Class JsonParser
- java.lang.Object
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- com.fasterxml.jackson.core.JsonParser
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- All Implemented Interfaces:
Versioned
,Closeable
,AutoCloseable
- Direct Known Subclasses:
JsonParserDelegate
,ParserMinimalBase
public abstract class JsonParser extends Object implements Closeable, Versioned
Base class that defines public API for reading JSON content. Instances are created using factory methods of aJsonFactory
instance.
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Nested Class Summary
Nested Classes Modifier and Type Class Description static class
JsonParser.Feature
Enumeration that defines all on/off features for parsers.static class
JsonParser.NumberType
Enumeration of possible "native" (optimal) types that can be used for numbers.
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Method Summary
All Methods Instance Methods Abstract Methods Concrete Methods Deprecated Methods Modifier and Type Method Description boolean
canParseAsync()
Method that can be called to determine if this parser instance uses non-blocking ("asynchronous") input access for decoding or not.boolean
canReadObjectId()
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
canReadTypeId()
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).boolean
canUseSchema(FormatSchema schema)
Method that can be used to verify that given schema can be used with this parser (usingsetSchema(com.fasterxml.jackson.core.FormatSchema)
).abstract void
clearCurrentToken()
Method called to "consume" the current token by effectively removing it so thathasCurrentToken()
returns false, andgetCurrentToken()
null).abstract void
close()
Closes the parser so that no further iteration or data access can be made; will also close the underlying input source if parser either owns the input source, or featureJsonParser.Feature.AUTO_CLOSE_SOURCE
is enabled.JsonParser
configure(JsonParser.Feature f, boolean state)
Method for enabling or disabling specified feature (checkJsonParser.Feature
for list of features)String
currentName()
JsonToken
currentToken()
Accessor to find which token parser currently points to, if any; null will be returned if none.int
currentTokenId()
JsonParser
disable(JsonParser.Feature f)
Method for disabling specified feature (checkJsonParser.Feature
for list of features)JsonParser
enable(JsonParser.Feature f)
Method for enabling specified parser feature (checkJsonParser.Feature
for list of features)void
finishToken()
Method that may be used to force full handling of the current token so that even if lazy processing is enabled, the whole contents are read for possible retrieval.abstract BigInteger
getBigIntegerValue()
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_INT
and it can not be used as a Java long primitive type due to its magnitude.byte[]
getBinaryValue()
Convenience alternative togetBinaryValue(Base64Variant)
that defaults to usingBase64Variants.getDefaultVariant()
as the default encoding.abstract byte[]
getBinaryValue(Base64Variant bv)
Method that can be used to read (and consume -- results may not be accessible using other methods after the call) base64-encoded binary data included in the current textual JSON value.boolean
getBooleanValue()
Convenience accessor that can be called when the current token isJsonToken.VALUE_TRUE
orJsonToken.VALUE_FALSE
.byte
getByteValue()
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_INT
and it can be expressed as a value of Java byte primitive type.abstract ObjectCodec
getCodec()
Accessor forObjectCodec
associated with this parser, if any.abstract JsonLocation
getCurrentLocation()
Method that returns location of the last processed character; usually for error reporting purposes.abstract String
getCurrentName()
Method that can be called to get the name associated with the current token: forJsonToken.FIELD_NAME
s it will be the same as whatgetText()
returns; for field values it will be preceding field name; and for others (array values, root-level values) null.abstract JsonToken
getCurrentToken()
Alias forcurrentToken()
, will be deprecated in Jackson 2.9abstract int
getCurrentTokenId()
Alias forcurrentTokenId()
, will be deprecated in Jackson 2.9Object
getCurrentValue()
Helper method, usually equivalent to:getParsingContext().getCurrentValue();
abstract BigDecimal
getDecimalValue()
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_FLOAT
orJsonToken.VALUE_NUMBER_INT
.abstract double
getDoubleValue()
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_FLOAT
and it can be expressed as a Java double primitive type.Object
getEmbeddedObject()
Accessor that can be called if (and only if) the current token isJsonToken.VALUE_EMBEDDED_OBJECT
.int
getFeatureMask()
Bulk access method for getting state of all standardJsonParser.Feature
s.abstract float
getFloatValue()
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_FLOAT
and it can be expressed as a Java float primitive type.int
getFormatFeatures()
Bulk access method for getting state of allFormatFeature
s, format-specific on/off configuration settings.Object
getInputSource()
Method that can be used to get access to object that is used to access input being parsed; this is usually eitherInputStream
orReader
, depending on what parser was constructed with.abstract int
getIntValue()
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_INT
and it can be expressed as a value of Java int primitive type.abstract JsonToken
getLastClearedToken()
Method that can be called to get the last token that was cleared usingclearCurrentToken()
.abstract long
getLongValue()
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_INT
and it can be expressed as a Java long primitive type.NonBlockingInputFeeder
getNonBlockingInputFeeder()
Method that will either return a feeder instance (if parser uses non-blocking, aka asynchronous access); ornull
for parsers that use blocking I/O.abstract JsonParser.NumberType
getNumberType()
If current token is of typeJsonToken.VALUE_NUMBER_INT
orJsonToken.VALUE_NUMBER_FLOAT
, returns one ofJsonParser.NumberType
constants; otherwise returns null.abstract Number
getNumberValue()
Generic number value accessor method that will work for all kinds of numeric values.Object
getObjectId()
Method that can be called to check whether current token (one that was just read) has an associated Object id, and if so, return it.abstract JsonStreamContext
getParsingContext()
Method that can be used to access current parsing context reader is in.FormatSchema
getSchema()
Method for accessing Schema that this parser uses, if any.short
getShortValue()
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_INT
and it can be expressed as a value of Java short primitive type.abstract String
getText()
Method for accessing textual representation of the current token; if no current token (before first call tonextToken()
, or after encountering end-of-input), returns null.int
getText(Writer writer)
Method to read the textual representation of the current token in chunks and pass it to the given Writer.abstract char[]
getTextCharacters()
Method similar togetText()
, but that will return underlying (unmodifiable) character array that contains textual value, instead of constructing a String object to contain this information.abstract int
getTextLength()
Accessor used withgetTextCharacters()
, to know length of String stored in returned buffer.abstract int
getTextOffset()
Accessor used withgetTextCharacters()
, to know offset of the first text content character within buffer.abstract JsonLocation
