程序包 ohos.data.distributed.common

类 FieldNode

java.lang.Object

ohos.data.distributed.common.FieldNode

public class FieldNode
extends Object

Represents a node of a Schema instance.

Through the Schema instance, you can define the fields contained in the values stored in a database.

A FieldNode of the Schema instance is either a leaf or a non-leaf node.

The leaf node must have a value; the non-leaf node must have a child FieldNode.

从以下版本开始:

3

SystemCapability

SystemCapability.Data#DATA_DISTRIBUTEDDATAMGR

构造器概要

构造器

构造器	说明
FieldNode(String fieldName)	A constructor used to create a FieldNode instance with the specified field.

方法概要

限定符和类型	方法	说明
boolean	appendChild(FieldNode fieldNode)	Adds a child node to this FieldNode.
List<FieldNode>	getChildren()	Obtains the list of child nodes of this FieldNode.
Object	getDefaultValue()	Obtains the default field value.
String	getFieldName()	Obtains the field name.
FieldValueType	getType()	Obtains the field value type.
boolean	isNullable()	Checks whether field value is nullable.
boolean	setDefault(boolean defaultValue)	Sets the default boolean field value.
boolean	setDefault(double defaultValue)	Set the default double value of this field value.
boolean	setDefault(int defaultValue)	Sets the default int field value.
boolean	setDefault(long defaultValue)	Sets the default long field value.
boolean	setDefault(String defaultValue)	Sets the default string field value.
boolean	setDefaultNull()	Sets the default field value to null.
boolean	setNullable(boolean isNullable)	Sets whether field value is nullable.
void	setType(FieldValueType type)	Sets the field value type.

从类继承的方法 java.lang.Object

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

构造器详细资料

FieldNode

public FieldNode(String fieldName)

A constructor used to create a FieldNode instance with the specified field.

The initialized FieldNode instance contains no value or child node.

参数:

fieldName - Indicates the field name.

从以下版本开始:

3

方法详细资料

getFieldName

public String getFieldName()

Obtains the field name.

返回:

Returns the field name.

从以下版本开始:

3

appendChild

public boolean appendChild(FieldNode fieldNode)

Adds a child node to this FieldNode.

Adding a child node makes this node a non-leaf node. Field value will be ignored if it has child node.

参数:

fieldNode - The field node to append.

返回:

Returns true if the child node is successfully added to this FieldNode; returns false otherwise.

从以下版本开始:

3

getChildren

public List<FieldNode> getChildren()

Obtains the list of child nodes of this FieldNode.

This method only applies to non-leaf nodes.

返回:

Returns the list of child nodes of this FieldNode.

从以下版本开始:

3

getType

public FieldValueType getType()

Obtains the field value type.

返回:

Returns the field value type.

从以下版本开始:

3

setType

public void setType(FieldValueType type)

Sets the field value type.

参数:

type - Indicates the field value type to set.

从以下版本开始:

3

isNullable

public boolean isNullable()

Checks whether field value is nullable.

返回:

Returns true if field value is nullable; returns false otherwise.

从以下版本开始:

3

setNullable

public boolean setNullable(boolean isNullable)

Sets whether field value is nullable.

参数:

isNullable - Specifies whether field value is nullable. Value true indicates that field value is nullable, and value false indicates not.

返回:

Returns true if set successfully; returns false otherwise.

从以下版本开始:

3

getDefaultValue

public Object getDefaultValue()

Obtains the default field value.

返回:

Returns the default field value.

从以下版本开始:

3

setDefault

public boolean setDefault(String defaultValue)

Sets the default string field value.

参数:

defaultValue - Indicates the default string field value to set.

返回:

Returns true if the default string field value is set successfully; returns false otherwise.

从以下版本开始:

3

setDefault

public boolean setDefault(int defaultValue)

Sets the default int field value.

参数:

defaultValue - Indicates the default int field value to set.

返回:

Returns true if the default int field value is set successfully; returns false otherwise.

从以下版本开始:

3

setDefault

public boolean setDefault(long defaultValue)

Sets the default long field value.

参数:

defaultValue - Indicates the default long field value to set.

返回:

Returns true if the default long field value is set successfully; returns false otherwise.

从以下版本开始:

3

setDefault

public boolean setDefault(double defaultValue)

Set the default double value of this field value.

参数:

defaultValue - default value

返回:

true succeed; false failed

从以下版本开始:

3

setDefault

public boolean setDefault(boolean defaultValue)

Sets the default boolean field value.

参数:

defaultValue - Indicates the default boolean field value to set.

返回:

Returns true if the default boolean field value is set successfully; returns false otherwise.

从以下版本开始:

3

setDefaultNull

public boolean setDefaultNull()

Sets the default field value to null.

返回:

Returns true if the default boolean field value is set successfully; returns false otherwise.

从以下版本开始:

3