java.lang.Object | |
↳ | com.fasterxml.jackson.core.JsonGenerator |
Known Direct Subclasses |
Known Indirect Subclasses |
Base class that defines public API for writing JSON content.
Instances are created using factory methods of
a JsonFactory
instance.
Nested Classes | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
JsonGenerator.Feature | Enumeration that defines all togglable features for generators. |
Fields | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|
_cfgPrettyPrinter | Object that handles pretty-printing (usually additional white space to make results more human-readable) during output. |
Protected Constructors | |||||||||||
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Public Methods | |||||||||||
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Method that can be used to verify that given schema can be used with
this generator (using
setSchema(FormatSchema) ). | |||||||||||
Method called to close this generator, so that no more content
can be written.
| |||||||||||
Method for enabling or disabling specified feature:
check
JsonGenerator.Feature for list of available features. | |||||||||||
Method for copying contents of the current event that
the given parser instance points to.
| |||||||||||
Method for copying contents of the current event
and following events that it encloses
the given parser instance points to.
| |||||||||||
Method for disabling specified features
(check
JsonGenerator.Feature for list of features) | |||||||||||
Method for enabling specified parser features:
check
JsonGenerator.Feature for list of available features. | |||||||||||
Method called to flush any buffered content to the underlying
target (output stream, writer), and to flush the target itself
as well.
| |||||||||||
Method for accessing custom escapes factory uses for
JsonGenerator s
it creates. | |||||||||||
Method for accessing the object used for writing Java
object as Json content
(using method
writeObject(Object) ). | |||||||||||
Accessor method for testing what is the highest unescaped character
configured for this generator.
| |||||||||||
Method that can be used to get access to object that is used
as target for generated output; this is usually either
OutputStream or Writer , depending on what
generator was constructed with. | |||||||||||
Method for accessing Schema that this parser uses, if any.
| |||||||||||
Method that can be called to determine whether this generator
is closed or not.
| |||||||||||
Method for checking whether given feature is enabled.
| |||||||||||
Method for defining custom escapes factory uses for
JsonGenerator s
it creates. | |||||||||||
Method that can be called to set or reset the object to
use for writing Java objects as JsonContent
(using method
writeObject(Object) ). | |||||||||||
Method that can be called to request that generator escapes
all character codes above specified code point (if positive value);
or, to not escape any characters except for ones that must be
escaped for the data format (if -1).
| |||||||||||
Method for setting a custom pretty printer, which is usually
used to add indentation for improved human readability.
| |||||||||||
Method to call to make this generator use specified schema.
| |||||||||||
Convenience method for enabling pretty-printing using
the default pretty printer
(
DefaultPrettyPrinter ). | |||||||||||
Accessor for finding out version of the bundle that provided this generator instance.
| |||||||||||
Convenience method for outputting a field entry ("member")
(that will contain a JSON Array value), and the START_ARRAY marker.
| |||||||||||
Method similar to
writeBinary(Base64Variant, byte[], int, int) ,
but where input is provided through a stream, allowing for incremental
writes without holding the whole input in memory. | |||||||||||
Similar to
writeBinary(Base64Variant, byte[], int, int) ,
but default to using the Jackson default Base64 variant
(which is MIME_NO_LINEFEEDS ). | |||||||||||
Similar to
writeBinary(Base64Variant, byte[], int, int) ,
but assumes default to using the Jackson default Base64 variant
(which is MIME_NO_LINEFEEDS ). | |||||||||||
Method that will output given chunk of binary data as base64
encoded, as a complete String value (surrounded by double quotes).
| |||||||||||
Similar to
writeBinary(Base64Variant, InputStream, int) ,
but assumes default to using the Jackson default Base64 variant
(which is MIME_NO_LINEFEEDS ). | |||||||||||
Convenience method for outputting a field entry ("member")
that contains specified data in base64-encoded form.
| |||||||||||
Method for outputting literal Json boolean value (one of
Strings 'true' and 'false').
| |||||||||||
Convenience method for outputting a field entry ("member")
that has a boolean value.
| |||||||||||
Method for writing closing marker of a JSON Array value
(character ']'; plus possible white space decoration
if pretty-printing is enabled).
| |||||||||||
Method for writing closing marker of a JSON Object value
(character '}'; plus possible white space decoration
if pretty-printing is enabled).
| |||||||||||
Method for writing a field name (JSON String surrounded by
double quotes: syntactically identical to a JSON String value),
possibly decorated by white space if pretty-printing is enabled.
