NdefRecord

See also:

• NfcAdapter.ACTION_NDEF_DISCOVERED
• NdefMessage

TNF_ABSOLUTE_URI

public static final short TNF_ABSOLUTE_URI

Indicates the type field contains an absolute-URI BNF construct defined by RFC 3986.

When creating new records prefer createUri(Uri), since it offers more compact URI encoding (#RTD_URI allows compression of common URI prefixes).

Constant Value: 3 (0x00000003)

TNF_EMPTY

public static final short TNF_EMPTY

Indicates the record is empty.

Type, id and payload fields are empty in a TNF_EMPTY record.

Constant Value: 0 (0x00000000)

TNF_EXTERNAL_TYPE

public static final short TNF_EXTERNAL_TYPE

Indicates the type field contains an external type name.

Used to encode custom payloads. When creating new records use the helper createExternal(String, String, byte).

The external-type RTD format is specified in NFCForum-TS-RTD_1.0.

Note this TNF should not be used with RTD_TEXT or RTD_URI constants. Those are well known RTD constants, not external RTD constants.

Constant Value: 4 (0x00000004)

TNF_MIME_MEDIA

public static final short TNF_MIME_MEDIA

Indicates the type field contains a media-type BNF construct, defined by RFC 2046.

Use this with MIME type names such as "image/jpeg", or using the helper createMime(String, byte).

Constant Value: 2 (0x00000002)

TNF_UNCHANGED

public static final short TNF_UNCHANGED

Indicates the payload is an intermediate or final chunk of a chunked NDEF Record.

TNF_UNCHANGED can not be used with this class since all NdefRecords are already unchunked, however they may appear in the binary format.

Constant Value: 6 (0x00000006)

TNF_UNKNOWN

public static final short TNF_UNKNOWN

Indicates the payload type is unknown.

NFC Forum explains this should be treated similarly to the "application/octet-stream" MIME type. The payload type is not explicitly encoded within the record.

The type field is empty in an TNF_UNKNOWN record.

Constant Value: 5 (0x00000005)

TNF_WELL_KNOWN

public static final short TNF_WELL_KNOWN

Indicates the type field contains a well-known RTD type name.

Use this tnf with RTD types such as RTD_TEXT, RTD_URI.

The RTD type name format is specified in NFCForum-TS-RTD_1.0.

Constant Value: 1 (0x00000001)

CREATOR

public static final Creator<NdefRecord> CREATOR

RTD_ALTERNATIVE_CARRIER

public static final byte[] RTD_ALTERNATIVE_CARRIER

RTD Alternative Carrier type. For use with TNF_WELL_KNOWN.

RTD_HANDOVER_CARRIER

public static final byte[] RTD_HANDOVER_CARRIER

RTD Handover Carrier type. For use with TNF_WELL_KNOWN.

RTD_HANDOVER_REQUEST

public static final byte[] RTD_HANDOVER_REQUEST

RTD Handover Request type. For use with TNF_WELL_KNOWN.

RTD_HANDOVER_SELECT

public static final byte[] RTD_HANDOVER_SELECT

RTD Handover Select type. For use with TNF_WELL_KNOWN.

RTD_SMART_POSTER

public static final byte[] RTD_SMART_POSTER

RTD Smart Poster type. For use with TNF_WELL_KNOWN.

RTD_TEXT

public static final byte[] RTD_TEXT

RTD Text type. For use with TNF_WELL_KNOWN.

RTD_URI

public static final byte[] RTD_URI

RTD URI type. For use with TNF_WELL_KNOWN.

NdefRecord

public NdefRecord (byte[] data)

This constructor is deprecated.
use NdefMessage.NdefMessage(byte[]) instead.

Construct an NDEF Record from raw bytes.

This method is deprecated, use NdefMessage.NdefMessage(byte[]) instead. This is because it does not make sense to parse a record: the NDEF binary format is only defined for a message, and the record flags MB and ME do not make sense outside of the context of an entire message.

This implementation will attempt to parse a single record by ignoring the MB and ME flags, and otherwise following the rules of NdefMessage.NdefMessage(byte[]).

