com.fasterxml.jackson.core

Class JsonGenerator

java.lang.Object

com.fasterxml.jackson.core.JsonGenerator

All Implemented Interfaces:

Versioned, Closeable, Flushable, AutoCloseable

Direct Known Subclasses:

GeneratorBase, JsonGeneratorDelegate

public abstract class JsonGenerator
extends Object
implements Closeable, Flushable, Versioned

Base class that defines public API for writing JSON content. Instances are created using factory methods of a JsonFactory instance.

Author:

Tatu Saloranta

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	JsonGenerator.Feature Enumeration that defines all togglable features for generators.

Field Summary

Fields

Modifier and Type	Field and Description
protected PrettyPrinter	_cfgPrettyPrinter Object that handles pretty-printing (usually additional white space to make results more human-readable) during output.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	JsonGenerator()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	_reportError(String msg) Helper method used for constructing and throwing JsonGenerationException with given base message.
protected void	_reportUnsupportedOperation()
protected void	_throwInternal()
protected void	_writeSimpleObject(Object value) Helper method to try to call appropriate write method for given untyped Object.
boolean	canOmitFields() Introspection method to call to check whether it is ok to omit writing of Object fields or not.
boolean	canUseSchema(FormatSchema schema) Method that can be used to verify that given schema can be used with this generator (using setSchema(com.fasterxml.jackson.core.FormatSchema)).
boolean	canWriteBinaryNatively() Introspection method that may be called to see if the underlying data format supports "native" binary data; that is, an efficient output of binary content without encoding.
boolean	canWriteObjectId() Introspection method that may be called to see if the underlying data format supports some kind of Object Ids natively (many do not; for example, JSON doesn't).
boolean	canWriteTypeId() Introspection method that may be called to see if the underlying data format supports some kind of Type Ids natively (many do not; for example, JSON doesn't).
abstract void	close() Method called to close this generator, so that no more content can be written.
JsonGenerator	configure(JsonGenerator.Feature f, boolean state) Method for enabling or disabling specified feature: check JsonGenerator.Feature for list of available features.
void	copyCurrentEvent(JsonParser jp) Method for copying contents of the current event that the given parser instance points to.
void	copyCurrentStructure(JsonParser jp) Method for copying contents of the current event and following events that it encloses the given parser instance points to.
abstract JsonGenerator	disable(JsonGenerator.Feature f) Method for disabling specified features (check JsonGenerator.Feature for list of features)
abstract JsonGenerator	enable(JsonGenerator.Feature f) Method for enabling specified parser features: check JsonGenerator.Feature for list of available features.
abstract void	flush() Method called to flush any buffered content to the underlying target (output stream, writer), and to flush the target itself as well.
CharacterEscapes	getCharacterEscapes() Method for accessing custom escapes factory uses for JsonGenerators it creates.
abstract ObjectCodec	getCodec() Method for accessing the object used for writing Java object as Json content (using method writeObject(java.lang.Object)).
abstract int	getFeatureMask() Bulk access method for getting state of all standard JsonGenerator.Features.
int	getHighestEscapedChar() Accessor method for testing what is the highest unescaped character configured for this generator.
abstract JsonStreamContext	getOutputContext()
Object	getOutputTarget() 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.
PrettyPrinter	getPrettyPrinter() Accessor for checking whether this generator has a configured PrettyPrinter; returns it if so, null if none configured.
FormatSchema	getSchema() Method for accessing Schema that this parser uses, if any.
abstract boolean	isClosed() Method that can be called to determine whether this generator is closed or not.
abstract boolean	isEnabled(JsonGenerator.Feature f) Method for checking whether given feature is enabled.
JsonGenerator	setCharacterEscapes(CharacterEscapes esc) Method for defining custom escapes factory uses for JsonGenerators it creates.
abstract JsonGenerator	setCodec(ObjectCodec oc) Method that can be called to set or reset the object to use for writing Java objects as JsonContent (using method writeObject(java.lang.Object)).
abstract JsonGenerator	setFeatureMask(int mask) Bulk set method for (re)settting states of all standard JsonGenerator.Features
JsonGenerator	setHighestNonEscapedChar(int charCode) 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).
JsonGenerator	setPrettyPrinter(PrettyPrinter pp) Method for setting a custom pretty printer, which is usually used to add indentation for improved human readability.
JsonGenerator	setRootValueSeparator(SerializableString sep) Method that allows overriding String used for separating root-level JSON values (default is single space character)
void	setSchema(FormatSchema schema) Method to call to make this generator use specified schema.
abstract JsonGenerator	useDefaultPrettyPrinter() Convenience method for enabling pretty-printing using the default pretty printer (DefaultPrettyPrinter).
abstract Version	version() Accessor for finding out version of the bundle that provided this generator instance.
void	writeArrayFieldStart(String fieldName) Convenience method for outputting a field entry ("member") (that will contain a JSON Array value), and the START_ARRAY marker.
abstract void	writeBinary(Base64Variant bv, byte[] data, int offset, int len) Method that will output given chunk of binary data as base64 encoded, as a complete String value (surrounded by double quotes).
abstract int	writeBinary(Base64Variant bv, InputStream data, int dataLength) 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.
