程序包 ohos.data.distributed.common

类 Value

java.lang.Object

ohos.data.distributed.common.Value

public class Value
extends Object

Obtains Value objects stored in a KvStore database.

从以下版本开始:

1

SystemCapability

SystemCapability.Data#DATA_DISTRIBUTEDDATAMGR

方法概要

限定符和类型	方法	说明
boolean	equals(Object object)	Indicates whether some other object is "equal to" this one.
static Value	get(byte[] value)	Obtains Value objects of the byte array type.
static Value	get(double value)	Obtains Value objects of the double type.
static Value	get(float value)	Obtains Value objects of the float type.
static Value	get(int value)	Obtains Value objects of the int type.
static Value	get(String value)	Obtains Value objects of the string type.
byte[]	getByteArray()	Obtains values of the byte array type.
double	getDouble()	Obtains values of the double type.
float	getFloat()	Obtains values of the float type.
int	getInt()	Obtains values of the int type.
String	getString()	Obtains values of the string type.
int	hashCode()	Returns a hash code value for the object.

从类继承的方法 java.lang.Object

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

方法详细资料

get

public static Value get(String value)

Obtains Value objects of the string type.

参数:

value - Indicates the input value.

返回:

Returns Value objects of the string type.

抛出:

KvStoreException - Throws this exception if the input value is not in UTF-8 format.

从以下版本开始:

1

get

public static Value get(int value)

Obtains Value objects of the int type.

参数:

value - Indicates the input value.

返回:

Returns Value objects of the int type.

从以下版本开始:

1

get

public static Value get(float value)

Obtains Value objects of the float type.

参数:

value - Indicates the input value.

返回:

Returns Value objects of the float type.

从以下版本开始:

1

get

public static Value get(double value)

Obtains Value objects of the double type.

参数:

value - Indicates the input value.

返回:

Returns Value objects of the double type.

从以下版本开始:

1

get

public static Value get(byte[] value)

Obtains Value objects of the byte array type.

参数:

value - Indicates the input value.

返回:

Returns Value objects of the byte array type.

从以下版本开始:

1

getDouble

public double getDouble()

Obtains values of the double type.

返回:

Returns values of the double type.

从以下版本开始:

1

getString

public String getString()

Obtains values of the string type.

返回:

Returns values of the string type.

抛出:

KvStoreException - Throws this exception if the input value is not in UTF-8 format.

从以下版本开始:

1

getInt

public int getInt()

Obtains values of the int type.

返回:

Returns values of the int type.

抛出:

KvStoreException - Throws this exception if no value of the int type is found.

从以下版本开始:

1

getFloat

public float getFloat()

Obtains values of the float type.

返回:

Returns values of the float type.

抛出:

KvStoreException - Throws this exception if no value of the float type is found.

从以下版本开始:

1

getByteArray

public byte[] getByteArray()

Obtains values of the byte array type.

返回:

Returns values of the byte array type.

抛出:

KvStoreException - Throws this exception if no value of the byte array type is found.

从以下版本开始:

1

equals

public boolean equals(Object object)

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:

object - 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

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)