getTokenLocation()
Method that return the starting location of the current token; that is, position of the first character from input that starts the current token.Object
getTypeId()
Method that can be called to check whether current token (one that was just read) has an associated type id, and if so, return it.boolean
getValueAsBoolean()
Method that will try to convert value of current token to a boolean.boolean
getValueAsBoolean(boolean def)
Method that will try to convert value of current token to a boolean.double
getValueAsDouble()
Method that will try to convert value of current token to a Java double.double
getValueAsDouble(double def)
Method that will try to convert value of current token to a Java double.int
getValueAsInt()
Method that will try to convert value of current token to a int.int
getValueAsInt(int def)
Method that will try to convert value of current token to a int.long
getValueAsLong()
Method that will try to convert value of current token to a long.long
getValueAsLong(long def)
Method that will try to convert value of current token to a long.String
getValueAsString()
Method that will try to convert value of current token to aString
.abstract String
getValueAsString(String def)
Method that will try to convert value of current token to aString
.abstract boolean
hasCurrentToken()
Method for checking whether parser currently points to a token (and data for that token is available).abstract boolean
hasTextCharacters()
Method that can be used to determine whether calling ofgetTextCharacters()
would be the most efficient way to access textual content for the event parser currently points to.abstract boolean
hasToken(JsonToken t)
Method that is functionally equivalent to:return currentToken() == t
but may be more efficiently implemented.abstract boolean
hasTokenId(int id)
Method that is functionally equivalent to:return currentTokenId() == id
but may be more efficiently implemented.abstract boolean
isClosed()
Method that can be called to determine whether this parser is closed or not.boolean
isEnabled(JsonParser.Feature f)
Method for checking whether specifiedJsonParser.Feature
is enabled.boolean
isEnabled(StreamReadFeature f)
Method for checking whether specifiedJsonParser.Feature
is enabled.boolean
isExpectedStartArrayToken()
Specialized accessor that can be used to verify that the current token indicates start array (usually meaning that current token isJsonToken.START_ARRAY
) when start array is expected.boolean
isExpectedStartObjectToken()
Similar toisExpectedStartArrayToken()
, but checks whether stream currently points toJsonToken.START_OBJECT
.boolean
isNaN()
Access for checking whether current token is a numeric value token, but one that is of "not-a-number" (NaN) variety (including both "NaN" AND positive/negative infinity!): not supported by all formats, but often supported forJsonToken.VALUE_NUMBER_FLOAT
.Boolean
nextBooleanValue()
Method that fetches next token (as if callingnextToken()
) and if it isJsonToken.VALUE_TRUE
orJsonToken.VALUE_FALSE
returns matching Boolean value; otherwise return null.String
nextFieldName()
Method that fetches next token (as if callingnextToken()
) and verifies whether it isJsonToken.FIELD_NAME
; if it is, returns same asgetCurrentName()
, otherwise null.boolean
nextFieldName(SerializableString str)
Method that fetches next token (as if callingnextToken()
) and verifies whether it isJsonToken.FIELD_NAME
with specified name and returns result of that comparison.int
nextIntValue(int defaultValue)
Method that fetches next token (as if callingnextToken()
) and if it isJsonToken.VALUE_NUMBER_INT
returns 32-bit int value; otherwise returns specified default value It is functionally equivalent to:long
nextLongValue(long defaultValue)
Method that fetches next token (as if callingnextToken()
) and if it isJsonToken.VALUE_NUMBER_INT
returns 64-bit long value; otherwise returns specified default value It is functionally equivalent to:String
nextTextValue()
Method that fetches next token (as if callingnextToken()
) and if it isJsonToken.VALUE_STRING
returns contained String value; otherwise returns null.abstract JsonToken
nextToken()
Main iteration method, which will advance stream enough to determine type of the next token, if any.abstract JsonToken
nextValue()
Iteration method that will advance stream enough to determine type of the next token that is a value type (including JSON Array and Object start/end markers).abstract void
overrideCurrentName(String name)
Method that can be used to change what is considered to be the current (field) name.JsonParser
overrideFormatFeatures(int values, int mask)
Bulk set method for (re)setting states ofFormatFeature
s, by specifying values (set / clear) along with a mask, to determine which features to change, if any.JsonParser
overrideStdFeatures(int values, int mask)
Bulk set method for (re)setting states of features specified bymask
.int
readBinaryValue(Base64Variant bv, OutputStream out)
Similar toreadBinaryValue(OutputStream)
but allows explicitly specifying base64 variant to use.int
readBinaryValue(OutputStream out)
Method that can be used as an alternative togetBigIntegerValue()
, especially when value can be large.<T> T
readValueAs(TypeReference<?> valueTypeRef)
Method to deserialize JSON content into a Java type, reference to which is passed as argument.<T> T
readValueAs(Class<T> valueType)
Method to deserialize JSON content into a non-container type (it can be an array type, however): typically a bean, array or a wrapper type (likeBoolean
).<T extends TreeNode>
TreadValueAsTree()
Method to deserialize JSON content into equivalent "tree model", represented by rootTreeNode
of resulting model.<T> Iterator<T>
readValuesAs(TypeReference<T> valueTypeRef)
Method for reading sequence of Objects from parser stream, all with same specified value type.<T> Iterator<T>
readValuesAs(Class<T> valueType)
Method for reading sequence of Objects from parser stream, all with same specified value type.int
releaseBuffered(OutputStream out)
Method that can be called to push back any content that has been read but not consumed by the parser.int
releaseBuffered(Writer w)
Method that can be called to push back any content that has been read but not consumed by the parser.boolean
requiresCustomCodec()
Method that can be called to determine if a customObjectCodec
is needed for binding data parsed usingJsonParser
constructed by this factory (which typically also implies the same for serialization withJsonGenerator
).abstract void
setCodec(ObjectCodec c)
Setter that allows definingObjectCodec
associated with this parser, if any.void
setCurrentValue(Object v)
Helper method, usually equivalent to:getParsingContext().setCurrentValue(v);
JsonParser
setFeatureMask(int mask)
Deprecated.Since 2.7, useoverrideStdFeatures(int, int)
insteadvoid
setRequestPayloadOnError(byte[] payload, String charset)
Sets the byte[] request payload and the charsetvoid
setRequestPayloadOnError(RequestPayload payload)
Sets the payload to be passed ifJsonParseException
is thrown.void
setRequestPayloadOnError(String payload)
Sets the String request payloadvoid
setSchema(FormatSchema schema)
Method to call to make this parser use specified schema.abstract JsonParser
skipChildren()
Method that will skip all child tokens of an array or object token that the parser currently points to, iff stream points toJsonToken.START_OBJECT
orJsonToken.START_ARRAY
.abstract Version
version()
Accessor for getting version of the core package, given a parser instance.