void	writeBinary(byte[] data) Similar to writeBinary(Base64Variant,byte[],int,int), but assumes default to using the Jackson default Base64 variant (which is Base64Variants.MIME_NO_LINEFEEDS).
void	writeBinary(byte[] data, int offset, int len) Similar to writeBinary(Base64Variant,byte[],int,int), but default to using the Jackson default Base64 variant (which is Base64Variants.MIME_NO_LINEFEEDS).
int	writeBinary(InputStream data, int dataLength) Similar to writeBinary(Base64Variant,InputStream,int), but assumes default to using the Jackson default Base64 variant (which is Base64Variants.MIME_NO_LINEFEEDS).
void	writeBinaryField(String fieldName, byte[] data) Convenience method for outputting a field entry ("member") that contains specified data in base64-encoded form.
abstract void	writeBoolean(boolean state) Method for outputting literal Json boolean value (one of Strings 'true' and 'false').
void	writeBooleanField(String fieldName, boolean value) Convenience method for outputting a field entry ("member") that has a boolean value.
abstract void	writeEndArray() Method for writing closing marker of a JSON Array value (character ']'; plus possible white space decoration if pretty-printing is enabled).
abstract void	writeEndObject() Method for writing closing marker of a JSON Object value (character '}'; plus possible white space decoration if pretty-printing is enabled).
abstract void	writeFieldName(SerializableString name) 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.
abstract void	writeFieldName(String name) 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.
abstract void	writeNull() Method for outputting literal Json null value.
void	writeNullField(String fieldName) Convenience method for outputting a field entry ("member") that has JSON literal value null.
abstract void	writeNumber(BigDecimal dec) Method for outputting indicate Json numeric value.
abstract void	writeNumber(BigInteger v) Method for outputting given value as Json number.
abstract void	writeNumber(double d) Method for outputting indicate Json numeric value.
abstract void	writeNumber(float f) Method for outputting indicate Json numeric value.
abstract void	writeNumber(int v) Method for outputting given value as Json number.
abstract void	writeNumber(long v) Method for outputting given value as Json number.
void	writeNumber(short v) Method for outputting given value as Json number.
abstract void	writeNumber(String encodedValue) Write method that can be used for custom numeric types that can not be (easily?) converted to "standard" Java number types.
void	writeNumberField(String fieldName, BigDecimal value) Convenience method for outputting a field entry ("member") that has the specified numeric value.
void	writeNumberField(String fieldName, double value) Convenience method for outputting a field entry ("member") that has the specified numeric value.
void	writeNumberField(String fieldName, float value) Convenience method for outputting a field entry ("member") that has the specified numeric value.
void	writeNumberField(String fieldName, int value) Convenience method for outputting a field entry ("member") that has the specified numeric value.
void	writeNumberField(String fieldName, long value) Convenience method for outputting a field entry ("member") that has the specified numeric value.
abstract void	writeObject(Object pojo) Method for writing given Java object (POJO) as Json.
void	writeObjectField(String fieldName, Object pojo) Convenience method for outputting a field entry ("member") that has contents of specific Java object as its value.
void	writeObjectFieldStart(String fieldName) Convenience method for outputting a field entry ("member") (that will contain a JSON Object value), and the START_OBJECT marker.
void	writeObjectId(Object id) Method that can be called to output so-called native Object Id.
void	writeObjectRef(Object id) Method that can be called to output references to native Object Ids.
void	writeOmittedField(String fieldName) Method called to indicate that a property in this position was skipped.
abstract void	writeRaw(char c) 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).
abstract void	writeRaw(char[] text, int offset, int len) 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).
void	writeRaw(SerializableString raw) 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).
abstract void	writeRaw(String text) 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).
abstract void	writeRaw(String text, int offset, int len) 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).
abstract void	writeRawUTF8String(byte[] text, int offset, int length) 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).
abstract void	writeRawValue(char[] text, int offset, int len)
abstract void	writeRawValue(String text) 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).
abstract void	writeRawValue(String text, int offset, int len)
abstract void	writeStartArray() Method for writing starting marker of a Array value (for JSON this is character '['; plus possible white space decoration if pretty-printing is enabled).
void	writeStartArray(int size) Method for writing start marker of an Array value, similar to writeStartArray(), but also specifying how many elements will be written for the array before calling writeEndArray().
abstract void	writeStartObject() Method for writing starting marker of a JSON Object value (character '{'; plus possible white space decoration if pretty-printing is enabled).
abstract void	writeString(char[] text, int offset, int len) Method for outputting a String value.
abstract void	writeString(SerializableString text) 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.
abstract void	writeString(String text) Method for outputting a String value.
void	writeStringField(String fieldName, String value) Convenience method for outputting a field entry ("member") that has a String value.
abstract void	writeTree(TreeNode rootNode) Method for writing given JSON tree (expressed as a tree where given JsonNode is the root) using this generator.
void	writeTypeId(Object id) Method that can be called to output so-called native Type Id.
abstract void	writeUTF8String(byte[] text, int offset, int length) 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).

