com.fasterxml.jackson.core
Class JsonParser

java.lang.Object
  com.fasterxml.jackson.core.JsonParser

All Implemented Interfaces:

Versioned, Closeable

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 a JsonFactory instance.

Author:

Tatu Saloranta

Nested Class Summary

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.

Field Summary

protected int

_features Bit flag composed of bits that indicate which JsonParser.Features are enabled.

Constructor Summary

protected	JsonParser()
protected	JsonParser(int features)

Method Summary

protected ObjectCodec	_codec()
protected JsonParseException	_constructError(String msg) Helper method for constructing JsonParseExceptions based on current state of the parser
protected void	_reportUnsupportedOperation() Helper method to call for operations that are not supported by parser implementation.
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 (using setSchema(com.fasterxml.jackson.core.FormatSchema)).
abstract void	clearCurrentToken() Method called to "consume" the current token by effectively removing it so that hasCurrentToken() returns false, and getCurrentToken() 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 feature JsonParser.Feature.AUTO_CLOSE_SOURCE is enabled.
JsonParser	configure(JsonParser.Feature f, boolean state) Method for enabling or disabling specified feature (check JsonParser.Feature for list of features)
JsonParser	disable(JsonParser.Feature f) Method for disabling specified feature (check JsonParser.Feature for list of features)
JsonParser	enable(JsonParser.Feature f) Method for enabling specified parser feature (check JsonParser.Feature for list of features)
abstract BigInteger	getBigIntegerValue() Numeric accessor that can be called when the current token is of type JsonToken.VALUE_NUMBER_INT and it can not be used as a Java long primitive type due to its magnitude.
byte[]	getBinaryValue() Convenience alternative to getBinaryValue(Base64Variant) that defaults to using Base64Variants.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 is JsonToken.VALUE_TRUE or JsonToken.VALUE_FALSE.
byte	getByteValue() Numeric accessor that can be called when the current token is of type JsonToken.VALUE_NUMBER_INT and it can be expressed as a value of Java byte primitive type.
abstract ObjectCodec	getCodec() Accessor for ObjectCodec 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: for JsonToken.FIELD_NAMEs it will be the same as what getText() returns; for field values it will be preceding field name; and for others (array values, root-level values) null.
abstract JsonToken	getCurrentToken() Accessor to find which token parser currently points to, if any; null will be returned if none.
abstract int	getCurrentTokenId() Method similar to getCurrentToken() but that returns an int instead of JsonToken (enum value).
Object	getCurrentValue() Helper method, usually equivalent to: getParsingContext().getCurrentValue();
abstract BigDecimal	getDecimalValue() Numeric accessor that can be called when the current token is of type JsonToken.VALUE_NUMBER_FLOAT or JsonToken.VALUE_NUMBER_INT.
abstract double	getDoubleValue() Numeric accessor that can be called when the current token is of type JsonToken.VALUE_NUMBER_FLOAT and it can be expressed as a Java double primitive type.
abstract Object	getEmbeddedObject() Accessor that can be called if (and only if) the current token is JsonToken.VALUE_EMBEDDED_OBJECT.
int	getFeatureMask() Bulk access method for getting state of all standard JsonParser.Features.
abstract float	getFloatValue() Numeric accessor that can be called when the current token is of type JsonToken.VALUE_NUMBER_FLOAT and it can be expressed as a Java float primitive type.
int	getFormatFeatures() Bulk access method for getting state of all FormatFeatures, 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 either InputStream or Reader, depending on what parser was constructed with.
abstract int	getIntValue() Numeric accessor that can be called when the current token is of type JsonToken.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 using clearCurrentToken().
abstract long	getLongValue() Numeric accessor that can be called when the current token is of type JsonToken.VALUE_NUMBER_INT and it can be expressed as a Java long primitive type.
abstract JsonParser.NumberType	getNumberType() If current token is of type JsonToken.VALUE_NUMBER_INT or JsonToken.VALUE_NUMBER_FLOAT, returns one of JsonParser.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 type JsonToken.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 to nextToken(), or after encountering end-of-input), returns null.
abstract char[]	getTextCharacters() Method similar to getText(), 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 with getTextCharacters(), to know length of String stored in returned buffer.
abstract int	getTextOffset() Accessor used with getTextCharacters(), 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 a String.
abstract String	getValueAsString(String def) Method that will try to convert value of current token to a String.
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 of getTextCharacters() 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 getCurrentTokenId() == id but may be more efficiently implemented.
abstract boolean	hasTokenId(int id) Method that is functionally equivalent to: return getCurrentTokenId() == 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 specified JsonParser.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 is JsonToken.START_ARRAY) when start array is expected.
boolean	isExpectedStartObjectToken() Similar to isExpectedStartArrayToken(), but checks whether stream currently points to JsonToken.START_OBJECT.
Boolean	nextBooleanValue() Method that fetches next token (as if calling nextToken()) and if it is JsonToken.VALUE_TRUE or JsonToken.VALUE_FALSE returns matching Boolean value; otherwise return null.
String	nextFieldName() Method that fetches next token (as if calling nextToken()) and verifies whether it is JsonToken.FIELD_NAME; if it is, returns same as getCurrentName(), otherwise null.
boolean	nextFieldName(SerializableString str) Method that fetches next token (as if calling nextToken()) and verifies whether it is JsonToken.FIELD_NAME with specified name and returns result of that comparison.
int	nextIntValue(int defaultValue) Method that fetches next token (as if calling nextToken()) and if it is JsonToken.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 calling nextToken()) and if it is JsonToken.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 calling nextToken()) and if it is JsonToken.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 of FormatFeatures, 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 by mask.
int	readBinaryValue(Base64Variant bv, OutputStream out) Similar to readBinaryValue(OutputStream) but allows explicitly specifying base64 variant to use.
int	readBinaryValue(OutputStream out) Method that can be used as an alternative to getBigIntegerValue(), especially when value can be large.
<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 (like Boolean).
<T> T	readValueAs(TypeReference<?> valueTypeRef) Method to deserialize JSON content into a Java type, reference to which is passed as argument.
<T extends TreeNode> T	readValueAsTree() Method to deserialize JSON content into equivalent "tree model", represented by root TreeNode of resulting model.
<T> Iterator<T>	readValuesAs(Class<T> valueType) Method for reading sequence of Objects from parser stream, all with same specified value type.
<T> Iterator<T>	readValuesAs(TypeReference<?> valueTypeRef) 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 custom ObjectCodec is needed for binding data parsed using JsonParser constructed by this factory (which typically also implies the same for serialization with JsonGenerator).
abstract void	setCodec(ObjectCodec c) Setter that allows defining ObjectCodec 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, use overrideStdFeatures(int, int) instead
void	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 to JsonToken.START_OBJECT or JsonToken.START_ARRAY.
abstract Version	version() Accessor for getting version of the core package, given a parser instance.