| |||||||||||
Method similar to
writeFieldName(String) , main difference
being that it may perform better as some of processing (such as
quoting of certain characters, or encoding into external encoding
if supported by generator) can be done just once and reused for
later calls. | |||||||||||
Method for outputting literal Json null value.
| |||||||||||
Convenience method for outputting a field entry ("member")
that has JSON literal value null.
| |||||||||||
Method for outputting given value as Json number.
| |||||||||||
Method for outputting given value as Json number.
| |||||||||||
Write method that can be used for custom numeric types that can
not be (easily?) converted to "standard" Java number types.
| |||||||||||
Method for outputting indicate Json numeric value.
| |||||||||||
Method for outputting indicate Json numeric value.
| |||||||||||
Method for outputting given value as Json number.
| |||||||||||
Method for outputting indicate Json numeric value.
| |||||||||||
Convenience method for outputting a field entry ("member")
that has the specified numeric value.
| |||||||||||
Convenience method for outputting a field entry ("member")
that has the specified numeric value.
| |||||||||||
Convenience method for outputting a field entry ("member")
that has the specified numeric value.
| |||||||||||
Convenience method for outputting a field entry ("member")
that has the specified numeric value.
| |||||||||||
Convenience method for outputting a field entry ("member")
that has the specified numeric value.
| |||||||||||
Method for writing given Java object (POJO) as Json.
| |||||||||||
Convenience method for outputting a field entry ("member")
that has contents of specific Java object as its value.
| |||||||||||
Convenience method for outputting a field entry ("member")
(that will contain a JSON Object value), and the START_OBJECT marker.
| |||||||||||
Method that will force generator to copy
input text verbatim with no modifications (including
that no escaping is done and no separators are added even
if context [array, object] would otherwise require such).
| |||||||||||
Method that will force generator to copy
input text verbatim with no modifications (including
that no escaping is done and no separators are added even
if context [array, object] would otherwise require such).
| |||||||||||
Method that will force generator to copy
input text verbatim with no modifications (including
that no escaping is done and no separators are added even
if context [array, object] would otherwise require such).
| |||||||||||
Method that will force generator to copy
input text verbatim with no modifications (including
that no escaping is done and no separators are added even
if context [array, object] would otherwise require such).
| |||||||||||
Method similar to
writeString(String) but that takes as
its input a UTF-8 encoded String that is to be output as-is, without additional
escaping (type of which depends on data format; backslashes for JSON). | |||||||||||
Method that will force generator to copy
input text verbatim without any modifications, but assuming
it must constitute a single legal JSON value (number, string,
boolean, null, Array or List).
| |||||||||||
Method for writing starting marker of a JSON Array value
(character '['; plus possible white space decoration
if pretty-printing is enabled).
| |||||||||||
Method for writing starting marker of a JSON Object value
(character '{'; plus possible white space decoration
if pretty-printing is enabled).
| |||||||||||
Method for outputting a String value.
| |||||||||||
Method similar to
writeString(String) , but that takes
SerializableString which can make this potentially
more efficient to call as generator may be able to reuse
quoted and/or encoded representation. | |||||||||||
Method for outputting a String value.
| |||||||||||
Convenience method for outputting a field entry ("member")
that has a String value.
| |||||||||||
Method for writing given JSON tree (expressed as a tree
where given JsonNode is the root) using this generator.
| |||||||||||
Method similar to
writeString(String) but that takes as its input
a UTF-8 encoded String which has not been escaped using whatever
escaping scheme data format requires (for JSON that is backslash-escaping
for control characters and double-quotes; for other formats something else). |
[Expand]
Inherited Methods | |||||||||||
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From class
java.lang.Object
| |||||||||||
From interface
com.fasterxml.jackson.core.Versioned
| |||||||||||
From interface
java.io.Closeable
| |||||||||||
From interface
java.io.Flushable
| |||||||||||
From interface
java.lang.AutoCloseable
|
Object that handles pretty-printing (usually additional white space to make results more human-readable) during output. If null, no pretty-printing is done.
Method that can be used to verify that given schema can be used with
this generator (using setSchema(FormatSchema)
).
schema | Schema to check |
---|
Method called to close this generator, so that no more content can be written.
Whether the underlying target (stream, writer) gets closed depends
on whether this generator either manages the target (i.e. is the
only one with access to the target -- case if caller passes a
reference to the resource such as File, but not stream); or
has feature AUTO_CLOSE_TARGET
enabled.
If either of above is true, the target is also closed. Otherwise
(not managing, feature not enabled), target is not closed.
IOException |
---|
Method for enabling or disabling specified feature:
check JsonGenerator.Feature
for list of available features.