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Method Detail
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getCodec
public abstract ObjectCodec getCodec()
Accessor forObjectCodec
associated with this parser, if any. Codec is used byreadValueAs(Class)
method (and its variants).
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setCodec
public abstract void setCodec(ObjectCodec c)
Setter that allows definingObjectCodec
associated with this parser, if any. Codec is used byreadValueAs(Class)
method (and its variants).
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getInputSource
public Object getInputSource()
Method that can be used to get access to object that is used to access input being parsed; this is usually eitherInputStream
orReader
, depending on what parser was constructed with. Note that returned value may be null in some cases; including case where parser implementation does not want to exposed raw source to caller. In cases where input has been decorated, object returned here is the decorated version; this allows some level of interaction between users of parser 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.
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getCurrentValue
public Object getCurrentValue()
Helper method, usually equivalent to:getParsingContext().getCurrentValue();
Note that "current value" is NOT populated (or used) by Streaming parser; it is only used by higher-level data-binding functionality. The reason it is included here is that it can be stored and accessed hierarchically, and gets passed through data-binding.
- Since:
- 2.5
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setCurrentValue
public void setCurrentValue(Object v)
Helper method, usually equivalent to:getParsingContext().setCurrentValue(v);
- Since:
- 2.5
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setRequestPayloadOnError
public void setRequestPayloadOnError(RequestPayload payload)
Sets the payload to be passed ifJsonParseException
is thrown.- Since:
- 2.8
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setRequestPayloadOnError
public void setRequestPayloadOnError(byte[] payload, String charset)
Sets the byte[] request payload and the charset- Since:
- 2.8
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setRequestPayloadOnError
public void setRequestPayloadOnError(String payload)
Sets the String request payload- Since:
- 2.8
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setSchema
public void setSchema(FormatSchema schema)
Method to call to make this parser use specified schema. Method must be called before trying to parse any content, right after parser instance has been created. Note that not all parsers support schemas; and those that do usually only accept specific types of schemas: ones defined for data format parser can read.If parser does not support specified schema,
UnsupportedOperationException
is thrown.- Parameters:
schema
- Schema to use- Throws:
UnsupportedOperationException
- if parser does not support schema
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getSchema
public FormatSchema getSchema()
Method for accessing Schema that this parser uses, if any. Default implementation returns null.- Since:
- 2.1
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canUseSchema
public boolean canUseSchema(FormatSchema schema)
Method that can be used to verify that given schema can be used with this parser (usingsetSchema(com.fasterxml.jackson.core.FormatSchema)
).- Parameters:
schema
- Schema to check- Returns:
- True if this parser can use given schema; false if not
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requiresCustomCodec
public boolean requiresCustomCodec()
Method that can be called to determine if a customObjectCodec
is needed for binding data parsed usingJsonParser
constructed by this factory (which typically also implies the same for serialization withJsonGenerator
).- Returns:
- True if custom codec is needed with parsers and
generators created by this factory; false if a general
ObjectCodec
is enough - Since:
- 2.1
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canParseAsync
public boolean canParseAsync()
Method that can be called to determine if this parser instance uses non-blocking ("asynchronous") input access for decoding or not. Access mode is determined by earlier calls viaJsonFactory
; it may not be changed after construction.If non-blocking decoding is u (@code true}, it is possible to call
getNonBlockingInputFeeder()
to obtain object to use for feeding input; otherwise (false
returned) input is read by blocking- Since:
- 2.9
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getNonBlockingInputFeeder
public NonBlockingInputFeeder getNonBlockingInputFeeder()
Method that will either return a feeder instance (if parser uses non-blocking, aka asynchronous access); ornull
for parsers that use blocking I/O.- Since:
- 2.9
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version
public abstract Version version()
Accessor for getting version of the core package, given a parser instance. Left for sub-classes to implement.
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close
public abstract void close() throws IOException
Closes the parser so that no further iteration or data access can be made; will also close the underlying input source if parser either owns the input source, or featureJsonParser.Feature.AUTO_CLOSE_SOURCE
is enabled. Whether parser owns the input source depends on factory method that was used to construct instance (so checkJsonFactory
for details, but the general idea is that if caller passes in closable resource (such asInputStream
orReader
) parser does NOT own the source; but if it passes a reference (such asFile
orURL
and creates stream or reader it does own them.- Specified by:
close
in interfaceAutoCloseable
- Specified by:
close
in interfaceCloseable
- Throws:
IOException
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isClosed
public abstract boolean isClosed()
Method that can be called to determine whether this parser is closed or not. If it is closed, no new tokens can be retrieved by callingnextToken()
(and the underlying stream may be closed). Closing may be due to an explicit call toclose()
or because parser has encountered end of input.
