com.fasterxml.jackson.core

## Class JsonParser

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

- 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 a `JsonFactory` instance.
  Author:
    Tatu Saloranta

- - ### Nested Class Summary

    Nested Classes
    Modifier and Type | Class and 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.

  - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `protected int` | `_features` Bit flag composed of bits that indicate which `JsonParser.Feature`s are enabled.

  - ### Constructor Summary

    Constructors
    Modifier | Constructor and Description
    --- | ---
    `protected` | `JsonParser()`
    `protected` | `JsonParser(int features)`

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `protected ObjectCodec` | `_codec()`
    `protected JsonParseException` | `_constructError(String msg)` Helper method for constructing `JsonParseException`s 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_NAME`s 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.Feature`s.
    `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 `FormatFeature`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 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 `FormatFeature`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 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)` Bulk set method for (re)setting states of all standard `JsonParser.Feature`s
    `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.Feature`s 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();`
      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`
      Specified by:
        `close` in interface `AutoCloseable`
      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.Feature`s.
      Returns:
        Bit mask that defines current states of all standard `JsonParser.Feature`s.
      Since:
        2.3

    - #### setFeatureMask

          public JsonParser setFeatureMask(int mask)

      Bulk set method for (re)setting states of all standard `JsonParser.Feature`s
      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);`
      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 `FormatFeature`s, format-specific on/off configuration settings.
      Returns:
        Bit mask that defines current states of all standard `FormatFeature`s.
      Since:
        2.6

    - #### overrideFormatFeatures

          public JsonParser overrideFormatFeatures(int values,
                                          int mask)

      Bulk set method for (re)setting states of `FormatFeature`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 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_NAME`s 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 `JsonParseException`s 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

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