Methods inherited from class java.lang.Object

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

Field Detail

_cfgPrettyPrinter

protected PrettyPrinter _cfgPrettyPrinter

Object that handles pretty-printing (usually additional white space to make results more human-readable) during output. If null, no pretty-printing is done.

Constructor Detail

JsonGenerator

protected JsonGenerator()

Method Detail

setCodec

public abstract JsonGenerator setCodec(ObjectCodec oc)

Method that can be called to set or reset the object to use for writing Java objects as JsonContent (using method writeObject(java.lang.Object)).

Returns:

Generator itself (this), to allow chaining

getCodec

public abstract ObjectCodec getCodec()

Method for accessing the object used for writing Java object as Json content (using method writeObject(java.lang.Object)).

version

public abstract Version version()

Accessor for finding out version of the bundle that provided this generator instance.

Specified by:

version in interface Versioned

getOutputTarget

public Object getOutputTarget()

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.

enable

public abstract JsonGenerator enable(JsonGenerator.Feature f)

Method for enabling specified parser features: check JsonGenerator.Feature for list of available features.

Returns:

Generator itself (this), to allow chaining

disable

public abstract JsonGenerator disable(JsonGenerator.Feature f)

Method for disabling specified features (check JsonGenerator.Feature for list of features)

Returns:

Generator itself (this), to allow chaining

configure

public final JsonGenerator configure(JsonGenerator.Feature f,
                      boolean state)

Method for enabling or disabling specified feature: check JsonGenerator.Feature for list of available features.