Method for copying contents of the current event that the given parser instance points to. Note that the method will not copy any other events, such as events contained within Json Array or Object structures.
Calling this method will not advance the given parser, although it may cause parser to internally process more data (if it lazy loads contents of value events, for example)
Method for copying contents of the current event and following events that it encloses the given parser instance points to.
So what constitutes enclosing? Here is the list of events that have associated enclosed events that will get copied:
START_OBJECT
:
all events up to and including matching (closing)
END_OBJECT
will be copied
START_ARRAY
all events up to and including matching (closing)
END_ARRAY
will be copied
FIELD_NAME
the logical value (which
can consist of a single scalar value; or a sequence of related
events for structured types (Json Arrays, Objects)) will
be copied along with the name itself. So essentially the
whole field entry (name and value) will be copied.
After calling this method, parser will point to the last event that was copied. This will either be the event parser already pointed to (if there were no enclosed events), or the last enclosed event copied.
Method for disabling specified features
(check JsonGenerator.Feature
for list of features)
Method for enabling specified parser features:
check JsonGenerator.Feature
for list of available features.
Method called to flush any buffered content to the underlying target (output stream, writer), and to flush the target itself as well.
IOException |
---|
Method for accessing custom escapes factory uses for JsonGenerator
s
it creates.
Method for accessing the object used for writing Java
object as Json content
(using method writeObject(Object)
).
Accessor method for testing what is the highest unescaped character configured for this generator. This may be either positive value (when escaping configuration has been set and is in effect), or 0 to indicate that no additional escaping is in effect. Some generators may not support additional escaping: for example, generators for binary formats that do not use escaping should simply return 0.
Method that can be used to get access to object that is used
as target for generated output; this is usually either
OutputStream
or Writer
, depending on what
generator was constructed with.
Note that returned value may be null in some cases; including
case where implementation does not want to exposed raw
source to caller.
In cases where output has been decorated, object returned here
is the decorated version; this allows some level of interaction
between users of generator and decorator object.
In general use of this accessor should be considered as "last effort", i.e. only used if no other mechanism is applicable.
Method for accessing Schema that this parser uses, if any. Default implementation returns null.
Method that can be called to determine whether this generator is closed or not. If it is closed, no more output can be done.
Method for checking whether given feature is enabled.
Check JsonGenerator.Feature
for list of available features.
Method for defining custom escapes factory uses for JsonGenerator
s
it creates.
Method that can be called to set or reset the object to
use for writing Java objects as JsonContent
(using method writeObject(Object)
).
Method that can be called to request that generator escapes all character codes above specified code point (if positive value); or, to not escape any characters except for ones that must be escaped for the data format (if -1). To force escaping of all non-ASCII characters, for example, this method would be called with value of 127.
Note that generators are NOT required to support setting of value higher than 127, because there are other ways to affect quoting (or lack thereof) of character codes between 0 and 127. Not all generators support concept of escaping, either; if so, calling this method will have no effect.
Default implementation does nothing; sub-classes need to redefine it according to rules of supported data format.
charCode | Either -1 to indicate that no additional escaping is to be done; or highest code point not to escape (meaning higher ones will be), if positive value. |
---|
Method for setting a custom pretty printer, which is usually used to add indentation for improved human readability. By default, generator does not do pretty printing.
To use the default pretty printer that comes with core
Jackson distribution, call useDefaultPrettyPrinter()
instead.
Method to call to make this generator use specified schema. Method must be called before generating any content, right after instance has been created. Note that not all generators support schemas; and those that do usually only accept specific types of schemas: ones defined for data format this generator produces.
If generator does not support specified schema, UnsupportedOperationException
is thrown.
schema | Schema to use |
---|
UnsupportedOperationException | if generator does not support schema |
---|
Convenience method for enabling pretty-printing using
the default pretty printer
(DefaultPrettyPrinter
).
Accessor for finding out version of the bundle that provided this generator instance.
Convenience method for outputting a field entry ("member") (that will contain a JSON Array value), and the START_ARRAY marker. Equivalent to:
writeFieldName(fieldName); writeStartArray();
Note: caller still has to take care to close the array (by calling {#link #writeEndArray}) after writing all values of the value Array.
Method similar to writeBinary(Base64Variant, byte[], int, int)
,
but where input is provided through a stream, allowing for incremental
writes without holding the whole input in memory.
b64variant | Base64 variant to use |
---|---|
data | InputStream to use for reading binary data to write. Will not be closed after successful write operation |
dataLength | (optional) number of bytes that will be available;
or -1 to be indicate it is not known.
