Module tools.jackson.core

Package tools.jackson.core.util

Class JsonParserSequence

java.lang.Object

tools.jackson.core.JsonParser

tools.jackson.core.util.JsonParserDelegate

tools.jackson.core.util.JsonParserSequence

All Implemented Interfaces:

Closeable, AutoCloseable, Versioned

public class JsonParserSequence
extends JsonParserDelegate

Helper class that can be used to sequence multiple physical JsonParsers to create a single logical sequence of tokens, as a single JsonParser.

Fairly simple use of JsonParserDelegate: only need to override nextToken() to handle transition

Nested Class Summary

Nested classes/interfaces inherited from class tools.jackson.core.JsonParser

JsonParser.NumberType, JsonParser.NumberTypeFP

Field Summary

Fields

Modifier and Type	Field	Description
protected final boolean	_checkForExistingToken	Configuration that determines whether state of parsers is first verified to see if parser already points to a token (that is, JsonParser.hasCurrentToken() returns true), and if so that token is first return before JsonParser.nextToken() is called.
protected boolean	_hasToken	Flag used to indicate that `JsonParser.nextToken()` should not be called, due to parser already pointing to a token.
protected int	_nextParserIndex	Index of the next parser in _parsers.
protected final JsonParser[]	_parsers	Parsers other than the first one (which is initially assigned as delegate)

Fields inherited from class tools.jackson.core.util.JsonParserDelegate

delegate

Fields inherited from class tools.jackson.core.JsonParser

DEFAULT_READ_CAPABILITIES

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	JsonParserSequence(boolean checkForExistingToken, JsonParser[] parsers)

Method Summary

Modifier and Type	Method	Description
protected void	addFlattenedActiveParsers(List<JsonParser> listToAddIn)
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 StreamReadFeature.AUTO_CLOSE_SOURCE is enabled.
int	containedParsersCount()	Method that is most useful for debugging or testing; returns actual number of underlying parsers sequence was constructed with (nor just ones remaining active)
static JsonParserSequence	createFlattened(boolean checkForExistingToken, JsonParser first, JsonParser second)	Method that will construct a sequence (possibly a sequence) that contains all given sub-parsers.
String	nextName()	Method that fetches next token (as if calling JsonParser.nextToken()) and verifies whether it is JsonToken.PROPERTY_NAME; if it is, returns same as JsonParser.currentName(), otherwise null.
boolean	nextName(SerializableString str)	Method that fetches next token (as if calling JsonParser.nextToken()) and verifies whether it is JsonToken.PROPERTY_NAME with specified name and returns result of that comparison.
int	nextNameMatch(PropertyNameMatcher matcher)	Method that tries to match next token from stream as JsonToken.PROPERTY_NAME, and if so, further match it to one of pre-specified (field) names.
JsonToken	nextToken()	Main iteration method, which will advance stream enough to determine type of the next token, if any.
JsonParser	skipChildren()	Need to override, re-implement similar to how method defined in ParserMinimalBase, to keep state correct here.
protected JsonToken	switchAndReturnNext()
protected boolean	switchToNext()	Method that will switch active delegate parser from the current one to the next parser in sequence, if there is another parser left: if so, the next parser will become the active delegate parser.

Methods inherited from class tools.jackson.core.util.JsonParserDelegate

assignCurrentValue, canParseAsync, canReadObjectId, canReadTypeId, clearCurrentToken, currentLocation, currentName, currentNameMatch, currentToken, currentTokenCount, currentTokenId, currentTokenLocation, currentValue, delegate, finishToken, getBigIntegerValue, getBinaryValue, getBooleanValue, getByteValue, getDecimalValue, getDoubleValue, getEmbeddedObject, getFloatValue, getIntValue, getLastClearedToken, getLongValue, getNumberType, getNumberTypeFP, getNumberValue, getNumberValueDeferred, getNumberValueExact, getObjectId, getSchema, getShortValue, getString, getString, getStringCharacters, getStringLength, getStringOffset, getTypeId, getValueAsBoolean, getValueAsBoolean, getValueAsDouble, getValueAsDouble, getValueAsInt, getValueAsInt, getValueAsLong, getValueAsLong, getValueAsString, getValueAsString, hasCurrentToken, hasStringCharacters, hasToken, hasTokenId, isClosed, isEnabled, isExpectedNumberIntToken, isExpectedStartArrayToken, isExpectedStartObjectToken, isNaN, nextValue, nonBlockingInputFeeder, objectReadContext, readBinaryValue, readValueAs, readValueAs, readValueAs, readValueAsTree, streamReadCapabilities, streamReadConstraints, streamReadContext, streamReadFeatures, streamReadInputSource, version

Methods inherited from class tools.jackson.core.JsonParser

_constructReadException, _constructReadException, _constructReadException, _constructReadException, _constructReadException, _constructReadException, _reportUnsupportedOperation, getBinaryValue, getText, getTextCharacters, getTextLength, getTextOffset, nextBooleanValue, nextIntValue, nextLongValue, nextStringValue, readBinaryValue, releaseBuffered, releaseBuffered

Methods inherited from class java.lang.Object

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

Field Details

_parsers

protected final JsonParser[] _parsers

Parsers other than the first one (which is initially assigned as delegate)

_checkForExistingToken

protected final boolean _checkForExistingToken

Configuration that determines whether state of parsers is first verified to see if parser already points to a token (that is, JsonParser.hasCurrentToken() returns true), and if so that token is first return before JsonParser.nextToken() is called. If enabled, this check is made; if disabled, no check is made and JsonParser.nextToken() is always called for all parsers.