Returns:

Generator itself (this), to allow chaining

isEnabled

public abstract boolean isEnabled(JsonGenerator.Feature f)

Method for checking whether given feature is enabled. Check JsonGenerator.Feature for list of available features.

getFeatureMask

public abstract int getFeatureMask()

Bulk access method for getting state of all standard JsonGenerator.Features.

Returns:

Bit mask that defines current states of all standard JsonGenerator.Features.

Since:

2.3

setFeatureMask

public abstract JsonGenerator setFeatureMask(int mask)

Bulk set method for (re)settting states of all standard JsonGenerator.Features

Returns:

This parser object, to allow chaining of calls

Since:

2.3

setSchema

public void setSchema(FormatSchema schema)

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.

Parameters:

schema - Schema to use

Throws:

UnsupportedOperationException - if generator does not support schema

getSchema

public FormatSchema getSchema()

Method for accessing Schema that this parser uses, if any. Default implementation returns null.

Since:

2.1

setPrettyPrinter

public JsonGenerator setPrettyPrinter(PrettyPrinter pp)

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.

Returns:

Generator itself (this), to allow chaining

getPrettyPrinter

public PrettyPrinter getPrettyPrinter()

Accessor for checking whether this generator has a configured PrettyPrinter; returns it if so, null if none configured.

Since:

2.1

useDefaultPrettyPrinter

public abstract JsonGenerator useDefaultPrettyPrinter()

Convenience method for enabling pretty-printing using the default pretty printer (DefaultPrettyPrinter).

Returns:

Generator itself (this), to allow chaining

setHighestNonEscapedChar

public JsonGenerator setHighestNonEscapedChar(int charCode)

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.

Parameters:

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.

getHighestEscapedChar

public int getHighestEscapedChar()

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.

Returns:

Currently active limitation for highest non-escaped character, if defined; or -1 to indicate no additional escaping is performed.

getCharacterEscapes

public CharacterEscapes getCharacterEscapes()

Method for accessing custom escapes factory uses for JsonGenerators it creates.

setCharacterEscapes

public JsonGenerator setCharacterEscapes(CharacterEscapes esc)

Method for defining custom escapes factory uses for JsonGenerators it creates.

Default implementation does nothing and simply returns this instance.

setRootValueSeparator

public JsonGenerator setRootValueSeparator(SerializableString sep)

Method that allows overriding String used for separating root-level JSON values (default is single space character)

Default implementation throws UnsupportedOperationException.

Parameters:

sep - Separator to use, if any; null means that no separator is automatically added

Since:

2.1

canUseSchema

public boolean canUseSchema(FormatSchema schema)

Method that can be used to verify that given schema can be used with this generator (using setSchema(com.fasterxml.jackson.core.FormatSchema)).

Parameters:

schema - Schema to check

Returns:

True if this generator can use given schema; false if not

canWriteObjectId

public boolean canWriteObjectId()

Introspection method that may be called to see if the underlying data format supports some kind of Object Ids natively (many do not; for example, JSON doesn't). This method must be called prior to calling writeObjectId(java.lang.Object) or writeObjectRef(java.lang.Object).

Default implementation returns false; overridden by data formats that do support native Object Ids. Caller is expected to either use a non-native notation (explicit property or such), or fail, in case it can not use native object ids.

Since:

2.3

canWriteTypeId

public boolean canWriteTypeId()

Introspection method that may be called to see if the underlying data format supports some kind of Type Ids natively (many do not; for example, JSON doesn't). This method must be called prior to calling writeTypeId(java.lang.Object).

Default implementation returns false; overridden by data formats that do support native Type Ids. Caller is expected to either use a non-native notation (explicit property or such), or fail, in case it can not use native type ids.

Since:

2.3

canWriteBinaryNatively

public boolean canWriteBinaryNatively()

Introspection method that may be called to see if the underlying data format supports "native" binary data; that is, an efficient output of binary content without encoding.

Default implementation returns false; overridden by data formats that do support native binary content.