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getParsingContext
public abstract JsonStreamContext getParsingContext()
Method that can be used to access current parsing context reader is in. There are 3 different types: root, array and object contexts, with slightly different available information. Contexts are hierarchically nested, and can be used for example for figuring out part of the input document that correspond to specific array or object (for highlighting purposes, or error reporting). Contexts can also be used for simple xpath-like matching of input, if so desired.
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getTokenLocation
public abstract JsonLocation getTokenLocation()
Method that return the starting location of the current token; that is, position of the first character from input that starts the current token.
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getCurrentLocation
public abstract JsonLocation getCurrentLocation()
Method that returns location of the last processed character; usually for error reporting purposes.
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releaseBuffered
public int releaseBuffered(OutputStream out) throws IOException
Method that can be called to push back any content that has been read but not consumed by the parser. This is usually done after reading all content of interest using parser. Content is released by writing it to given stream if possible; if underlying input is byte-based it can released, if not (char-based) it can not.- Returns:
- -1 if the underlying content source is not byte based
(that is, input can not be sent to
OutputStream
; otherwise number of bytes released (0 if there was nothing to release) - Throws:
IOException
- if write to stream threw exception
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releaseBuffered
public int releaseBuffered(Writer w) throws IOException
Method that can be called to push back any content that has been read but not consumed by the parser. This is usually done after reading all content of interest using parser. Content is released by writing it to given writer if possible; if underlying input is char-based it can released, if not (byte-based) it can not.- Returns:
- -1 if the underlying content source is not char-based
(that is, input can not be sent to
Writer
; otherwise number of chars released (0 if there was nothing to release) - Throws:
IOException
- if write using Writer threw exception
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enable
public JsonParser enable(JsonParser.Feature f)
Method for enabling specified parser feature (checkJsonParser.Feature
for list of features)
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disable
public JsonParser disable(JsonParser.Feature f)
Method for disabling specified feature (checkJsonParser.Feature
for list of features)
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configure
public JsonParser configure(JsonParser.Feature f, boolean state)
Method for enabling or disabling specified feature (checkJsonParser.Feature
for list of features)
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isEnabled
public boolean isEnabled(JsonParser.Feature f)
Method for checking whether specifiedJsonParser.Feature
is enabled.
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isEnabled
public boolean isEnabled(StreamReadFeature f)
Method for checking whether specifiedJsonParser.Feature
is enabled.- Since:
- 2.10
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getFeatureMask
public int getFeatureMask()
Bulk access method for getting state of all standardJsonParser.Feature
s.- Returns:
- Bit mask that defines current states of all standard
JsonParser.Feature
s. - Since:
- 2.3
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setFeatureMask
@Deprecated public JsonParser setFeatureMask(int mask)
Deprecated.Since 2.7, useoverrideStdFeatures(int, int)
insteadBulk set method for (re)setting states of all standardJsonParser.Feature
s- Returns:
- This parser object, to allow chaining of calls
- Since:
- 2.3
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overrideStdFeatures
public JsonParser overrideStdFeatures(int values, int mask)
Bulk set method for (re)setting states of features specified bymask
. Functionally equivalent toint oldState = getFeatureMask(); int newState = (oldState & ~mask) | (values & mask); setFeatureMask(newState);
but preferred as this lets caller more efficiently specify actual changes made.- Parameters:
values
- Bit mask of set/clear state for features to changemask
- Bit mask of features to change- Since:
- 2.6
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getFormatFeatures
public int getFormatFeatures()
Bulk access method for getting state of allFormatFeature
s, format-specific on/off configuration settings.- Returns:
- Bit mask that defines current states of all standard
FormatFeature
s. - Since:
- 2.6
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overrideFormatFeatures
public JsonParser overrideFormatFeatures(int values, int mask)
Bulk set method for (re)setting states ofFormatFeature
s, by specifying values (set / clear) along with a mask, to determine which features to change, if any.Default implementation will simply throw an exception to indicate that the generator implementation does not support any
FormatFeature
s.- Parameters:
values
- Bit mask of set/clear state for features to changemask
- Bit mask of features to change- Since:
- 2.6
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nextToken
public abstract JsonToken nextToken() throws IOException
Main iteration method, which will advance stream enough to determine type of the next token, if any. If none remaining (stream has no content other than possible white space before ending), null will be returned.- Returns:
- Next token from the stream, if any found, or null to indicate end-of-input
- Throws:
IOException
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nextValue
public abstract JsonToken nextValue() throws IOException
Iteration method that will advance stream enough to determine type of the next token that is a value type (including JSON Array and Object start/end markers). Or put another way, nextToken() will be called once, and ifJsonToken.FIELD_NAME
is returned, another time to get the value for the field. Method is most useful for iterating over value entries of JSON objects; field name will still be available by callinggetCurrentName()
when parser points to the value.- Returns:
- Next non-field-name token from the stream, if any found,
or null to indicate end-of-input (or, for non-blocking
parsers,
JsonToken.NOT_AVAILABLE
if no tokens were available yet) - Throws:
IOException
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nextFieldName
public boolean nextFieldName(SerializableString str) throws IOException
Method that fetches next token (as if callingnextToken()
) and verifies whether it isJsonToken.FIELD_NAME
with specified name and returns result of that comparison. It is functionally equivalent to:return (nextToken() == JsonToken.FIELD_NAME) && str.getValue().equals(getCurrentName());
