java.lang.Object
- com.restfb.json.JsonValue

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

JsonArray, JsonObject
```
public abstract class JsonValue
extends Object
implements Serializable
```
Represents a JSON value. This can be a JSON object, an array, a number, a string, or one of the literals true, false, and null.
The literals true, false, and null are represented by the constants Json.TRUE, Json.FALSE, and Json.NULL.

JSON objects and arrays are represented by the subtypes JsonObject and JsonArray. Instances of these types can be created using the public constructors of these classes.

Instances that represent JSON numbers, strings and boolean values can be created using the static factory methods Json.value(String), Json.value(long), Json.value(double), etc.

In order to find out whether an instance of this class is of a certain type, the methods isObject(), isArray(), isString(), isNumber() etc. can be used.

If the type of a JSON value is known, the methods asObject(), asArray(), asString(), asInt(), etc. can be used to get this value directly in the appropriate target type.

This class is not supposed to be extended by clients.

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type	Field	Description
`protected static String`	`ARRAY_IS_NULL`
`protected static String`	`NAME_IS_NULL`
`protected static String`	`OBJECT_IS_NULL`
`protected static String`	`STRING_IS_NULL`
`protected static String`	`VALUE_IS_NULL`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`JsonArray`	`asArray()`	Returns this JSON value as `JsonArray`, assuming that this value represents a JSON array.
`boolean`	`asBoolean()`	Returns this JSON value as a `boolean` value, assuming that this value is either `true` or `false`.
`double`	`asDouble()`	Returns this JSON value as a `double` value, assuming that this value represents a JSON number.
`float`	`asFloat()`	Returns this JSON value as a `float` value, assuming that this value represents a JSON number.
`int`	`asInt()`	Returns this JSON value as an `int` value, assuming that this value represents a JSON number that can be interpreted as Java `int`.
`long`	`asLong()`	Returns this JSON value as a `long` value, assuming that this value represents a JSON number that can be interpreted as Java `long`.
`JsonObject`	`asObject()`	Returns this JSON value as `JsonObject`, assuming that this value represents a JSON object.
`String`	`asString()`	Returns this JSON value as String, assuming that this value represents a JSON string.
`boolean`	`equals(Object object)`	Indicates whether some other object is "equal to" this one according to the contract specified in `Object.equals(Object)`.
`int`	`hashCode()`
`boolean`	`isArray()`	Detects whether this value represents a JSON array.
`boolean`	`isBoolean()`	Detects whether this value represents a boolean value.
`boolean`	`isFalse()`	Detects whether this value represents the JSON literal `false`.
`boolean`	`isNull()`	Detects whether this value represents the JSON literal `null`.
`boolean`	`isNumber()`	Detects whether this value represents a JSON number.
`boolean`	`isObject()`	Detects whether this value represents a JSON object.
`boolean`	`isString()`	Detects whether this value represents a JSON string.
`boolean`	`isTrue()`	Detects whether this value represents the JSON literal `true`.
`String`	`toString()`	Returns the JSON string for this value in its minimal form, without any additional whitespace.
`String`	`toString(WriterConfig config)`	Returns the JSON string for this value using the given formatting.
`void`	`writeTo(Writer writer)`	Writes the JSON representation of this value to the given writer in its minimal form, without any additional whitespace.
`void`	`writeTo(Writer writer, WriterConfig config)`	Writes the JSON representation of this value to the given writer using the given formatting.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - STRING_IS_NULL
```
protected static final String STRING_IS_NULL
```
    See Also:
    
    Constant Field Values
  - OBJECT_IS_NULL
```
protected static final String OBJECT_IS_NULL
```
    See Also:
    
    Constant Field Values
  - NAME_IS_NULL
```
protected static final String NAME_IS_NULL
```
    See Also:
    
    Constant Field Values
  - VALUE_IS_NULL
```
protected static final String VALUE_IS_NULL
```
    See Also:
    
    Constant Field Values
  - ARRAY_IS_NULL
```
protected static final String ARRAY_IS_NULL
```
    See Also:
    
    Constant Field Values
- Method Detail
  - isObject
```
public boolean isObject()
```
    Detects whether this value represents a JSON object. If this is the case, this value is an instance of JsonObject.
    
    Returns:
    
    true if this value is an instance of JsonObject
  - isArray
```
public boolean isArray()
```
    Detects whether this value represents a JSON array. If this is the case, this value is an instance of JsonArray.
    
    Returns:
    
    true if this value is an instance of JsonArray
  - isNumber
```
public boolean isNumber()
```
    Detects whether this value represents a JSON number.
    
    Returns:
    
    true if this value represents a JSON number
  - isString
```
public boolean isString()
```
    Detects whether this value represents a JSON string.
    
    Returns:
    
    true if this value represents a JSON string
  - isBoolean
```
public boolean isBoolean()
```
    Detects whether this value represents a boolean value.
    
    Returns:
    
    true if this value represents either the JSON literal true or false
  - isTrue
```
public boolean isTrue()
```
    Detects whether this value represents the JSON literal true.
    
    Returns:
    
    true if this value represents the JSON literal true
  - isFalse
```
public boolean isFalse()
```
    Detects whether this value represents the JSON literal false.
    
    Returns:
    
    true if this value represents the JSON literal false
  - isNull
```
public boolean isNull()
```
    Detects whether this value represents the JSON literal null.
    