Methods inherited from class java.lang.Object

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

Field Detail

_features

protected int _features

Bit flag composed of bits that indicate which JsonParser.Features are enabled.

Constructor Detail

JsonParser

protected JsonParser()

JsonParser

protected JsonParser(int features)

Method Detail

getCodec

public abstract ObjectCodec getCodec()

Accessor for ObjectCodec associated with this parser, if any. Codec is used by readValueAs(Class) method (and its variants).

setCodec

public abstract void setCodec(ObjectCodec c)

Setter that allows defining ObjectCodec associated with this parser, if any. Codec is used by readValueAs(Class) method (and its variants).

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 either InputStream or Reader, 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.

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

setCurrentValue

public void setCurrentValue(Object v)

Helper method, usually equivalent to: getParsingContext().setCurrentValue(v);

Since:

2.5

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

getSchema

public FormatSchema getSchema()

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

Since:

2.1

canUseSchema

public boolean canUseSchema(FormatSchema schema)

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

Parameters:

schema - Schema to check

Returns:

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

requiresCustomCodec

public boolean requiresCustomCodec()

Method that can be called to determine if a custom ObjectCodec is needed for binding data parsed using JsonParser constructed by this factory (which typically also implies the same for serialization with JsonGenerator).

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

version

public abstract Version version()

Accessor for getting version of the core package, given a parser instance. Left for sub-classes to implement.

Specified by:

version in interface Versioned

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 feature JsonParser.Feature.AUTO_CLOSE_SOURCE is enabled. Whether parser owns the input source depends on factory method that was used to construct instance (so check JsonFactory for details, but the general idea is that if caller passes in closable resource (such as InputStream or Reader) parser does NOT own the source; but if it passes a reference (such as File or URL and creates stream or reader it does own them.

Specified by:

close in interface Closeable

Throws:

IOException

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

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

enable

public JsonParser enable(JsonParser.Feature f)

Method for enabling specified parser feature (check JsonParser.Feature for list of features)

disable

public JsonParser disable(JsonParser.Feature f)

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

configure

public JsonParser configure(JsonParser.Feature f,
                            boolean state)

Method for enabling or disabling specified feature (check JsonParser.Feature for list of features)

isEnabled

public boolean isEnabled(JsonParser.Feature f)

Method for checking whether specified JsonParser.Feature is enabled.

getFeatureMask

public int getFeatureMask()

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

Returns:

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

Since:

2.3

setFeatureMask

@Deprecated
public JsonParser setFeatureMask(int mask)

Deprecated. Since 2.7, use overrideStdFeatures(int, int) instead

Bulk set method for (re)setting states of all standard JsonParser.Features

Returns:

This parser object, to allow chaining of calls

Since:

2.3

overrideStdFeatures

public JsonParser overrideStdFeatures(int values,
                                      int mask)

Bulk set method for (re)setting states of features specified by mask. Functionally equivalent to int 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 change

mask - Bit mask of features to change

Since:

2.6

getFormatFeatures

public int getFormatFeatures()

Bulk access method for getting state of all FormatFeatures, format-specific on/off configuration settings.