but may be faster for parser to verify, and can therefore be used if caller expects to get such a property name from input next.- Parameters:
str
- Property name to compare next token to (if next token isJsonToken.FIELD_NAME
)- Throws:
IOException
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nextFieldName
public String nextFieldName() throws IOException
Method that fetches next token (as if callingnextToken()
) and verifies whether it isJsonToken.FIELD_NAME
; if it is, returns same asgetCurrentName()
, otherwise null.- Throws:
IOException
- Since:
- 2.5
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nextTextValue
public String nextTextValue() throws IOException
Method that fetches next token (as if callingnextToken()
) and if it isJsonToken.VALUE_STRING
returns contained String value; otherwise returns null. It is functionally equivalent to:return (nextToken() == JsonToken.VALUE_STRING) ? getText() : null;
but may be faster for parser to process, and can therefore be used if caller expects to get a String value next from input.- Throws:
IOException
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nextIntValue
public int nextIntValue(int defaultValue) throws IOException
Method that fetches next token (as if callingnextToken()
) and if it isJsonToken.VALUE_NUMBER_INT
returns 32-bit int value; otherwise returns specified default value It is functionally equivalent to:return (nextToken() == JsonToken.VALUE_NUMBER_INT) ? getIntValue() : defaultValue;
but may be faster for parser to process, and can therefore be used if caller expects to get an int value next from input.- Throws:
IOException
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nextLongValue
public long nextLongValue(long defaultValue) throws IOException
Method that fetches next token (as if callingnextToken()
) and if it isJsonToken.VALUE_NUMBER_INT
returns 64-bit long value; otherwise returns specified default value It is functionally equivalent to:return (nextToken() == JsonToken.VALUE_NUMBER_INT) ? getLongValue() : defaultValue;
but may be faster for parser to process, and can therefore be used if caller expects to get a long value next from input.- Throws:
IOException
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nextBooleanValue
public Boolean nextBooleanValue() throws IOException
Method that fetches next token (as if callingnextToken()
) and if it isJsonToken.VALUE_TRUE
orJsonToken.VALUE_FALSE
returns matching Boolean value; otherwise return null. It is functionally equivalent to:JsonToken t = nextToken(); if (t == JsonToken.VALUE_TRUE) return Boolean.TRUE; if (t == JsonToken.VALUE_FALSE) return Boolean.FALSE; return null;
but may be faster for parser to process, and can therefore be used if caller expects to get a Boolean value next from input.- Throws:
IOException
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skipChildren
public abstract JsonParser skipChildren() throws IOException
Method that will skip all child tokens of an array or object token that the parser currently points to, iff stream points toJsonToken.START_OBJECT
orJsonToken.START_ARRAY
. If not, it will do nothing. After skipping, stream will point to matchingJsonToken.END_OBJECT
orJsonToken.END_ARRAY
(possibly skipping nested pairs of START/END OBJECT/ARRAY tokens as well as value tokens). The idea is that after calling this method, application will callnextToken()
to point to the next available token, if any.- Throws:
IOException
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finishToken
public void finishToken() throws IOException
Method that may be used to force full handling of the current token so that even if lazy processing is enabled, the whole contents are read for possible retrieval. This is usually used to ensure that the token end location is available, as well as token contents (similar to what calling, saygetTextCharacters()
, would achieve).Note that for many dataformat implementations this method will not do anything; this is the default implementation unless overridden by sub-classes.
- Throws:
IOException
- Since:
- 2.8
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currentToken
public JsonToken currentToken()
Accessor to find which token parser currently points to, if any; null will be returned if none. If return value is non-null, data associated with the token is available via other accessor methods.- Returns:
- Type of the token this parser currently points to, if any: null before any tokens have been read, and after end-of-input has been encountered, as well as if the current token has been explicitly cleared.
- Since:
- 2.8
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currentTokenId
public int currentTokenId()
Method similar togetCurrentToken()
but that returns anint
instead ofJsonToken
(enum value).Use of int directly is typically more efficient on switch statements, so this method may be useful when building low-overhead codecs. Note, however, that effect may not be big enough to matter: make sure to profile performance before deciding to use this method.
- Returns:
int
matching one of constants fromJsonTokenId
.- Since:
- 2.8
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getCurrentToken
public abstract JsonToken getCurrentToken()
Alias forcurrentToken()
, will be deprecated in Jackson 2.9
-
getCurrentTokenId
public abstract int getCurrentTokenId()
Alias forcurrentTokenId()
, will be deprecated in Jackson 2.9
-
hasCurrentToken
public abstract boolean hasCurrentToken()
Method for checking whether parser currently points to a token (and data for that token is available). Equivalent to check forparser.getCurrentToken() != null
.- Returns:
- True if the parser just returned a valid
token via
nextToken()
; false otherwise (parser was just constructed, encountered end-of-input and returned null fromnextToken()
, or the token has been consumed)
-
hasTokenId
public abstract boolean hasTokenId(int id)
Method that is functionally equivalent to:return currentTokenId() == id
but may be more efficiently implemented.Note that no traversal or conversion is performed; so in some cases calling method like
isExpectedStartArrayToken()
is necessary instead.- Since:
- 2.5
-
hasToken
public abstract boolean hasToken(JsonToken t)
Method that is functionally equivalent to:return currentToken() == t
but may be more efficiently implemented.Note that no traversal or conversion is performed; so in some cases calling method like
isExpectedStartArrayToken()
is necessary instead.- Since:
- 2.6
-
isExpectedStartArrayToken
public boolean isExpectedStartArrayToken()
Specialized accessor that can be used to verify that the current token indicates start array (usually meaning that current token isJsonToken.START_ARRAY
) when start array is expected. For some specialized parsers this can return true for other cases as well; this is usually done to emulate arrays in cases underlying format is ambiguous (XML, for example, has no format-level difference between Objects and Arrays; it just has elements).Default implementation is equivalent to:
currentToken() == JsonToken.START_ARRAY
but may be overridden by custom parser implementations.- Returns:
- True if the current token can be considered as a
start-array marker (such
JsonToken.START_ARRAY
); false if not.