    Returns:
    
    true if this value represents the JSON literal null
  - asObject
```
public JsonObject asObject()
```
    Returns this JSON value as JsonObject, assuming that this value represents a JSON object. If this is not the case, an exception is thrown.
    
    Returns:
    
    a JSONObject for this value
    
    Throws:
    
    UnsupportedOperationException - if this value is not a JSON object
  - asArray
```
public JsonArray asArray()
```
    Returns this JSON value as JsonArray, assuming that this value represents a JSON array. If this is not the case, an exception is thrown.
    
    Returns:
    
    a JSONArray for this value
    
    Throws:
    
    UnsupportedOperationException - if this value is not a JSON array
  - asInt
```
public int asInt()
```
    Returns this JSON value as an int value, assuming that this value represents a JSON number that can be interpreted as Java int. If this is not the case, an exception is thrown.
    To be interpreted as Java int, the JSON number must neither contain an exponent nor a fraction part. Moreover, the number must be in the Integer range.
    
    Returns:
    
    this value as int
    
    Throws:
    
    UnsupportedOperationException - if this value is not a JSON number
    
    NumberFormatException - if this JSON number can not be interpreted as int value
  - asLong
```
public long asLong()
```
    Returns this JSON value as a long value, assuming that this value represents a JSON number that can be interpreted as Java long. If this is not the case, an exception is thrown.
    To be interpreted as Java long, the JSON number must neither contain an exponent nor a fraction part. Moreover, the number must be in the Long range.
    
    Returns:
    
    this value as long
    
    Throws:
    
    UnsupportedOperationException - if this value is not a JSON number
    
    NumberFormatException - if this JSON number can not be interpreted as long value
  - asFloat
```
public float asFloat()
```
    Returns this JSON value as a float value, assuming that this value represents a JSON number. If this is not the case, an exception is thrown.
    If the JSON number is out of the Float range, Float.POSITIVE_INFINITY or Float.NEGATIVE_INFINITY is returned.
    
    Returns:
    
    this value as float
    
    Throws:
    
    UnsupportedOperationException - if this value is not a JSON number
  - asDouble
```
public double asDouble()
```
    Returns this JSON value as a double value, assuming that this value represents a JSON number. If this is not the case, an exception is thrown.
    If the JSON number is out of the Double range, Double.POSITIVE_INFINITY or Double.NEGATIVE_INFINITY is returned.
    
    Returns:
    
    this value as double
    
    Throws:
    
    UnsupportedOperationException - if this value is not a JSON number
  - asString
```
public String asString()
```
    Returns this JSON value as String, assuming that this value represents a JSON string. If this is not the case, an exception is thrown.
    
    Returns:
    
    the string represented by this value
    
    Throws:
    
    UnsupportedOperationException - if this value is not a JSON string
  - asBoolean
```
public boolean asBoolean()
```
    Returns this JSON value as a boolean value, assuming that this value is either true or false. If this is not the case, an exception is thrown.
    
    Returns:
    
    this value as boolean
    
    Throws:
    
    UnsupportedOperationException - if this value is neither true or false
  - writeTo
```
public void writeTo(Writer writer)
             throws IOException
```
    Writes the JSON representation of this value to the given writer in its minimal form, without any additional whitespace.
    Writing performance can be improved by using a BufferedWriter.
    
    Parameters:
    
    writer - the writer to write this value to
    
    Throws:
    
    IOException - if an I/O error occurs in the writer
  - writeTo
```
public void writeTo(Writer writer,
                    WriterConfig config)
             throws IOException
```
    Writes the JSON representation of this value to the given writer using the given formatting.
    Writing performance can be improved by using a BufferedWriter.
    
    Parameters:
    
    writer - the writer to write this value to
    
    config - a configuration that controls the formatting or null for the minimal form
    
    Throws:
    
    IOException - if an I/O error occurs in the writer
  - toString
```
public String toString()
```
    Returns the JSON string for this value in its minimal form, without any additional whitespace. The result is guaranteed to be a valid input for the method Json.parse(String) and to create a value that is equal to this object.
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    a JSON string that represents this value
  - toString
```
public String toString(WriterConfig config)
```
    Returns the JSON string for this value using the given formatting.
    
    Parameters:
    
    config - a configuration that controls the formatting or null for the minimal form
    
    Returns:
    
    a JSON string that represents this value
  - equals
```
public boolean equals(Object object)
```
    Indicates whether some other object is "equal to" this one according to the contract specified in Object.equals(Object).
    Two JsonValues are considered equal if and only if they represent the same JSON text. As a consequence, two given JsonObjects may be different even though they contain the same set of names with the same values, but in a different order.
    
    Overrides:
    
    equals in class Object
    
    Parameters:
    
    object - the reference object with which to compare
    
    Returns:
    
    true if this object is the same as the object argument; false otherwise
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object

Class JsonValue

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

STRING_IS_NULL

OBJECT_IS_NULL

NAME_IS_NULL

VALUE_IS_NULL

ARRAY_IS_NULL

Method Detail

isObject

isArray

isNumber

isString

isBoolean

isTrue

isFalse

isNull

asObject

asArray

asInt

asLong

asFloat

asDouble

asString

asBoolean

writeTo

writeTo

toString

toString

equals

hashCode