public class JsonObject extends JsonValue implements java.lang.Iterable<JsonObject.Member>
Members can be added using the add(String, ...)
methods which accept instances of
JsonValue
, strings, primitive numbers, and boolean values. To modify certain values of an
object, use the set(String, ...)
methods. Please note that the add
methods are faster than set
as they do not search for existing members. On the other
hand, the add
methods do not prevent adding multiple members with the same name, as
duplicate names are discouraged but not prohibited by JSON.
Members can be accessed by their name using get(String)
. A list of all names can be
obtained from the method names()
. This class also supports iterating over the members in
document order using an iterator()
or an enhanced for loop:
for( Member member : jsonObject ) { String name = member.getName(); JsonValue value = member.getValue(); ... }
Even though JSON objects are unordered by definition, instances of this class preserve the order of members to allow processing in document order and to guarantee a predictable output.
Note that this class is not thread-safe. If multiple threads access a
JsonObject
instance concurrently, while at least one of these threads modifies the
contents of this object, access to the instance must be synchronized externally. Failure to do so
may lead to an inconsistent state.
This class is not supposed to be extended by clients.
Modifier and Type | Class and Description |
---|---|
static class |
JsonObject.Member
Represents a member of a JSON object, i.e.
|
Constructor and Description |
---|
JsonObject()
Creates a new empty JsonObject.
|
JsonObject(JsonObject object)
Creates a new JsonObject, initialized with the contents of the specified JSON object.
|
Modifier and Type | Method and Description |
---|---|
JsonObject |
add(java.lang.String name,
boolean value)
Adds a new member at the end of this object, with the specified name and the JSON
representation of the specified
boolean value. |
JsonObject |
add(java.lang.String name,
double value)
Adds a new member at the end of this object, with the specified name and the JSON
representation of the specified
double value. |
JsonObject |
add(java.lang.String name,
float value)
Adds a new member at the end of this object, with the specified name and the JSON
representation of the specified
float value. |
JsonObject |
add(java.lang.String name,
int value)
Adds a new member at the end of this object, with the specified name and the JSON
representation of the specified
int value. |
JsonObject |
add(java.lang.String name,
JsonValue value)
Adds a new member at the end of this object, with the specified name and the specified JSON
value.
|
JsonObject |
add(java.lang.String name,
long value)
Adds a new member at the end of this object, with the specified name and the JSON
representation of the specified
long value. |
JsonObject |
add(java.lang.String name,
java.lang.String value)
Adds a new member at the end of this object, with the specified name and the JSON
representation of the specified string.
|
JsonObject |
asObject()
Returns this JSON value as
JsonObject , assuming that this value represents a JSON
object. |
boolean |
equals(java.lang.Object obj)
Indicates whether some other object is "equal to" this one according to the contract specified
in
Object.equals(Object) . |
JsonValue |
get(java.lang.String name)
Returns the value of the member with the specified name in this object.
|
int |
hashCode() |
boolean |
isEmpty()
Returns
true if this object contains no members. |
boolean |
isObject()
Detects whether this value represents a JSON object.
|
java.util.Iterator<JsonObject.Member> |
iterator()
Returns an iterator over the members of this object in document order.
|
java.util.List<java.lang.String> |
names()
Returns a list of the names in this object in document order.
|
static JsonObject |
readFrom(java.io.Reader reader)
Reads a JSON object from the given reader.
|
static JsonObject |
readFrom(java.lang.String string)
Reads a JSON object from the given string.
|
JsonObject |
remove(java.lang.String name)
Removes a member with the specified name from this object.
|
JsonObject |
set(java.lang.String name,
boolean value)
Sets the value of the member with the specified name to the JSON representation of the
specified
boolean value. |
JsonObject |
set(java.lang.String name,
double value)
Sets the value of the member with the specified name to the JSON representation of the
specified
double value. |
JsonObject |
set(java.lang.String name,
float value)
Sets the value of the member with the specified name to the JSON representation of the
specified
float value. |
JsonObject |
set(java.lang.String name,
int value)
Sets the value of the member with the specified name to the JSON representation of the
specified
int value. |
JsonObject |
set(java.lang.String name,
JsonValue value)
Sets the value of the member with the specified name to the specified JSON value.