Since:

2.3

canOmitFields

public boolean canOmitFields()

Introspection method to call to check whether it is ok to omit writing of Object fields or not. Most formats do allow omission, but certain positional formats (such as CSV) require output of placeholders, even if no real values are to be emitted.

Since:

2.3

writeStartArray

public abstract void writeStartArray()
                              throws IOException

Method for writing starting marker of a Array value (for JSON this is 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.

Throws:

IOException

writeStartArray

public void writeStartArray(int size)
                     throws IOException

Method for writing start marker of an Array value, similar to writeStartArray(), but also specifying how many elements will be written for the array before calling writeEndArray().

Default implementation simply calls writeStartArray().

Parameters:

size - Number of elements this array will have: actual number of values written (before matching call to writeEndArray() MUST match; generator MAY verify this is the case.

Throws:

IOException

writeEndArray

public abstract void writeEndArray()
                            throws IOException

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.

Throws:

IOException

writeStartObject

public abstract void writeStartObject()
                               throws IOException

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.

Throws:

IOException

writeEndObject

public abstract void writeEndObject()
                             throws IOException

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).

Throws:

IOException

writeFieldName

public abstract void writeFieldName(String name)
                             throws IOException

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).

Throws:

IOException

writeFieldName

public abstract void writeFieldName(SerializableString name)
                             throws IOException

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.

Throws:

IOException

writeString

public abstract void writeString(String text)
                          throws IOException

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.

Throws:

IOException

writeString

public abstract void writeString(char[] text,
               int offset,
               int len)
                          throws IOException

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.

Throws:

IOException

writeString

public abstract void writeString(SerializableString text)
                          throws IOException

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.

Throws:

IOException

writeRawUTF8String

public abstract void writeRawUTF8String(byte[] text,
                      int offset,
                      int length)
                                 throws IOException

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.

Throws:

IOException

writeUTF8String

public abstract void writeUTF8String(byte[] text,
                   int offset,
                   int length)
                              throws IOException

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.

Throws:

IOException

writeRaw

public abstract void writeRaw(String text)
                       throws IOException

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.

Throws:

IOException

writeRaw

public abstract void writeRaw(String text,
            int offset,
            int len)
                       throws IOException

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.

Throws:

IOException

writeRaw

public abstract void writeRaw(char[] text,
            int offset,
            int len)
                       throws IOException

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.

Throws:

IOException

writeRaw

public abstract void writeRaw(char c)
                       throws IOException

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.

Throws:

IOException

writeRaw

public void writeRaw(SerializableString raw)
              throws IOException

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.

The default implementation delegates to writeRaw(String); other backends that support raw inclusion of text are encouraged to implement it in more efficient manner (especially if they use UTF-8 encoding).

Throws:

IOException

Since:

2.1

writeRawValue

public abstract void writeRawValue(String text)
                            throws IOException

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.

Throws:

IOException

writeRawValue

public abstract void writeRawValue(String text,
                 int offset,
                 int len)
                            throws IOException

Throws:

IOException

writeRawValue

public abstract void writeRawValue(char[] text,
                 int offset,
                 int len)
                            throws IOException

Throws:

IOException

writeBinary

public abstract void writeBinary(Base64Variant bv,
               byte[] data,
               int offset,
               int len)
                          throws IOException

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.

Parameters:

bv - 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.

Throws:

IOException

writeBinary

public void writeBinary(byte[] data,
               int offset,
               int len)
                 throws IOException

Similar to writeBinary(Base64Variant,byte[],int,int), but default to using the Jackson default Base64 variant (which is Base64Variants.MIME_NO_LINEFEEDS).

Throws:

IOException

writeBinary

public void writeBinary(byte[] data)
                 throws IOException

Similar to writeBinary(Base64Variant,byte[],int,int), but assumes default to using the Jackson default Base64 variant (which is Base64Variants.MIME_NO_LINEFEEDS). Also assumes that whole byte array is to be output.