If a positive length is given, data MUST provide at least
that many bytes: if not, an exception will be thrown.
Note that implementations
need not support cases where length is not known in advance; this
depends on underlying data format: JSON output does NOT require length,
other formats may. |
data
and written as binary payloadSimilar to writeBinary(Base64Variant, byte[], int, int)
,
but default to using the Jackson default Base64 variant
(which is MIME_NO_LINEFEEDS
).
Similar to writeBinary(Base64Variant, byte[], int, int)
,
but assumes default to using the Jackson default Base64 variant
(which is MIME_NO_LINEFEEDS
). Also
assumes that whole byte array is to be output.
Method that will output given chunk of binary data as base64 encoded, as a complete String value (surrounded by double quotes). This method defaults
Note: because Json Strings can not contain unescaped linefeeds,
if linefeeds are included (as per last argument), they must be
escaped. This adds overhead for decoding without improving
readability.
Alternatively if linefeeds are not included,
resulting String value may violate the requirement of base64
RFC which mandates line-length of 76 characters and use of
linefeeds. However, all JsonParser
implementations
are required to accept such "long line base64"; as do
typical production-level base64 decoders.
b64variant | Base64 variant to use: defines details such as whether padding is used (and if so, using which character); what is the maximum line length before adding linefeed, and also the underlying alphabet to use. |
---|
Similar to writeBinary(Base64Variant, InputStream, int)
,
but assumes default to using the Jackson default Base64 variant
(which is MIME_NO_LINEFEEDS
).
data | InputStream to use for reading binary data to write. Will not be closed after successful write operation |
---|---|
dataLength | (optional) number of bytes that will be available; or -1 to be indicate it is not known. Note that implementations need not support cases where length is not known in advance; this depends on underlying data format: JSON output does NOT require length, other formats may |
Convenience method for outputting a field entry ("member") that contains specified data in base64-encoded form. Equivalent to:
writeFieldName(fieldName); writeBinary(value);
Method for outputting literal Json boolean value (one of Strings 'true' and 'false'). Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
Convenience method for outputting a field entry ("member") that has a boolean value. Equivalent to:
writeFieldName(fieldName); writeBoolean(value);
Method for writing closing marker of a JSON Array value (character ']'; plus possible white space decoration if pretty-printing is enabled).
Marker can be written if the innermost structured type is Array.
Method for writing closing marker of a JSON Object value (character '}'; plus possible white space decoration if pretty-printing is enabled).
Marker can be written if the innermost structured type is Object, and the last written event was either a complete value, or START-OBJECT marker (see JSON specification for more details).
Method for writing a field name (JSON String surrounded by double quotes: syntactically identical to a JSON String value), possibly decorated by white space if pretty-printing is enabled.
Field names can only be written in Object context (check out JSON specification for details), when field name is expected (field names alternate with values).
Method similar to writeFieldName(String)
, main difference
being that it may perform better as some of processing (such as
quoting of certain characters, or encoding into external encoding
if supported by generator) can be done just once and reused for
later calls.
Default implementation simple uses unprocessed name container in serialized String; implementations are strongly encouraged to make use of more efficient methods argument object has.
Method for outputting literal Json null value. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
Convenience method for outputting a field entry ("member") that has JSON literal value null. Equivalent to:
writeFieldName(fieldName); writeNull();
Method for outputting given value as Json number. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
Method for outputting given value as Json number. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
Write method that can be used for custom numeric types that can
not be (easily?) converted to "standard" Java number types.
Because numbers are not surrounded by double quotes, regular
writeString(char[], int, int)
method can not be used; nor
writeRaw(char)
because that does not properly handle
value separators needed in Array or Object contexts.
Note: because of lack of type safety, some generator
implementations may not be able to implement this
method. For example, if a binary json format is used,
it may require type information for encoding; similarly
for generator-wrappers around Java objects or Json nodes.
If implementation does not implement this method,
it needs to throw UnsupportedOperationException
.
Method for outputting indicate Json numeric value. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
Method for outputting indicate Json numeric value. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
Method for outputting given value as Json number. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
Method for outputting indicate Json numeric value. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:
writeFieldName(fieldName); writeNumber(value);
Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:
writeFieldName(fieldName); writeNumber(value);
Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:
writeFieldName(fieldName); writeNumber(value);
Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:
writeFieldName(fieldName); writeNumber(value);
Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:
writeFieldName(fieldName); writeNumber(value);
Method for writing given Java object (POJO) as Json. Exactly how the object gets written depends on object in question (ad on codec, its configuration); for most beans it will result in Json object, but for others Json array, or String or numeric value (and for nulls, Json null literal. NOTE: generator must have its object codec set to non-null value; for generators created by a mapping factory this is the case, for others not.