NdefRecord

public NdefRecord (short tnf, 
                byte[] type, 
                byte[] id, 
                byte[] payload)

Construct an NDEF Record from its component fields.

Recommend to use helpers such as {#createUri} or {createExternal(String, String, byte) where possible, since they perform stricter validation that the record is correctly formatted as per NDEF specifications. However if you know what you are doing then this constructor offers the most flexibility.

An NdefRecord represents a logical (complete) record, and cannot represent NDEF Record chunks.

Basic validation of the tnf, type, id and payload is performed as per the following rules:

• The tnf paramter must be a 3-bit value.
• Records with a tnf of TNF_EMPTY cannot have a type, id or payload.
• Records with a tnf of TNF_UNKNOWN or 0x07 cannot have a type.
• Records with a tnf of TNF_UNCHANGED are not allowed since this class only represents complete (unchunked) records.

If any of the above validation steps fail then IllegalArgumentException is thrown.

Deep inspection of the type, id and payload fields is not performed, so it is possible to create NDEF Records that conform to section 3.2.6 but fail other more strict NDEF specification requirements. For example, the payload may be invalid given the tnf and type.

To omit a type, id or payload field, set the parameter to an empty byte array or null.

createApplicationRecord

public static NdefRecord createApplicationRecord (String packageName)

Create a new Android Application Record (AAR).

This record indicates to other Android devices the package that should be used to handle the entire NDEF message. You can embed this record anywhere into your message to ensure that the intended package receives the message.

When an Android device dispatches an NdefMessage containing one or more Android application records, the applications contained in those records will be the preferred target for the NfcAdapter.ACTION_NDEF_DISCOVERED intent, in the order in which they appear in the message. This dispatch behavior was first added to Android in Ice Cream Sandwich.

If none of the applications have a are installed on the device, a Market link will be opened to the first application.

Note that Android application records do not overrule applications that have called NfcAdapter.enableForegroundDispatch.

createExternal

public static NdefRecord createExternal (String domain, 
                String type, 
                byte[] data)

Create a new NDEF Record containing external (application-specific) data.

Use this method to encode application specific data into an NDEF Record. The data is typed by a domain name (usually your Android package name) and a domain-specific type. This data is packaged into a "NFC Forum External Type" NDEF Record.

NFC Forum requires that the domain and type used in an external record are treated as case insensitive, however Android intent filtering is always case sensitive. So this method will force the domain and type to lower-case before creating the NDEF Record.

The unchecked exception IllegalArgumentException will be thrown if the domain and type have serious problems, for example if either field is empty, so always catch this exception if you are passing user-generated data into this method.

There are no such restrictions on the payload data.

For efficiency, This method might not make an internal copy of the data byte array, so take care not to modify the data byte array while still using the returned NdefRecord. Reference specification: NFCForum-TS-RTD_1.0

createMime

public static NdefRecord createMime (String mimeType, 
                byte[] mimeData)

Create a new NDEF Record containing MIME data.

Use this method to encode MIME-typed data into an NDEF Record, such as "text/plain", or "image/jpeg".

The mimeType parameter will be normalized with Intent.normalizeMimeType to follow Android best practices for intent filtering, for example to force lower-case. However the unchecked exception IllegalArgumentException may be thrown if the mimeType parameter has serious problems, for example if it is empty, so always catch this exception if you are passing user-generated data into this method.

For efficiency, This method might not make an internal copy of the mimeData byte array, so take care not to modify the mimeData byte array while still using the returned NdefRecord.

createTextRecord

public static NdefRecord createTextRecord (String languageCode, 
                String text)

Create a new NDEF record containing UTF-8 text data.

The caller can either specify the language code for the provided text, or otherwise the language code corresponding to the current default locale will be used. Reference specification: NFCForum-TS-RTD_Text_1.0

createUri

public static NdefRecord createUri (Uri uri)

Create a new NDEF Record containing a URI.

Use this method to encode a URI (or URL) into an NDEF Record.

Uses the well known URI type representation: TNF_WELL_KNOWN and RTD_URI. This is the most efficient encoding of a URI into NDEF.

