD_ID;
        int msgType = pdu.getMessageType();
        // Here we only allocate thread ID for M-Notification.ind,
        // M-Retrieve.conf and M-Send.req.
        // Some of other PDU types may be allocated a thread ID outside
        // this scope.
        if ((msgType == PduHeaders.MESSAGE_TYPE_NOTIFICATION_IND)
                || (msgType == PduHeaders.MESSAGE_TYPE_RETRIEVE_CONF)
                || (msgType == PduHeaders.MESSAGE_TYPE_SEND_REQ)) {
            EncodedStringValue[] array = null;
            switch (msgType) {
                case PduHeaders.MESSAGE_TYPE_NOTIFICATION_IND:
                case PduHeaders.MESSAGE_TYPE_RETRIEVE_CONF:
                    array = addressMap.get(PduHeaders.FROM);
                    break;
                case PduHeaders.MESSAGE_TYPE_SEND_REQ:
                    array = addressMap.get(PduHeaders.TO);
                    break;
            }

            if (array != null) {
                for (EncodedStringValue v : array) {
                    if (v != null) {
                        recipients.add(v.getString());
                    }
                }
            }
            threadId = Threads.getOrCreateThreadId(mContext, recipients);
        }
        values.put(Mms.THREAD_ID, threadId);

        // Save parts first to avoid inconsistent message is loaded
        // while saving the parts.
        long dummyId = System.currentTimeMillis(); // Dummy ID of the msg.
        // Get body if the PDU is a RetrieveConf or SendReq.
        if (pdu instanceof MultimediaMessagePdu) {
            body = ((MultimediaMessagePdu) pdu).getBody();
            // Start saving parts if necessary.
            if (body != null) {
                int partsNum = body.getPartsNum();
                for (int i = 0; i < partsNum; i++) {
                    PduPart part = body.getPart(i);
                    persistPart(part, dummyId);
                }
            }
        }

        Uri res = SqliteWrapper.insert(mContext, mContentResolver, uri, values);
        if (res == null) {
            throw new MmsException("persist() failed: return null.");
        }

        // Get the real ID of the PDU and update all parts which were
        // saved with the dummy ID.
        long msgId = ContentUris.parseId(res);
        values = new ContentValues(1);
        values.put(Part.MSG_ID, msgId);
        SqliteWrapper.update(mContext, mContentResolver,
                             Uri.parse("content://mms/" + dummyId + "/part"),
                             values, null, null);
        // We should return the longest URI of the persisted PDU, for
        // example, if input URI is "content://mms/inbox" and the _ID of
        // persisted PDU is '8', we should return "content://mms/inbox/8"
        // instead of "content://mms/8".
        // FIXME: Should the MmsProvider be responsible for this???
        res = Uri.parse(uri + "/" + msgId);

        // Save address information.
        for (int addrType : ADDRESS_FIELDS) {
            EncodedStringValue[] array = addressMap.get(addrType);
            if (array != null) {
                persistAddress(msgId, addrType, array);
            }
        }

        return res;
    }

    /**
     * Move a PDU object from one location to another.
     *
     * @param from Specify the PDU object to be moved.
     * @param to The destination location, should be one of the following:
     *        "content://mms/inbox", "content://mms/sent",
     *        "content://mms/drafts", "content://mms/outbox",
     *        "content://mms/trash".
     * @return New Uri of the moved PDU.
     * @throws MmsException Error occurred while moving the message.
     */
    public Uri move(Uri from, Uri to) throws MmsException {
        // Check whether the 'msgId' has been assigned a valid value.
        long msgId = ContentUris.parseId(from);
        if (msgId == -1L) {
            throw new MmsException("Error! ID of the message: -1.");
        }

        // Get corresponding int value of destination box.
        Integer msgBox = MESSAGE_BOX_MAP.get(to);
        if (msgBox == null) {
            throw new MmsException(
                    "Bad destination, must be one of "
                    + "content://mms/inbox, content://mms/sent, "
                    + "content://mms/drafts, content://mms/outbox, "
                    + "content://mms/temp.");
        }

        ContentValues values = new ContentValues(1);
        values.put(Mms.MESSAGE_BOX, msgBox);
        SqliteWrapper.update(mContext, mContentResolver, from, values, null, null);
        return ContentUris.withAppendedId(to, msgId);
    }

    /**
     * Wrap a byte[] into a String.
     */
    public static String toIsoString(byte[] bytes) {
        try {
            return new String(bytes, CharacterSets.MIMENAME_ISO_8859_1);
        } catch (UnsupportedEncodingException e) {
            // Impossible to reach here!
            Log.e(TAG, "ISO_8859_1 must be supported!", e);
            return "";
        }
    }

    /**
     * Unpack a given String into a byte[].
     */
    public static byte[] getBytes(String data) {
        try {
            return data.getBytes(CharacterSets.MIMENAME_ISO_8859_1);
        } catch (UnsupportedEncodingException e) {
            // Impossible to reach here!
            Log.e(TAG, "ISO_8859_1 must be supported!", e);
            return new byte[0];
        }
    }

    /**
     * Remove all objects in the temporary path.
     */
    public void release() {
        Uri uri = Uri.parse(TEMPORARY_DRM_OBJECT_URI);
        SqliteWrapper.delete(mContext, mContentResolver, uri, null, null);
    }

    /**
     * Find all messages to be sent or downloaded before certain time.
     */
    public Cursor getPendingMessages(long dueTime) {
        Uri.Builder uriBuilder = PendingMessages.CONTENT_URI.buildUpon();
        uriBuilder.appendQueryParameter("protocol", "mms");

        String selection = PendingMessages.ERROR_TYPE + " < ?"
                + " AND " + PendingMessages.DUE_TIME + " <= ?";

        String[] selectionArgs = new String[] {
                String.valueOf(MmsSms.ERR_TYPE_GENERIC_PERMANENT),
                String.valueOf(dueTime)
        };

        return SqliteWrapper.query(mContext, mContentResolver,
                uriBuilder.build(), null, selection, selectionArgs,
                PendingMessages.DUE_TIME);
    }
}