Value (Neo4j Java Driver 1.3.0 API)

All Superinterfaces:

MapAccessor, MapAccessorWithDefaultValue
```
@Immutable
public interface Value
extends MapAccessor, MapAccessorWithDefaultValue
```
A unit of data that adheres to the Neo4j type system. This interface describes a number of isType methods along with typeValue methods. The first set of these correlate with types from the Neo4j Type System and are used to determine which Neo4j type is represented. The second set of methods perform coercions to Java types (wherever possible). For example, a common String value should be tested for using isString and extracted using stringValue.
Navigating a tree structure
Because Neo4j often handles dynamic structures, this interface is designed to help you handle such structures in Java. Specifically, Value lets you navigate arbitrary tree structures without having to resort to type casting. Given a tree structure like:
```
 {
   users : [
     { name : "Anders" },
     { name : "John" }
   ]
 }
 
 
```
You can retrieve the name of the second user, John, like so:
```
 String username = value.get("users").get(1).get("name").asString();
 
 
```
You can also easily iterate over the users:
```
 List<String> names = new LinkedList<>();
 for(Value user : value.get("users").values() )
 {
     names.add(user.get("name").asString());
 }
 
 
```
Since:

1.0

Method Summary

Methods
Modifier and Type	Method and Description
`boolean`	`asBoolean()`
`double`	`asDouble()` Returns a Java double if no precision is lost in the conversion.
`Entity`	`asEntity()`
`float`	`asFloat()` Returns a Java float if no precision is lost in the conversion.
`int`	`asInt()` Returns a Java int if no precision is lost in the conversion.
`List<Object>`	`asList()` If the underlying type can be viewed as a list, returns a java list of values, where each value has been converted using `asObject()`.
`<T> List<T>`	`asList(Function<Value,T> mapFunction)`
`long`	`asLong()` Returns a Java long if no precision is lost in the conversion.
`Node`	`asNode()`
`Number`	`asNumber()`
`Object`	`asObject()` This returns a java standard library representation of the underlying value, using a java type that is "sensible" given the underlying type.
`Path`	`asPath()`
`Relationship`	`asRelationship()`
`String`	`asString()`
`boolean`	`equals(Object other)`
`Value`	`get(int index)` Retrieve the value at the given index
`int`	`hashCode()`
`boolean`	`hasType(Type type)` Test if this value is a value of the given type
`boolean`	`isEmpty()` If this value represents a list or map, test if the collection is empty.
`boolean`	`isFalse()`
`boolean`	`isNull()`
`boolean`	`isTrue()`
`Iterable<String>`	`keys()` If the underlying value supports `key-based indexing`, return an iterable of the keys in the map, this applies to `map`, `node` and `TypeSystem.RELATIONSHIP()` relationship} values.
`int`	`size()` If the underlying value is a collection type, return the number of values in the collection.
`String`	`toString()`
`Type`	`type()`

Methods inherited from interface org.neo4j.driver.v1.types.MapAccessor
asMap, asMap, containsKey, get, values, values

Methods inherited from interface org.neo4j.driver.v1.types.MapAccessorWithDefaultValue
get, get, get, get, get, get, get, get, get, get, get, get, get, get, get, get, get

- Method Detail
  - size
```
int size()
```
    If the underlying value is a collection type, return the number of values in the collection.
    For TypeSystem.LIST() list} values, this will return the size of the list.
    For map values, this will return the number of entries in the map.
    For node and TypeSystem.RELATIONSHIP() relationship} values, this will return the number of properties.
    For path values, this returns the length (number of relationships) in the path.
    
    Specified by:
    
    size in interface MapAccessor
    
    Returns:
    the number of values in an underlying collection
  - isEmpty
```
boolean isEmpty()
```
    If this value represents a list or map, test if the collection is empty.
    
    Returns:
    true if size() is 0, otherwise false
  - keys
```
Iterable<String> keys()
```
    If the underlying value supports key-based indexing, return an iterable of the keys in the map, this applies to map, node and TypeSystem.RELATIONSHIP() relationship} values.
    
    Specified by:
    
    keys in interface MapAccessor
    
    Returns:
    the keys in the value
  - get
```
Value get(int index)
```
    Retrieve the value at the given index
    
    Parameters:
    index - the index of the value
    
    Returns:
    the value or a NullValue if the index is out of bounds
    
    Throws:
    
    ClientException - if record has not been initialized
  - type
```
@Experimental
Type type()
```
    Returns:
    The type of this value as defined in the Neo4j type system
  - hasType
```
@Experimental
boolean hasType(Type type)
```
    Test if this value is a value of the given type
    