-
isExpectedStartObjectToken
public boolean isExpectedStartObjectToken()
Similar toisExpectedStartArrayToken()
, but checks whether stream currently points toJsonToken.START_OBJECT
.- Since:
- 2.5
-
isNaN
public boolean isNaN() throws IOException
Access for checking whether current token is a numeric value token, but one that is of "not-a-number" (NaN) variety (including both "NaN" AND positive/negative infinity!): not supported by all formats, but often supported forJsonToken.VALUE_NUMBER_FLOAT
. NOTE: roughly equivalent to calling!Double.isFinite()
on value you would get from callinggetDoubleValue()
.- Throws:
IOException
- Since:
- 2.9
-
clearCurrentToken
public abstract void clearCurrentToken()
Method called to "consume" the current token by effectively removing it so thathasCurrentToken()
returns false, andgetCurrentToken()
null). Cleared token value can still be accessed by callinggetLastClearedToken()
(if absolutely needed), but usually isn't.Method was added to be used by the optional data binder, since it has to be able to consume last token used for binding (so that it will not be used again).
-
getLastClearedToken
public abstract JsonToken getLastClearedToken()
Method that can be called to get the last token that was cleared usingclearCurrentToken()
. This is not necessarily the latest token read. Will return null if no tokens have been cleared, or if parser has been closed.
-
overrideCurrentName
public abstract void overrideCurrentName(String name)
Method that can be used to change what is considered to be the current (field) name. May be needed to support non-JSON data formats or unusual binding conventions; not needed for typical processing.Note that use of this method should only be done as sort of last resort, as it is a work-around for regular operation.
- Parameters:
name
- Name to use as the current name; may be null.
-
getCurrentName
public abstract String getCurrentName() throws IOException
Method that can be called to get the name associated with the current token: forJsonToken.FIELD_NAME
s it will be the same as whatgetText()
returns; for field values it will be preceding field name; and for others (array values, root-level values) null.- Throws:
IOException
-
currentName
public String currentName() throws IOException
- Throws:
IOException
-
getText
public abstract String getText() throws IOException
Method for accessing textual representation of the current token; if no current token (before first call tonextToken()
, or after encountering end-of-input), returns null. Method can be called for any token type.- Throws:
IOException
-
getText
public int getText(Writer writer) throws IOException, UnsupportedOperationException
Method to read the textual representation of the current token in chunks and pass it to the given Writer. Conceptually same as calling:writer.write(parser.getText());
but should typically be more efficient as longer content does need to be combined into a singleString
to return, and write can occur directly from intermediate buffers Jackson uses.- Returns:
- The number of characters written to the Writer
- Throws:
IOException
UnsupportedOperationException
- Since:
- 2.8
-
getTextCharacters
public abstract char[] getTextCharacters() throws IOException
Method similar togetText()
, but that will return underlying (unmodifiable) character array that contains textual value, instead of constructing a String object to contain this information. Note, however, that:- Textual contents are not guaranteed to start at
index 0 (rather, call
getTextOffset()
) to know the actual offset - Length of textual contents may be less than the
length of returned buffer: call
getTextLength()
for actual length of returned content.
Note that caller MUST NOT modify the returned character array in any way -- doing so may corrupt current parser state and render parser instance useless.
The only reason to call this method (over
getText()
) is to avoid construction of a String object (which will make a copy of contents).- Throws:
IOException
- Textual contents are not guaranteed to start at
index 0 (rather, call
-
getTextLength
public abstract int getTextLength() throws IOException
Accessor used withgetTextCharacters()
, to know length of String stored in returned buffer.- Returns:
- Number of characters within buffer returned
by
getTextCharacters()
that are part of textual content of the current token. - Throws:
IOException
-
getTextOffset
public abstract int getTextOffset() throws IOException
Accessor used withgetTextCharacters()
, to know offset of the first text content character within buffer.- Returns:
- Offset of the first character within buffer returned
by
getTextCharacters()
that is part of textual content of the current token. - Throws:
IOException
-
hasTextCharacters
public abstract boolean hasTextCharacters()
Method that can be used to determine whether calling ofgetTextCharacters()
would be the most efficient way to access textual content for the event parser currently points to.Default implementation simply returns false since only actual implementation class has knowledge of its internal buffering state. Implementations are strongly encouraged to properly override this method, to allow efficient copying of content by other code.