Default setting is false (for backwards-compatibility) so that possible existing token is not considered for parsers.

_nextParserIndex

protected int _nextParserIndex

Index of the next parser in _parsers.

_hasToken

protected boolean _hasToken

Flag used to indicate that `JsonParser.nextToken()` should not be called, due to parser already pointing to a token.

Constructor Details

JsonParserSequence

protected JsonParserSequence(boolean checkForExistingToken,
 JsonParser[] parsers)

Method Details

createFlattened

public static JsonParserSequence createFlattened(boolean checkForExistingToken,
 JsonParser first,
 JsonParser second)

Method that will construct a sequence (possibly a sequence) that contains all given sub-parsers. All parsers given are checked to see if they are sequences: and if so, they will be "flattened", that is, contained parsers are directly added in a new sequence instead of adding sequences within sequences. This is done to minimize delegation depth, ideally only having just a single level of delegation.

Parameters:

checkForExistingToken - Flag passed to be assigned as _checkForExistingToken for resulting sequence

first - First parser to traverse

second - Second parser to traverse

Returns:

Sequence instance constructed

addFlattenedActiveParsers

protected void addFlattenedActiveParsers(List<JsonParser> listToAddIn)

close

public void close()
           throws JacksonException

Description copied from class: JsonParser

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 StreamReadFeature.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 AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class JsonParserDelegate

Throws:

JacksonException

nextToken

public JsonToken nextToken()
                    throws JacksonException

Description copied from class: JsonParser

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.

Overrides:

nextToken in class JsonParserDelegate

Returns:

Next token from the stream, if any found, or null to indicate end-of-input

Throws:

JacksonException - for low-level read issues

StreamReadException - for decoding problems

skipChildren

public JsonParser skipChildren()
                        throws JacksonException

Need to override, re-implement similar to how method defined in ParserMinimalBase, to keep state correct here.

Overrides:

skipChildren in class JsonParserDelegate

Returns:

This parser, to allow call chaining

Throws:

JacksonException - for low-level read issues

StreamReadException - for decoding problems

nextName

public String nextName()
                throws JacksonException

Description copied from class: JsonParser

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

NOTE: in Jackson 2.x method was called nextFieldName()

Overrides:

nextName in class JsonParserDelegate

Returns:

Name of the the JsonToken.PROPERTY_NAME parser advanced to, if any; null if next token is of some other type

Throws:

JacksonException - for low-level read issues

StreamReadException - for decoding problems

nextName

public boolean nextName(SerializableString str)
                 throws JacksonException

Description copied from class: JsonParser

Method that fetches next token (as if calling JsonParser.nextToken()) and verifies whether it is JsonToken.PROPERTY_NAME with specified name and returns result of that comparison. It is functionally equivalent to:

  return (nextToken() == JsonToken.PROPERTY_NAME) && str.getValue().equals(currentName());

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.

NOTE: in Jackson 2.x method was called nextFieldName()

Overrides:

nextName in class JsonParserDelegate

Parameters:

str - Property name to compare next token to (if next token is JsonToken.PROPERTY_NAME)

Returns:

True if parser advanced to JsonToken.PROPERTY_NAME with specified name; false otherwise (different token or non-matching name)

Throws:

JacksonException - for low-level read issues

StreamReadException - for decoding problems

nextNameMatch

public int nextNameMatch(PropertyNameMatcher matcher)
                  throws JacksonException

Description copied from class: JsonParser

Method that tries to match next token from stream as JsonToken.PROPERTY_NAME, and if so, further match it to one of pre-specified (field) names. If match succeeds, property index (non-negative `int`) is returned; otherwise one of marker constants from PropertyNameMatcher.

Overrides:

nextNameMatch in class JsonParserDelegate

Parameters:

matcher - Matcher that will handle actual matching

Returns:

Index of the matched property name, if non-negative, or a negative error code otherwise (see PropertyNameMatcher for details)

Throws:

JacksonIOException - for low-level read issues

StreamReadException - for decoding problems

JacksonException

containedParsersCount

public int containedParsersCount()

Method that is most useful for debugging or testing; returns actual number of underlying parsers sequence was constructed with (nor just ones remaining active)

Returns:

Number of actual underlying parsers this sequence has

switchToNext

protected boolean switchToNext()

Method that will switch active delegate parser from the current one to the next parser in sequence, if there is another parser left: if so, the next parser will become the active delegate parser.

Returns:

True if switch succeeded; false otherwise

switchAndReturnNext

protected JsonToken switchAndReturnNext()
                                 throws JacksonException

Throws:

JacksonException