|
JsonObject |
set(java.lang.String name,
long value)
Sets the value of the member with the specified name to the JSON representation of the
specified
long value. |
JsonObject |
set(java.lang.String name,
java.lang.String value)
Sets the value of the member with the specified name to the JSON representation of the
specified string.
|
int |
size()
Returns the number of members (i.e.
|
static JsonObject |
unmodifiableObject(JsonObject object)
Returns an unmodifiable JsonObject for the specified one.
|
protected void |
write(org.eclipse.rap.json.JsonWriter writer) |
public JsonObject()
public JsonObject(JsonObject object)
object
- the JSON object to get the initial contents from, must not be null
public static JsonObject readFrom(java.io.Reader reader) throws java.io.IOException
Characters are read in chunks and buffered internally, therefore wrapping an existing reader in
an additional BufferedReader
does not improve reading
performance.
reader
- the reader to read the JSON object fromjava.io.IOException
- if an I/O error occurs in the readerParseException
- if the input is not valid JSONjava.lang.UnsupportedOperationException
- if the input does not contain a JSON objectpublic static JsonObject readFrom(java.lang.String string)
string
- the string that contains the JSON objectParseException
- if the input is not valid JSONjava.lang.UnsupportedOperationException
- if the input does not contain a JSON objectpublic static JsonObject unmodifiableObject(JsonObject object)
The returned JsonObject is backed by the given object and reflect changes that happen to it.
Attempts to modify the returned JsonObject result in an
UnsupportedOperationException
.
object
- the JsonObject for which an unmodifiable JsonObject is to be returnedpublic JsonObject add(java.lang.String name, int value)
int
value.
This method does not prevent duplicate names. Adding a member with a name that
already exists in the object will add another member with the same name. In order to replace
existing members, use the method set(name, value)
instead. However,
add is much faster than set (because it does not need to search for
existing members). Therefore add should be preferred when constructing new objects.
name
- the name of the member to addvalue
- the value of the member to addpublic JsonObject add(java.lang.String name, long value)
long
value.
This method does not prevent duplicate names. Adding a member with a name that
already exists in the object will add another member with the same name. In order to replace
existing members, use the method set(name, value)
instead. However,
add is much faster than set (because it does not need to search for
existing members). Therefore add should be preferred when constructing new objects.
name
- the name of the member to addvalue
- the value of the member to addpublic JsonObject add(java.lang.String name, float value)
float
value.
This method does not prevent duplicate names. Adding a member with a name that
already exists in the object will add another member with the same name. In order to replace
existing members, use the method set(name, value)
instead. However,
add is much faster than set (because it does not need to search for
existing members). Therefore add should be preferred when constructing new objects.
name
- the name of the member to addvalue
- the value of the member to addpublic JsonObject add(java.lang.String name, double value)
double
value.
This method does not prevent duplicate names. Adding a member with a name that
already exists in the object will add another member with the same name. In order to replace
existing members, use the method set(name, value)
instead. However,
add is much faster than set (because it does not need to search for
existing members). Therefore add should be preferred when constructing new objects.
name
- the name of the member to addvalue
- the value of the member to addpublic JsonObject add(java.lang.String name, boolean value)
boolean
value.