The uri parameter will be normalized with Uri.normalizeScheme to set the scheme to lower case to follow Android best practices for intent filtering. However the unchecked exception IllegalArgumentException may be thrown if the uri parameter has serious problems, for example if it is empty, so always catch this exception if you are passing user-generated data into this method.

Reference specification: NFCForum-TS-RTD_URI_1.0

createUri

public static NdefRecord createUri (String uriString)

Create a new NDEF Record containing a URI.

Use this method to encode a URI (or URL) into an NDEF Record.

Uses the well known URI type representation: TNF_WELL_KNOWN and RTD_URI. This is the most efficient encoding of a URI into NDEF.

The uriString parameter will be normalized with Uri.normalizeScheme to set the scheme to lower case to follow Android best practices for intent filtering. However the unchecked exception IllegalArgumentException may be thrown if the uriString parameter has serious problems, for example if it is empty, so always catch this exception if you are passing user-generated data into this method.

Reference specification: NFCForum-TS-RTD_URI_1.0

describeContents

public int describeContents ()

Describe the kinds of special objects contained in this Parcelable instance's marshaled representation. For example, if the object will include a file descriptor in the output of writeToParcel(android.os.Parcel, int), the return value of this method must include the CONTENTS_FILE_DESCRIPTOR bit.

equals

public boolean equals (Object obj)

Returns true if the specified NDEF Record contains identical tnf, type, id and payload fields.

getId

public byte[] getId ()

Returns the variable length ID.

Returns an empty byte array if this record does not have an id field.

getPayload

public byte[] getPayload ()

Returns the variable length payload.

Returns an empty byte array if this record does not have a payload field.

getTnf

public short getTnf ()

Returns the 3-bit TNF.

TNF is the top-level type.

getType

public byte[] getType ()

Returns the variable length Type field.

This should be used in conjunction with the TNF field to determine the payload format.

Returns an empty byte array if this record does not have a type field.

hashCode

public int hashCode ()

Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided by HashMap.

The general contract of hashCode is:

• Whenever it is invoked on the same object more than once during an execution of a Java application, the hashCode method must consistently return the same integer, provided no information used in equals comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application.
• If two objects are equal according to the equals method, then calling the hashCode method on each of the two objects must produce the same integer result.
• It is not required that if two objects are unequal according to the equals method, then calling the hashCode method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.

toByteArray

public byte[] toByteArray ()

This method was deprecated in API level 16.
use NdefMessage.toByteArray() instead

Return this NDEF Record as a byte array.

This method is deprecated, use NdefMessage.toByteArray instead. This is because the NDEF binary format is not defined for a record outside of the context of a message: the MB and ME flags cannot be set without knowing the location inside a message.

This implementation will attempt to serialize a single record by always setting the MB and ME flags (in other words, assume this is a single-record NDEF Message).

toMimeType

public String toMimeType ()

Map this record to a MIME type, or return null if it cannot be mapped.

Currently this method considers all TNF_MIME_MEDIA records to be MIME records, as well as some TNF_WELL_KNOWN records such as RTD_TEXT. If this is a MIME record then the MIME type as string is returned, otherwise null is returned.

This method does not perform validation that the MIME type is actually valid. It always attempts to return a string containing the type if this is a MIME record.

The returned MIME type will by normalized to lower-case using Intent.normalizeMimeType.

The MIME payload can be obtained using getPayload().

toString

public String toString ()

Returns a string representation of the object.

toUri

public Uri toUri ()

Map this record to a URI, or return null if it cannot be mapped.

Currently this method considers the following to be URI records:

• TNF_ABSOLUTE_URI records.
• TNF_WELL_KNOWN with a type of RTD_URI.
• TNF_WELL_KNOWN with a type of RTD_SMART_POSTER and containing a URI record in the NDEF message nested in the payload.
• TNF_EXTERNAL_TYPE records.

This method does not perform validation that the URI is actually valid: it always attempts to create and return a URI if this record appears to be a URI record by the above rules.

The returned URI will be normalized to have a lower case scheme using Uri.normalizeScheme.

writeToParcel

public void writeToParcel (Parcel dest, 
                int flags)

Flatten this object in to a Parcel.