| /* |
| * Copyright (C) 2010 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 android.nfc; |
| |
| import android.os.Parcel; |
| import android.os.Parcelable; |
| |
| /** |
| * Represents an NDEF (NFC Data Exchange Format) data message that contains one or more {@link |
| * NdefRecord}s. |
| * <p>An NDEF message includes "records" that can contain different sets of data, such as |
| * MIME-type media, a URI, or one of the supported RTD types (see {@link NdefRecord}). An NDEF |
| * message always contains zero or more NDEF records.</p> |
| * <p>This is an immutable data class. |
| */ |
| public final class NdefMessage implements Parcelable { |
| private static final byte FLAG_MB = (byte) 0x80; |
| private static final byte FLAG_ME = (byte) 0x40; |
| |
| private final NdefRecord[] mRecords; |
| |
| /** |
| * Create an NDEF message from raw bytes. |
| * <p> |
| * Validation is performed to make sure the Record format headers are valid, |
| * and the ID + TYPE + PAYLOAD fields are of the correct size. |
| * @throws FormatException |
| */ |
| public NdefMessage(byte[] data) throws FormatException { |
| mRecords = null; // stop compiler complaints about final field |
| if (parseNdefMessage(data) == -1) { |
| throw new FormatException("Error while parsing NDEF message"); |
| } |
| } |
| |
| /** |
| * Create an NDEF message from NDEF records. |
| */ |
| public NdefMessage(NdefRecord[] records) { |
| mRecords = new NdefRecord[records.length]; |
| System.arraycopy(records, 0, mRecords, 0, records.length); |
| } |
| |
| /** |
| * Get the NDEF records inside this NDEF message. |
| * |
| * @return array of zero or more NDEF records. |
| */ |
| public NdefRecord[] getRecords() { |
| return mRecords.clone(); |
| } |
| |
| /** |
| * Returns a byte array representation of this entire NDEF message. |
| */ |
| public byte[] toByteArray() { |
| //TODO: allocate the byte array once, copy each record once |
| //TODO: process MB and ME flags outside loop |
| if ((mRecords == null) || (mRecords.length == 0)) |
| return new byte[0]; |
| |
| byte[] msg = {}; |
| |
| for (int i = 0; i < mRecords.length; i++) { |
| byte[] record = mRecords[i].toByteArray(); |
| byte[] tmp = new byte[msg.length + record.length]; |
| |
| /* Make sure the Message Begin flag is set only for the first record */ |
| if (i == 0) { |
| record[0] |= FLAG_MB; |
| } else { |
| record[0] &= ~FLAG_MB; |
| } |
| |
| /* Make sure the Message End flag is set only for the last record */ |
| if (i == (mRecords.length - 1)) { |
| record[0] |= FLAG_ME; |
| } else { |
| record[0] &= ~FLAG_ME; |
| } |
| |
| System.arraycopy(msg, 0, tmp, 0, msg.length); |
| System.arraycopy(record, 0, tmp, msg.length, record.length); |
| |
| msg = tmp; |
| } |
| |
| return msg; |
| } |
| |
| @Override |
| public int describeContents() { |
| return 0; |
| } |
| |
| @Override |
| public void writeToParcel(Parcel dest, int flags) { |
| dest.writeInt(mRecords.length); |
| dest.writeTypedArray(mRecords, flags); |
| } |
| |
| public static final Parcelable.Creator<NdefMessage> CREATOR = |
| new Parcelable.Creator<NdefMessage>() { |
| @Override |
| public NdefMessage createFromParcel(Parcel in) { |
| int recordsLength = in.readInt(); |
| NdefRecord[] records = new NdefRecord[recordsLength]; |
| in.readTypedArray(records, NdefRecord.CREATOR); |
| return new NdefMessage(records); |
| } |
| @Override |
| public NdefMessage[] newArray(int size) { |
| return new NdefMessage[size]; |
| } |
| }; |
| |
| private native int parseNdefMessage(byte[] data); |
| } |