Throws:

IOException

writeBinary

public int writeBinary(InputStream data,
              int dataLength)
                throws IOException

Similar to writeBinary(Base64Variant,InputStream,int), but assumes default to using the Jackson default Base64 variant (which is Base64Variants.MIME_NO_LINEFEEDS).

Parameters:

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

Throws:

IOException

writeBinary

public abstract int writeBinary(Base64Variant bv,
              InputStream data,
              int dataLength)
                         throws IOException

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.

Parameters:

bv - 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.

Returns:

Number of bytes read from data and written as binary payload

Throws:

IOException

Since:

2.1

writeNumber

public void writeNumber(short v)
                 throws IOException

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.

Throws:

IOException

Since:

2.2

writeNumber

public abstract void writeNumber(int v)
                          throws IOException

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.

Throws:

IOException

writeNumber

public abstract void writeNumber(long v)
                          throws IOException

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.

Throws:

IOException

writeNumber

public abstract void writeNumber(BigInteger v)
                          throws IOException

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.

Throws:

IOException

writeNumber

public abstract void writeNumber(double d)
                          throws IOException

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.

Throws:

IOException

writeNumber

public abstract void writeNumber(float f)
                          throws IOException

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.

Throws:

IOException

writeNumber

public abstract void writeNumber(BigDecimal dec)
                          throws IOException

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.

Throws:

IOException

writeNumber

public abstract void writeNumber(String encodedValue)
                          throws IOException

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(java.lang.String) method can not be used; nor writeRaw(java.lang.String) 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.

Throws:

UnsupportedOperationException - If underlying data format does not support numbers serialized textually AND if generator is not allowed to just output a String instead (Schema-based formats may require actual number, for example)

IOException

writeBoolean

public abstract void writeBoolean(boolean state)
                           throws IOException

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.

Throws:

IOException

writeNull

public abstract void writeNull()
                        throws IOException

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.

Throws:

IOException

writeObjectId

public void writeObjectId(Object id)
                   throws IOException

Method that can be called to output so-called native Object Id. Note that it may only be called after ensuring this is legal (with canWriteObjectId()), as not all data formats have native type id support; and some may only allow them in certain positions or locations. If output is not allowed by the data format in this position, a JsonGenerationException will be thrown.

Throws:

IOException

Since:

2.3

writeObjectRef

public void writeObjectRef(Object id)
                    throws IOException

Method that can be called to output references to native Object Ids. Note that it may only be called after ensuring this is legal (with canWriteObjectId()), as not all data formats have native type id support; and some may only allow them in certain positions or locations. If output is not allowed by the data format in this position, a JsonGenerationException will be thrown.

Throws:

IOException

writeTypeId

public void writeTypeId(Object id)
                 throws IOException

Method that can be called to output so-called native Type Id. Note that it may only be called after ensuring this is legal (with canWriteTypeId()), as not all data formats have native type id support; and some may only allow them in certain positions or locations. If output is not allowed by the data format in this position, a JsonGenerationException will be thrown.

Throws:

IOException

Since:

2.3

writeObject

public abstract void writeObject(Object pojo)
                          throws IOException

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.

Throws:

IOException

writeTree

public abstract void writeTree(TreeNode rootNode)
                        throws IOException

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(java.lang.Object) with given node, but is added for convenience and to make code more explicit in cases where it deals specifically with trees.

Throws:

IOException

writeStringField

public void writeStringField(String fieldName,
                    String value)
                      throws IOException

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

Throws:

IOException

writeBooleanField

public final void writeBooleanField(String fieldName,
                     boolean value)
                             throws IOException

Convenience method for outputting a field entry ("member") that has a boolean value. Equivalent to:

  writeFieldName(fieldName);
  writeBoolean(value);

Throws:

IOException

writeNullField

public final void writeNullField(String fieldName)
                          throws IOException

Convenience method for outputting a field entry ("member") that has JSON literal value null. Equivalent to:

  writeFieldName(fieldName);
  writeNull();