Convenience method for outputting a field entry ("member") that has contents of specific Java object as its value. Equivalent to:
writeFieldName(fieldName); writeObject(pojo);
Convenience method for outputting a field entry ("member") (that will contain a JSON Object value), and the START_OBJECT marker. Equivalent to:
writeFieldName(fieldName); writeStartObject();
Note: caller still has to take care to close the Object (by calling {#link #writeEndObject}) after writing all entries of the value Object.
Method that will force generator to copy
input text verbatim with no modifications (including
that no escaping is done and no separators are added even
if context [array, object] would otherwise require such).
If such separators are desired, use
writeRawValue(String)
instead.
Note that not all generator implementations necessarily support
such by-pass methods: those that do not will throw
UnsupportedOperationException
.
Method that will force generator to copy
input text verbatim with no modifications (including
that no escaping is done and no separators are added even
if context [array, object] would otherwise require such).
If such separators are desired, use
writeRawValue(String)
instead.
Note that not all generator implementations necessarily support
such by-pass methods: those that do not will throw
UnsupportedOperationException
.
Method that will force generator to copy
input text verbatim with no modifications (including
that no escaping is done and no separators are added even
if context [array, object] would otherwise require such).
If such separators are desired, use
writeRawValue(String)
instead.
Note that not all generator implementations necessarily support
such by-pass methods: those that do not will throw
UnsupportedOperationException
.
Method that will force generator to copy
input text verbatim with no modifications (including
that no escaping is done and no separators are added even
if context [array, object] would otherwise require such).
If such separators are desired, use
writeRawValue(String)
instead.
Note that not all generator implementations necessarily support
such by-pass methods: those that do not will throw
UnsupportedOperationException
.
Method similar to writeString(String)
but that takes as
its input a UTF-8 encoded String that is to be output as-is, without additional
escaping (type of which depends on data format; backslashes for JSON).
However, quoting that data format requires (like double-quotes for JSON) will be added
around the value if and as necessary.
Note that some backends may choose not to support this method: for
example, if underlying destination is a Writer
using this method would require UTF-8 decoding.
If so, implementation may instead choose to throw a
UnsupportedOperationException
due to ineffectiveness
of having to decode input.
Method that will force generator to copy input text verbatim without any modifications, but assuming it must constitute a single legal JSON value (number, string, boolean, null, Array or List). Assuming this, proper separators are added if and as needed (comma or colon), and generator state updated to reflect this.
Method for writing starting marker of a JSON Array value (character '['; plus possible white space decoration if pretty-printing is enabled).
Array values can be written in any context where values are allowed: meaning everywhere except for when a field name is expected.
Method for writing starting marker of a JSON Object value (character '{'; plus possible white space decoration if pretty-printing is enabled).
Object values can be written in any context where values are allowed: meaning everywhere except for when a field name is expected.
Method for outputting a String value. Depending on context this means either array element, (object) field value or a stand alone String; but in all cases, String will be surrounded in double quotes, and contents will be properly escaped as required by JSON specification.
Method similar to writeString(String)
, but that takes
SerializableString
which can make this potentially
more efficient to call as generator may be able to reuse
quoted and/or encoded representation.
Default implementation just calls writeString(String)
;
sub-classes should override it with more efficient implementation
if possible.
Method for outputting a String value. Depending on context this means either array element, (object) field value or a stand alone String; but in all cases, String will be surrounded in double quotes, and contents will be properly escaped as required by JSON specification.
Convenience method for outputting a field entry ("member") that has a String value. Equivalent to:
writeFieldName(fieldName); writeString(value);
Note: many performance-sensitive implementations override this method
Method for writing given JSON tree (expressed as a tree
where given JsonNode is the root) using this generator.
This will generally just call
writeObject(Object)
with given node, but is added
for convenience and to make code more explicit in cases
where it deals specifically with trees.
Method similar to writeString(String)
but that takes as its input
a UTF-8 encoded String which has not been escaped using whatever
escaping scheme data format requires (for JSON that is backslash-escaping
for control characters and double-quotes; for other formats something else).
This means that textual JSON backends need to check if value needs
JSON escaping, but otherwise can just be copied as is to output.
Also, quoting that data format requires (like double-quotes for JSON) will be added
around the value if and as necessary.
Note that some backends may choose not to support this method: for
example, if underlying destination is a Writer
using this method would require UTF-8 decoding.
In this case
generator implementation may instead choose to throw a
UnsupportedOperationException
due to ineffectiveness
of having to decode input.