    Parameters:
    type - the given type
    
    Returns:
    type.isTypeOf( this )
  - isTrue
```
boolean isTrue()
```
    Returns:
    true if the value is a Boolean value and has the value True.
  - isFalse
```
boolean isFalse()
```
    Returns:
    true if the value is a Boolean value and has the value False.
  - isNull
```
boolean isNull()
```
    Returns:
    true if the value is a Null, otherwise false
  - asObject
```
Object asObject()
```
    This returns a java standard library representation of the underlying value, using a java type that is "sensible" given the underlying type. The mapping for common types is as follows:
    - TypeSystem.INTEGER() - Long
    - TypeSystem.FLOAT() - Double
    - TypeSystem.NUMBER() - Number
    - TypeSystem.STRING() - String
    - TypeSystem.BOOLEAN() - Boolean
    - TypeSystem.NULL() - null
    - TypeSystem.NODE() - Node
    - TypeSystem.RELATIONSHIP() - Relationship
    - TypeSystem.PATH() - Path
    - TypeSystem.MAP() - Map
    - TypeSystem.LIST() - List
    Note that the types in TypeSystem refers to the Neo4j type system where TypeSystem.INTEGER() and TypeSystem.FLOAT() are both 64-bit precision. This is why these types return java Long and Double, respectively.
    Returns:
    the value as a Java Object
  - asBoolean
```
boolean asBoolean()
```
    Returns:
    the value as a Java boolean, if possible.
    
    Throws:
    
    Uncoercible - if value types are incompatible.
  - asString
```
String asString()
```
    Returns:
    the value as a Java String, if possible.
    
    Throws:
    
    Uncoercible - if value types are incompatible.
  - asNumber
```
Number asNumber()
```
    Returns:
    the value as a Java Number, if possible.
    
    Throws:
    
    Uncoercible - if value types are incompatible.
  - asLong
```
long asLong()
```
    Returns a Java long if no precision is lost in the conversion.
    
    Returns:
    the value as a Java long.
    
    Throws:
    
    LossyCoercion - if it is not possible to convert the value without loosing precision.
    
    Uncoercible - if value types are incompatible.
  - asInt
```
int asInt()
```
    Returns a Java int if no precision is lost in the conversion.
    
    Returns:
    the value as a Java int.
    
    Throws:
    
    LossyCoercion - if it is not possible to convert the value without loosing precision.
    
    Uncoercible - if value types are incompatible.
  - asDouble
```
double asDouble()
```
    Returns a Java double if no precision is lost in the conversion.
    
    Returns:
    the value as a Java double.
    
    Throws:
    
    LossyCoercion - if it is not possible to convert the value without loosing precision.
    
    Uncoercible - if value types are incompatible.
  - asFloat
```
float asFloat()
```
    Returns a Java float if no precision is lost in the conversion.
    
    Returns:
    the value as a Java float.
    
    Throws:
    
    LossyCoercion - if it is not possible to convert the value without loosing precision.
    
    Uncoercible - if value types are incompatible.
  - asList
```
List<Object> asList()
```
    If the underlying type can be viewed as a list, returns a java list of values, where each value has been converted using asObject().
    
    Returns:
    the value as a Java list of values, if possible
    See Also:
    asObject()
  - asList
```
<T> List<T> asList(Function<Value,T> mapFunction)
```
    Type Parameters:
    T - the type of target list elements
    Parameters:
    mapFunction - a function to map from Value to T. See Values for some predefined functions, such as Values.ofBoolean(), Values.ofList(Function).
    
    Returns:
    the value as a list of T obtained by mapping from the list elements, if possible
    See Also:
    for a long list of built-in conversion functions
  - asEntity
```
Entity asEntity()
```
    Returns:
    the value as a Entity, if possible.
    
    Throws:
    
    Uncoercible - if value types are incompatible.
  - asNode
```
Node asNode()
```
    Returns:
    the value as a Node, if possible.
    
    Throws:
    
    Uncoercible - if value types are incompatible.
  - asRelationship
```
Relationship asRelationship()
```
    Returns:
    the value as a Relationship, if possible.
    
    Throws:
    
    Uncoercible - if value types are incompatible.
  - asPath
```
Path asPath()
```
    Returns:
    the value as a Path, if possible.
    
    Throws:
    
    Uncoercible - if value types are incompatible.
  - equals
```
boolean equals(Object other)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
int hashCode()
```
    Overrides:
    
    hashCode in class Object
  - toString
```
String toString()
```
    Overrides:
    
    toString in class Object

Interface Value

Navigating a tree structure

Method Summary

Methods inherited from interface org.neo4j.driver.v1.types.MapAccessor

Methods inherited from interface org.neo4j.driver.v1.types.MapAccessorWithDefaultValue

Method Detail

size

isEmpty

keys

get

type

hasType

isTrue

isFalse

isNull

asObject

asBoolean

asString

asNumber

asLong

asInt

asDouble

asFloat

asList

asList

asEntity

asNode

asRelationship

asPath

equals

hashCode

toString