- Returns:
- True if parser currently has character array that can
be efficiently returned via
getTextCharacters()
; false means that it may or may not exist
-
getNumberValue
public abstract Number getNumberValue() throws IOException
Generic number value accessor method that will work for all kinds of numeric values. It will return the optimal (simplest/smallest possible) wrapper object that can express the numeric value just parsed.- Throws:
IOException
-
getNumberType
public abstract JsonParser.NumberType getNumberType() throws IOException
If current token is of typeJsonToken.VALUE_NUMBER_INT
orJsonToken.VALUE_NUMBER_FLOAT
, returns one ofJsonParser.NumberType
constants; otherwise returns null.- Throws:
IOException
-
getByteValue
public byte getByteValue() throws IOException
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_INT
and it can be expressed as a value of Java byte primitive type. It can also be called forJsonToken.VALUE_NUMBER_FLOAT
; if so, it is equivalent to callinggetDoubleValue()
and then casting; except for possible overflow/underflow exception.Note: if the resulting integer value falls outside range of Java byte, a
JsonParseException
will be thrown to indicate numeric overflow/underflow.- Throws:
IOException
-
getShortValue
public short getShortValue() throws IOException
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_INT
and it can be expressed as a value of Java short primitive type. It can also be called forJsonToken.VALUE_NUMBER_FLOAT
; if so, it is equivalent to callinggetDoubleValue()
and then casting; except for possible overflow/underflow exception.Note: if the resulting integer value falls outside range of Java short, a
JsonParseException
will be thrown to indicate numeric overflow/underflow.- Throws:
IOException
-
getIntValue
public abstract int getIntValue() throws IOException
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_INT
and it can be expressed as a value of Java int primitive type. It can also be called forJsonToken.VALUE_NUMBER_FLOAT
; if so, it is equivalent to callinggetDoubleValue()
and then casting; except for possible overflow/underflow exception.Note: if the resulting integer value falls outside range of Java int, a
JsonParseException
may be thrown to indicate numeric overflow/underflow.- Throws:
IOException
-
getLongValue
public abstract long getLongValue() throws IOException
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_INT
and it can be expressed as a Java long primitive type. It can also be called forJsonToken.VALUE_NUMBER_FLOAT
; if so, it is equivalent to callinggetDoubleValue()
and then casting to int; except for possible overflow/underflow exception.Note: if the token is an integer, but its value falls outside of range of Java long, a
JsonParseException
may be thrown to indicate numeric overflow/underflow.- Throws:
IOException
-
getBigIntegerValue
public abstract BigInteger getBigIntegerValue() throws IOException
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_INT
and it can not be used as a Java long primitive type due to its magnitude. It can also be called forJsonToken.VALUE_NUMBER_FLOAT
; if so, it is equivalent to callinggetDecimalValue()
and then constructing aBigInteger
from that value.- Throws:
IOException
-
getFloatValue
public abstract float getFloatValue() throws IOException
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_FLOAT
and it can be expressed as a Java float primitive type. It can also be called forJsonToken.VALUE_NUMBER_INT
; if so, it is equivalent to callinggetLongValue()
and then casting; except for possible overflow/underflow exception.Note: if the value falls outside of range of Java float, a
JsonParseException
will be thrown to indicate numeric overflow/underflow.- Throws:
IOException
-
getDoubleValue
public abstract double getDoubleValue() throws IOException
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_FLOAT
and it can be expressed as a Java double primitive type. It can also be called forJsonToken.VALUE_NUMBER_INT
; if so, it is equivalent to callinggetLongValue()
and then casting; except for possible overflow/underflow exception.Note: if the value falls outside of range of Java double, a
JsonParseException
will be thrown to indicate numeric overflow/underflow.- Throws:
IOException
-
getDecimalValue
public abstract BigDecimal getDecimalValue() throws IOException
Numeric accessor that can be called when the current token is of typeJsonToken.VALUE_NUMBER_FLOAT
orJsonToken.VALUE_NUMBER_INT
. No under/overflow exceptions are ever thrown.- Throws:
IOException
-
getBooleanValue
public boolean getBooleanValue() throws IOException
Convenience accessor that can be called when the current token isJsonToken.VALUE_TRUE
orJsonToken.VALUE_FALSE
.Note: if the token is not of above-mentioned boolean types, an integer, but its value falls outside of range of Java long, a
JsonParseException
may be thrown to indicate numeric overflow/underflow.- Throws:
IOException
-
getEmbeddedObject
public Object getEmbeddedObject() throws IOException
Accessor that can be called if (and only if) the current token isJsonToken.VALUE_EMBEDDED_OBJECT
. For other token types, null is returned.Note: only some specialized parser implementations support embedding of objects (usually ones that are facades on top of non-streaming sources, such as object trees). One exception is access to binary content (whether via base64 encoding or not) which typically is accessible using this method, as well as
getBinaryValue()
.- Throws:
IOException
-
getBinaryValue
public abstract byte[] getBinaryValue(Base64Variant bv) throws IOException
Method that can be used to read (and consume -- results may not be accessible using other methods after the call) base64-encoded binary data included in the current textual JSON value. It works similar to getting String value viagetText()
and decoding result (except for decoding part), but should be significantly more performant.Note that non-decoded textual contents of the current token are not guaranteed to be accessible after this method is called. Current implementation, for example, clears up textual content during decoding. Decoded binary content, however, will be retained until parser is advanced to the next event.
- Parameters:
bv
- Expected variant of base64 encoded content (seeBase64Variants
for definitions of "standard" variants).- Returns:
- Decoded binary data
- Throws:
IOException
-
getBinaryValue
public byte[] getBinaryValue() throws IOException
Convenience alternative togetBinaryValue(Base64Variant)
that defaults to usingBase64Variants.getDefaultVariant()
as the default encoding.- Throws:
IOException
-
readBinaryValue
public int readBinaryValue(OutputStream out) throws IOException
Method that can be used as an alternative togetBigIntegerValue()
, especially when value can be large. The main difference (beyond method of returning content usingOutputStream
instead of as byte array) is that content will NOT remain accessible after method returns: any content processed will be consumed and is not buffered in any way. If caller needs buffering, it has to implement it.- Parameters:
out
- Output stream to use for passing decoded binary data- Returns:
- Number of bytes that were decoded and written via
OutputStream
- Throws:
IOException
- Since:
- 2.1
-
readBinaryValue
public int readBinaryValue(Base64Variant bv, OutputStream out) throws IOException
Similar toreadBinaryValue(OutputStream)
but allows explicitly specifying base64 variant to use.- Parameters:
bv
- base64 variant to useout
- Output stream to use for passing decoded binary data- Returns:
- Number of bytes that were decoded and written via
OutputStream
- Throws:
IOException
- Since:
- 2.1
-
getValueAsInt
public int getValueAsInt() throws IOException
Method that will try to convert value of current token to a int. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.If representation can not be converted to an int (including structured type markers like start/end Object/Array) default value of 0 will be returned; no exceptions are thrown.
- Throws:
IOException
-
getValueAsInt
public int getValueAsInt(int def) throws IOException
Method that will try to convert value of current token to a int. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.If representation can not be converted to an int (including structured type markers like start/end Object/Array) specified def will be returned; no exceptions are thrown.
- Throws:
IOException
-
getValueAsLong
public long getValueAsLong() throws IOException
Method that will try to convert value of current token to a long. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.If representation can not be converted to a long (including structured type markers like start/end Object/Array) default value of 0L will be returned; no exceptions are thrown.
