程序包 ohos.nfc.tag

类 NdefMessage

java.lang.Object

ohos.nfc.tag.NdefMessage

所有已实现的接口:

Sequenceable

public class NdefMessage
extends Object
implements Sequenceable

Represents an NDEF message, which is a container for one or more MessageRecord objects.

从以下版本开始:

3

SystemCapability

SystemCapability.Communication.NFC

嵌套类概要

从接口继承的嵌套类/接口 ohos.utils.Sequenceable

Sequenceable.Producer<T>

构造器概要

构造器

构造器	说明
NdefMessage(byte[] data)	Constructs an NDEF message by parsing raw bytes.
NdefMessage(MessageRecord[] records)	Constructs an NDEF message from one or more NDEF records.

方法概要

限定符和类型	方法	说明
boolean	equals(Object obj)	Indicates whether some other object is "equal to" this one.
int	getAllRecordsLength()	Obtains the length of this NDEF message.
MessageRecord[]	getRecords()	Obtains the NDEF records in this NDEF message.
int	hashCode()	Returns a hash code value for the object.
boolean	marshalling(Parcel out)	Marshals this Sequenceable object into a Parcel.
boolean	unmarshalling(Parcel in)	Unmarshals this Sequenceable object from a Parcel.

从类继承的方法 java.lang.Object

clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

从接口继承的方法 ohos.utils.Sequenceable

hasFileDescriptor

构造器详细资料

NdefMessage

public NdefMessage(byte[] data)
            throws IllegalArgumentException

Constructs an NDEF message by parsing raw bytes.

参数:

data - Indicates the raw bytes to parse.

抛出:

IllegalArgumentException - if the data cannot be parsed.

从以下版本开始:

4

NdefMessage

public NdefMessage(MessageRecord[] records)

Constructs an NDEF message from one or more NDEF records.

参数:

records - Indicates one or more NDEF records.

从以下版本开始:

3

方法详细资料

getRecords

public MessageRecord[] getRecords()

Obtains the NDEF records in this NDEF message.

返回:

Returns an array of one or more NDEF records.

从以下版本开始:

3

getAllRecordsLength

public int getAllRecordsLength()

Obtains the length of this NDEF message.

返回:

Returns the length of this NDEF message.

从以下版本开始:

3

hashCode

public int hashCode()

从类复制的说明: Object

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(Object) 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 Object.equals(java.lang.Object) 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.

As much as is reasonably practical, the hashCode method defined by class Object does return distinct integers for distinct objects. (This is typically implemented by converting the internal address of the object into an integer, but this implementation technique is not required by the Java™ programming language.)

覆盖:

hashCode 在类中 Object

返回:

a hash code value for this object.

另请参阅:

Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)

equals

public boolean equals(Object obj)

从类复制的说明: Object

Indicates whether some other object is "equal to" this one.

The equals method implements an equivalence relation on non-null object references:

• It is reflexive: for any non-null reference value x, x.equals(x) should return true.
• It is symmetric: for any non-null reference values x and y, x.equals(y) should return true if and only if y.equals(x) returns true.
• It is transitive: for any non-null reference values x, y, and z, if x.equals(y) returns true and y.equals(z) returns true, then x.equals(z) should return true.
• It is consistent: for any non-null reference values x and y, multiple invocations of x.equals(y) consistently return true or consistently return false, provided no information used in equals comparisons on the objects is modified.
• For any non-null reference value x, x.equals(null) should return false.

The equals method for class Object implements the most discriminating possible equivalence relation on objects; that is, for any non-null reference values x and y, this method returns true if and only if x and y refer to the same object (x == y has the value true).

Note that it is generally necessary to override the hashCode method whenever this method is overridden, so as to maintain the general contract for the hashCode method, which states that equal objects must have equal hash codes.

覆盖:

equals 在类中 Object

参数:

obj - the reference object with which to compare.

返回:

true if this object is the same as the obj argument; false otherwise.

另请参阅:

Object.hashCode(), HashMap

marshalling

public boolean marshalling(Parcel out)

从接口复制的说明: Sequenceable

Marshals this Sequenceable object into a Parcel.

指定者:

marshalling 在接口中 Sequenceable

参数:

out - Indicates the Parcel object to which the Sequenceable object will be marshaled..

返回:

Returns true if the marshalling is successful; returns false otherwise.

unmarshalling

public boolean unmarshalling(Parcel in)

从接口复制的说明: Sequenceable

Unmarshals this Sequenceable object from a Parcel.

指定者:

unmarshalling 在接口中 Sequenceable

参数:

in - Indicates the Parcel object into which the Sequenceable object has been marshaled.

返回:

Returns true if the unmarshalling is successful; returns false otherwise.