Returns:

Bit mask that defines current states of all standard FormatFeatures.

Since:

2.6

overrideFormatFeatures

public JsonParser overrideFormatFeatures(int values,
                                         int mask)

Bulk set method for (re)setting states of FormatFeatures, 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 FormatFeatures.

Parameters:

values - Bit mask of set/clear state for features to change

mask - Bit mask of features to change

Since:

2.6

nextToken

public abstract JsonToken nextToken()
                             throws IOException,
                                    JsonParseException

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

JsonParseException

nextValue

public abstract JsonToken nextValue()
                             throws IOException,
                                    JsonParseException

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 if JsonToken.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 calling getCurrentName() 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

JsonParseException

nextFieldName

public boolean nextFieldName(SerializableString str)
                      throws IOException,
                             JsonParseException

Method that fetches next token (as if calling nextToken()) and verifies whether it is JsonToken.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 is JsonToken.FIELD_NAME)

Throws:

IOException

JsonParseException

nextFieldName

public String nextFieldName()
                     throws IOException,
                            JsonParseException

Method that fetches next token (as if calling nextToken()) and verifies whether it is JsonToken.FIELD_NAME; if it is, returns same as getCurrentName(), otherwise null.

Throws:

IOException

JsonParseException

Since:

2.5

nextTextValue

public String nextTextValue()
                     throws IOException,
                            JsonParseException

Method that fetches next token (as if calling nextToken()) and if it is JsonToken.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

JsonParseException

nextIntValue

public int nextIntValue(int defaultValue)
                 throws IOException,
                        JsonParseException

Method that fetches next token (as if calling nextToken()) and if it is JsonToken.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 a String value next from input.

Throws:

IOException

JsonParseException

nextLongValue

public long nextLongValue(long defaultValue)
                   throws IOException,
                          JsonParseException

Method that fetches next token (as if calling nextToken()) and if it is JsonToken.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 String value next from input.

Throws:

IOException

JsonParseException

nextBooleanValue

public Boolean nextBooleanValue()
                         throws IOException,
                                JsonParseException

Method that fetches next token (as if calling nextToken()) and if it is JsonToken.VALUE_TRUE or JsonToken.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 String value next from input.

Throws:

IOException

JsonParseException

skipChildren

public abstract JsonParser skipChildren()
                                 throws IOException,
                                        JsonParseException

Method that will skip all child tokens of an array or object token that the parser currently points to, iff stream points to JsonToken.START_OBJECT or JsonToken.START_ARRAY. If not, it will do nothing. After skipping, stream will point to matching JsonToken.END_OBJECT or JsonToken.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 call nextToken() to point to the next available token, if any.

Throws:

IOException

JsonParseException

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 calling nextToken() (and the underlying stream may be closed). Closing may be due to an explicit call to close() or because parser has encountered end of input.

getCurrentToken

public abstract JsonToken getCurrentToken()

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.

getCurrentTokenId

public abstract int getCurrentTokenId()

Method similar to getCurrentToken() but that returns an int instead of JsonToken (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 from JsonTokenId.

Since:

2.3

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 for parser.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 from nextToken(), or the token has been consumed)

hasTokenId

public abstract boolean hasTokenId(int id)

Method that is functionally equivalent to: return getCurrentTokenId() == 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 getCurrentTokenId() == 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:

2.6

getCurrentName

public abstract String getCurrentName()
                               throws IOException

Method that can be called to get the name associated with the current token: for JsonToken.FIELD_NAMEs it will be the same as what getText() returns; for field values it will be preceding field name; and for others (array values, root-level values) null.

Throws:

IOException

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.

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.

getCurrentLocation

public abstract JsonLocation getCurrentLocation()

Method that returns location of the last processed character; usually for error reporting purposes.

isExpectedStartArrayToken

public boolean isExpectedStartArrayToken()

Specialized accessor that can be used to verify that the current token indicates start array (usually meaning that current token is JsonToken.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:

   getCurrentToken() == 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 to isExpectedStartArrayToken(), but checks whether stream currently points to JsonToken.START_OBJECT.