- Throws:
IOException
-
getValueAsLong
public long getValueAsLong(long def) throws IOException
Method that will try to convert value of current token to a long. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.If representation can not be converted to a long (including structured type markers like start/end Object/Array) specified def will be returned; no exceptions are thrown.
- Throws:
IOException
-
getValueAsDouble
public double getValueAsDouble() throws IOException
Method that will try to convert value of current token to a Java double. Numbers are coerced using default Java rules; booleans convert to 0.0 (false) and 1.0 (true), and Strings are parsed using default Java language floating point parsing rules.If representation can not be converted to a double (including structured types like Objects and Arrays), default value of 0.0 will be returned; no exceptions are thrown.
- Throws:
IOException
-
getValueAsDouble
public double getValueAsDouble(double def) throws IOException
Method that will try to convert value of current token to a Java double. Numbers are coerced using default Java rules; booleans convert to 0.0 (false) and 1.0 (true), and Strings are parsed using default Java language floating point parsing rules.If representation can not be converted to a double (including structured types like Objects and Arrays), specified def will be returned; no exceptions are thrown.
- Throws:
IOException
-
getValueAsBoolean
public boolean getValueAsBoolean() throws IOException
Method that will try to convert value of current token to a boolean. JSON booleans map naturally; integer numbers other than 0 map to true, and 0 maps to false and Strings 'true' and 'false' map to corresponding values.If representation can not be converted to a boolean value (including structured types like Objects and Arrays), default value of false will be returned; no exceptions are thrown.
- Throws:
IOException
-
getValueAsBoolean
public boolean getValueAsBoolean(boolean def) throws IOException
Method that will try to convert value of current token to a boolean. JSON booleans map naturally; integer numbers other than 0 map to true, and 0 maps to false and Strings 'true' and 'false' map to corresponding values.If representation can not be converted to a boolean value (including structured types like Objects and Arrays), specified def will be returned; no exceptions are thrown.
- Throws:
IOException
-
getValueAsString
public String getValueAsString() throws IOException
Method that will try to convert value of current token to aString
. JSON Strings map naturally; scalar values get converted to their textual representation. If representation can not be converted to a String value (including structured types like Objects and Arrays and null token), default value of null will be returned; no exceptions are thrown.- Throws:
IOException
- Since:
- 2.1
-
getValueAsString
public abstract String getValueAsString(String def) throws IOException
Method that will try to convert value of current token to aString
. JSON Strings map naturally; scalar values get converted to their textual representation. If representation can not be converted to a String value (including structured types like Objects and Arrays and null token), specified default value will be returned; no exceptions are thrown.- Throws:
IOException
- Since:
- 2.1
-
canReadObjectId
public boolean canReadObjectId()
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).Default implementation returns true; 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
-
canReadTypeId
public boolean canReadTypeId()
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).Default implementation returns true; 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
-
getObjectId
public Object getObjectId() throws IOException
Method that can be called to check whether current token (one that was just read) has an associated Object id, and if so, return it. Note that while typically caller should check withcanReadObjectId()
first, it is not illegal to call this method even if that method returns true; but if so, it will return null. This may be used to simplify calling code.Default implementation will simply return null.
- Throws:
IOException
- Since:
- 2.3
-
getTypeId
public Object getTypeId() throws IOException
Method that can be called to check whether current token (one that was just read) has an associated type id, and if so, return it. Note that while typically caller should check withcanReadTypeId()
first, it is not illegal to call this method even if that method returns true; but if so, it will return null. This may be used to simplify calling code.Default implementation will simply return null.
- Throws:
IOException
- Since:
- 2.3
-
readValueAs
public <T> T readValueAs(Class<T> valueType) throws IOException
Method to deserialize JSON content into a non-container type (it can be an array type, however): typically a bean, array or a wrapper type (likeBoolean
). Note: method can only be called if the parser has an object codec assigned; this is true for parsers constructed byMappingJsonFactory
(from "jackson-databind" jar) but not forJsonFactory
(unless itssetCodec
method has been explicitly called).This method may advance the event stream, for structured types the current token will be the closing end marker (END_ARRAY, END_OBJECT) of the bound structure. For non-structured Json types (and for
JsonToken.VALUE_EMBEDDED_OBJECT
) stream is not advanced.Note: this method should NOT be used if the result type is a container (
Collection
orMap
. The reason is that due to type erasure, key and value types can not be introspected when using this method.- Throws:
IOException
-
readValueAs
public <T> T readValueAs(TypeReference<?> valueTypeRef) throws IOException
Method to deserialize JSON content into a Java type, reference to which is passed as argument. Type is passed using so-called "super type token" and specifically needs to be used if the root type is a parameterized (generic) container type. Note: method can only be called if the parser has an object codec assigned; this is true for parsers constructed byMappingJsonFactory
(defined in 'jackson-databind' bundle) but not forJsonFactory
(unless itssetCodec
method has been explicitly called).This method may advance the event stream, for structured types the current token will be the closing end marker (END_ARRAY, END_OBJECT) of the bound structure. For non-structured Json types (and for
JsonToken.VALUE_EMBEDDED_OBJECT
) stream is not advanced.- Throws:
IOException
-
readValuesAs
public <T> Iterator<T> readValuesAs(Class<T> valueType) throws IOException
Method for reading sequence of Objects from parser stream, all with same specified value type.- Throws:
IOException
-
readValuesAs
public <T> Iterator<T> readValuesAs(TypeReference<T> valueTypeRef) throws IOException
Method for reading sequence of Objects from parser stream, all with same specified value type.- Throws:
IOException
-
readValueAsTree
public <T extends TreeNode> T readValueAsTree() throws IOException
Method to deserialize JSON content into equivalent "tree model", represented by rootTreeNode
of resulting model. For JSON Arrays it will an array node (with child nodes), for objects object node (with child nodes), and for other types matching leaf node type. Empty or whitespace documents are null.- Returns:
- root of the document, or null if empty or whitespace.
- Throws:
IOException
-
-