This method does not prevent duplicate names. Adding a member with a name that
already exists in the object will add another member with the same name. In order to replace
existing members, use the method set(name, value)
instead. However,
add is much faster than set (because it does not need to search for
existing members). Therefore add should be preferred when constructing new objects.
name
- the name of the member to addvalue
- the value of the member to addpublic JsonObject add(java.lang.String name, java.lang.String value)
This method does not prevent duplicate names. Adding a member with a name that
already exists in the object will add another member with the same name. In order to replace
existing members, use the method set(name, value)
instead. However,
add is much faster than set (because it does not need to search for
existing members). Therefore add should be preferred when constructing new objects.
name
- the name of the member to addvalue
- the value of the member to addpublic JsonObject add(java.lang.String name, JsonValue value)
This method does not prevent duplicate names. Adding a member with a name that
already exists in the object will add another member with the same name. In order to replace
existing members, use the method set(name, value)
instead. However,
add is much faster than set (because it does not need to search for
existing members). Therefore add should be preferred when constructing new objects.
name
- the name of the member to addvalue
- the value of the member to add, must not be null
public JsonObject set(java.lang.String name, int value)
int
value. If this object does not contain a member with this name, a
new member is added at the end of the object. If this object contains multiple members with
this name, only the last one is changed.
This method should only be used to modify existing objects. To fill a new
object with members, the method add(name, value)
should be preferred which is much
faster (as it does not need to search for existing members).
name
- the name of the member to replacevalue
- the value to set to the memberpublic JsonObject set(java.lang.String name, long value)
long
value. If this object does not contain a member with this name, a
new member is added at the end of the object. If this object contains multiple members with
this name, only the last one is changed.
This method should only be used to modify existing objects. To fill a new
object with members, the method add(name, value)
should be preferred which is much
faster (as it does not need to search for existing members).
name
- the name of the member to replacevalue
- the value to set to the memberpublic JsonObject set(java.lang.String name, float value)
float
value. If this object does not contain a member with this name, a
new member is added at the end of the object. If this object contains multiple members with
this name, only the last one is changed.
This method should only be used to modify existing objects. To fill a new
object with members, the method add(name, value)
should be preferred which is much
faster (as it does not need to search for existing members).
name
- the name of the member to addvalue
- the value of the member to addpublic JsonObject set(java.lang.String name, double value)
double
value. If this object does not contain a member with this name, a
new member is added at the end of the object. If this object contains multiple members with
this name, only the last one is changed.
This method should only be used to modify existing objects. To fill a new
object with members, the method add(name, value)
should be preferred which is much
faster (as it does not need to search for existing members).
name
- the name of the member to addvalue
- the value of the member to addpublic JsonObject set(java.lang.String name, boolean value)
boolean
value. If this object does not contain a member with this name,
a new member is added at the end of the object. If this object contains multiple members with
this name, only the last one is changed.
This method should only be used to modify existing objects. To fill a new
object with members, the method add(name, value)
should be preferred which is much
faster (as it does not need to search for existing members).
name
- the name of the member to addvalue
- the value of the member to addpublic JsonObject set(java.lang.String name, java.lang.String value)
This method should only be used to modify existing objects. To fill a new
object with members, the method add(name, value)
should be preferred which is much
faster (as it does not need to search for existing members).
name
- the name of the member to addvalue
- the value of the member to addpublic JsonObject set(java.lang.String name, JsonValue value)
This method should only be used to modify existing objects. To fill a new
object with members, the method add(name, value)
should be preferred which is much
faster (as it does not need to search for existing members).
name
- the name of the member to addvalue
- the value of the member to add, must not be null
public JsonObject remove(java.lang.String name)
name
- the name of the member to removepublic JsonValue get(java.lang.String name)
name
- the name of the member whose value is to be returnednull
if this
object does not contain a member with that namepublic int size()
public boolean isEmpty()
true
if this object contains no members.true
if this object contains no memberspublic java.util.List<java.lang.String> names()
public java.util.Iterator<JsonObject.Member> iterator()
iterator
in interface java.lang.Iterable<JsonObject.Member>
protected void write(org.eclipse.rap.json.JsonWriter writer) throws java.io.IOException
public boolean isObject()
JsonValue
JsonObject
.public JsonObject asObject()
JsonValue
JsonObject
, assuming that this value represents a JSON
object. If this is not the case, an exception is thrown.public boolean equals(java.lang.Object obj)
JsonValue
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.
Copyright (c) EclipseSource and others 2002, 2017.
All rights reserved. This program and the accompanying materials
are made available under the terms of the
Eclipse Public License v1.0