Since:

2.5

clearCurrentToken

public abstract void clearCurrentToken()

Method called to "consume" the current token by effectively removing it so that hasCurrentToken() returns false, and getCurrentToken() null). Cleared token value can still be accessed by calling getLastClearedToken() (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 using clearCurrentToken(). 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.

getText

public abstract String getText()
                        throws IOException

Method for accessing textual representation of the current token; if no current token (before first call to nextToken(), or after encountering end-of-input), returns null. Method can be called for any token type.

Throws:

IOException

getTextCharacters

public abstract char[] getTextCharacters()
                                  throws IOException

Method similar to getText(), 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

getTextLength

public abstract int getTextLength()
                           throws IOException

Accessor used with getTextCharacters(), 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 with getTextCharacters(), 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 of getTextCharacters() 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 type JsonToken.VALUE_NUMBER_INT or JsonToken.VALUE_NUMBER_FLOAT, returns one of JsonParser.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 type JsonToken.VALUE_NUMBER_INT and it can be expressed as a value of Java byte primitive type. It can also be called for JsonToken.VALUE_NUMBER_FLOAT; if so, it is equivalent to calling getDoubleValue() 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 type JsonToken.VALUE_NUMBER_INT and it can be expressed as a value of Java short primitive type. It can also be called for JsonToken.VALUE_NUMBER_FLOAT; if so, it is equivalent to calling getDoubleValue() 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 type JsonToken.VALUE_NUMBER_INT and it can be expressed as a value of Java int primitive type. It can also be called for JsonToken.VALUE_NUMBER_FLOAT; if so, it is equivalent to calling getDoubleValue() 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 type JsonToken.VALUE_NUMBER_INT and it can be expressed as a Java long primitive type. It can also be called for JsonToken.VALUE_NUMBER_FLOAT; if so, it is equivalent to calling getDoubleValue() 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 type JsonToken.VALUE_NUMBER_INT and it can not be used as a Java long primitive type due to its magnitude. It can also be called for JsonToken.VALUE_NUMBER_FLOAT; if so, it is equivalent to calling getDecimalValue() and then constructing a BigInteger from that value.

Throws:

IOException

getFloatValue

public abstract float getFloatValue()
                             throws IOException

Numeric accessor that can be called when the current token is of type JsonToken.VALUE_NUMBER_FLOAT and it can be expressed as a Java float primitive type. It can also be called for JsonToken.VALUE_NUMBER_INT; if so, it is equivalent to calling getLongValue() 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 type JsonToken.VALUE_NUMBER_FLOAT and it can be expressed as a Java double primitive type. It can also be called for JsonToken.VALUE_NUMBER_INT; if so, it is equivalent to calling getLongValue() 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 type JsonToken.VALUE_NUMBER_FLOAT or JsonToken.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 is JsonToken.VALUE_TRUE or JsonToken.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 abstract Object getEmbeddedObject()
                                  throws IOException

Accessor that can be called if (and only if) the current token is JsonToken.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).

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 via getText() 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 (see Base64Variants for definitions of "standard" variants).

Returns:

Decoded binary data

Throws:

IOException

getBinaryValue

public byte[] getBinaryValue()
                      throws IOException

Convenience alternative to getBinaryValue(Base64Variant) that defaults to using Base64Variants.getDefaultVariant() as the default encoding.

Throws:

IOException

readBinaryValue

public int readBinaryValue(OutputStream out)
                    throws IOException

Method that can be used as an alternative to getBigIntegerValue(), especially when value can be large. The main difference (beyond method of returning content using OutputStream 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 to readBinaryValue(OutputStream) but allows explicitly specifying base64 variant to use.

Parameters:

bv - base64 variant to use

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

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 an int (including structured type markers like start/end Object/Array) default value of 0 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 an int (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 integer parsing rules.

If representation can not be converted to an int (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 integer parsing rules.

If representation can not be converted to an int (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 a String. 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 a String. 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 with canReadObjectId() 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 with canReadTypeId() 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 (like Boolean). Note: method can only be called if the parser has an object codec assigned; this is true for parsers constructed by MappingJsonFactory (from "jackson-databind" jar) but not for JsonFactory (unless its setCodec 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 or Map. 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 by MappingJsonFactory (defined in 'jackson-databind' bundle) but not for JsonFactory (unless its setCodec 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<?> 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 root TreeNode 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

_codec

protected ObjectCodec _codec()

_constructError

protected JsonParseException _constructError(String msg)

Helper method for constructing JsonParseExceptions based on current state of the parser

_reportUnsupportedOperation

protected void _reportUnsupportedOperation()

Helper method to call for operations that are not supported by parser implementation.

Since:

2.1