Throws:

IOException

writeNumberField

public final void writeNumberField(String fieldName,
                    int value)
                            throws IOException

Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:

  writeFieldName(fieldName);
  writeNumber(value);

Throws:

IOException

writeNumberField

public final void writeNumberField(String fieldName,
                    long value)
                            throws IOException

Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:

  writeFieldName(fieldName);
  writeNumber(value);

Throws:

IOException

writeNumberField

public final void writeNumberField(String fieldName,
                    double value)
                            throws IOException

Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:

  writeFieldName(fieldName);
  writeNumber(value);

Throws:

IOException

writeNumberField

public final void writeNumberField(String fieldName,
                    float value)
                            throws IOException

Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:

  writeFieldName(fieldName);
  writeNumber(value);

Throws:

IOException

writeNumberField

public final void writeNumberField(String fieldName,
                    BigDecimal value)
                            throws IOException

Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:

  writeFieldName(fieldName);
  writeNumber(value);

Throws:

IOException

writeBinaryField

public final void writeBinaryField(String fieldName,
                    byte[] data)
                            throws IOException

Convenience method for outputting a field entry ("member") that contains specified data in base64-encoded form. Equivalent to:

  writeFieldName(fieldName);
  writeBinary(value);

Throws:

IOException

writeArrayFieldStart

public final void writeArrayFieldStart(String fieldName)
                                throws IOException

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.

Throws:

IOException

writeObjectFieldStart

public final void writeObjectFieldStart(String fieldName)
                                 throws IOException

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.

Throws:

IOException

writeObjectField

public final void writeObjectField(String fieldName,
                    Object pojo)
                            throws IOException

Convenience method for outputting a field entry ("member") that has contents of specific Java object as its value. Equivalent to:

  writeFieldName(fieldName);
  writeObject(pojo);

Throws:

IOException

writeOmittedField

public void writeOmittedField(String fieldName)
                       throws IOException

Method called to indicate that a property in this position was skipped. It is usually only called for generators that return false from canOmitFields().

Default implementation does nothing.

Throws:

IOException

Since:

2.3

copyCurrentEvent

public void copyCurrentEvent(JsonParser jp)
                      throws IOException

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)

Throws:

IOException

copyCurrentStructure

public void copyCurrentStructure(JsonParser jp)
                          throws IOException

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:

• JsonToken.START_OBJECT: all events up to and including matching (closing) JsonToken.END_OBJECT will be copied
• JsonToken.START_ARRAY all events up to and including matching (closing) JsonToken.END_ARRAY will be copied
• JsonToken.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.

Throws:

IOException

getOutputContext

public abstract JsonStreamContext getOutputContext()

Returns:

Context object that can give information about logical position within generated json content.

flush

public abstract void flush()
                    throws IOException

Method called to flush any buffered content to the underlying target (output stream, writer), and to flush the target itself as well.

Specified by:

flush in interface Flushable

Throws:

IOException

isClosed

public abstract boolean isClosed()

Method that can be called to determine whether this generator is closed or not. If it is closed, no more output can be done.

close

public abstract void close()
                    throws IOException

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 JsonGenerator.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.

Specified by:

close in interface Closeable

Specified by:

close in interface AutoCloseable

Throws:

IOException

_reportError

protected void _reportError(String msg)
                     throws JsonGenerationException

Helper method used for constructing and throwing JsonGenerationException with given base message.

Note that sub-classes may override this method to add more detail or use a JsonGenerationException sub-class.

Throws:

JsonGenerationException

_throwInternal

protected final void _throwInternal()

_reportUnsupportedOperation

protected void _reportUnsupportedOperation()

_writeSimpleObject

protected void _writeSimpleObject(Object value)
                           throws IOException

Helper method to try to call appropriate write method for given untyped Object. At this point, no structural conversions should be done, only simple basic types are to be coerced as necessary.

Parameters:

value - Non-null value to write

Throws:

IOException