Package com.fasterxml.jackson.core.filter

Class FilteringParserDelegate

  • All Implemented Interfaces:
    Versioned, java.io.Closeable, java.lang.AutoCloseable
    public class FilteringParserDelegate
extends JsonParserDelegate
    Specialized JsonParserDelegate that allows use of TokenFilter for outputting a subset of content that is visible to caller
    Since:
    2.6

    • Constructor Detail

      • FilteringParserDelegate

        @Deprecated
public FilteringParserDelegate​(JsonParser p,
                               TokenFilter f,
                               boolean includePath,
                               boolean allowMultipleMatches)
        Deprecated.

      • FilteringParserDelegate

        public FilteringParserDelegate​(JsonParser p,
                               TokenFilter f,
                               TokenFilter.Inclusion inclusion,
                               boolean allowMultipleMatches)
        Parameters:
        p - Parser to delegate calls to
        f - Filter to use
        inclusion - Definition of inclusion criteria
        allowMultipleMatches - Whether to allow multiple matches

    • Method Detail

      • getMatchCount

        public int getMatchCount()
        Accessor for finding number of matches, where specific token and sub-tree starting (if structured type) are passed.
        Returns:
        Number of matches

      • currentToken

        public JsonToken currentToken()
        Description copied from class: JsonParser
        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.
        Overrides:
        currentToken in class JsonParserDelegate
        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.

      • currentTokenId

        public final int currentTokenId()
        Description copied from class: JsonParser
        Method similar to JsonParser.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.

        Overrides:
        currentTokenId in class JsonParserDelegate
        Returns:
        int matching one of constants from JsonTokenId.

      • hasCurrentToken

        public boolean hasCurrentToken()
        Description copied from class: JsonParser
        Method for checking whether parser currently points to a token (and data for that token is available). Equivalent to check for parser.getCurrentToken() != null.
        Overrides:
        hasCurrentToken in class JsonParserDelegate
        Returns:
        True if the parser just returned a valid token via JsonParser.nextToken(); false otherwise (parser was just constructed, encountered end-of-input and returned null from JsonParser.nextToken(), or the token has been consumed)

      • hasTokenId

        public boolean hasTokenId​(int id)
        Description copied from class: JsonParser
        Method that is functionally equivalent to: return currentTokenId() == id but may be more efficiently implemented.

        Note that no traversal or conversion is performed; so in some cases calling method like JsonParser.isExpectedStartArrayToken() is necessary instead.

        Overrides:
        hasTokenId in class JsonParserDelegate
        Parameters:
        id - Token id to match (from (@link JsonTokenId})
        Returns:
        True if the parser current points to specified token

      • hasToken

        public final boolean hasToken​(JsonToken t)
        Description copied from class: JsonParser
        Method that is functionally equivalent to: return currentToken() == t but may be more efficiently implemented.

        Note that no traversal or conversion is performed; so in some cases calling method like JsonParser.isExpectedStartArrayToken() is necessary instead.

        Overrides:
        hasToken in class JsonParserDelegate
        Parameters:
        t - Token to match
        Returns:
        True if the parser current points to specified token

      • isExpectedStartArrayToken

        public boolean isExpectedStartArrayToken()
        Description copied from class: JsonParser
        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: 

           currentToken() == JsonToken.START_ARRAY
        but may be overridden by custom parser implementations.
        Overrides:
        isExpectedStartArrayToken in class JsonParserDelegate
        Returns:
        True if the current token can be considered as a start-array marker (such JsonToken.START_ARRAY); false if not

      • getParsingContext

        public JsonStreamContext getParsingContext()
        Description copied from class: JsonParser
        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.
        Overrides:
        getParsingContext in class JsonParserDelegate
        Returns:
        Stream input context (JsonStreamContext) associated with this parser

      • currentName

        public java.lang.String currentName()
                             throws java.io.IOException
        Description copied from class: JsonParser
        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 JsonParser.getText() returns; for field values it will be preceding field name; and for others (array values, root-level values) null.
        Overrides:
        currentName in class JsonParserDelegate
        Returns:
        Name of the current field in the parsing context
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getLastClearedToken

        public JsonToken getLastClearedToken()
        Description copied from class: JsonParser
        Method that can be called to get the last token that was cleared using JsonParser.clearCurrentToken(). This is not necessarily the latest token read. Will return null if no tokens have been cleared, or if parser has been closed.
        Overrides:
        getLastClearedToken in class JsonParserDelegate
        Returns:
        Last cleared token, if any; null otherwise

      • overrideCurrentName

        public void overrideCurrentName​(java.lang.String name)
        Description copied from class: JsonParser
        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.

        Overrides:
        overrideCurrentName in class JsonParserDelegate
        Parameters:
        name - Name to use as the current name; may be null.

      • nextToken

        public JsonToken nextToken()
                    throws java.io.IOException
        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:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • nextValue

        public JsonToken nextValue()
                    throws java.io.IOException
        Description copied from class: JsonParser
        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 JsonParser.getCurrentName() when parser points to the value.
        Overrides:
        nextValue in class JsonParserDelegate
        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:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • skipChildren

        public JsonParser skipChildren()
                        throws java.io.IOException
        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:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • hasTextCharacters

        public boolean hasTextCharacters()
        Description copied from class: JsonParser
        Method that can be used to determine whether calling of JsonParser.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.

        Overrides:
        hasTextCharacters in class JsonParserDelegate
        Returns:
        True if parser currently has character array that can be efficiently returned via JsonParser.getTextCharacters(); false means that it may or may not exist

      • getTextCharacters

        public char[] getTextCharacters()
                         throws java.io.IOException
        Description copied from class: JsonParser
        Method similar to JsonParser.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 JsonParser.getTextOffset()) to know the actual offset
        • Length of textual contents may be less than the length of returned buffer: call JsonParser.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 JsonParser.getText()) is to avoid construction of a String object (which will make a copy of contents).

        Overrides:
        getTextCharacters in class JsonParserDelegate
        Returns:
        Buffer that contains the current textual value (but not necessarily at offset 0, and not necessarily until the end of buffer)
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems, including if the text is too large, see StreamReadConstraints.Builder.maxStringLength(int)

      • getBigIntegerValue

        public java.math.BigInteger getBigIntegerValue()
                                        throws java.io.IOException
        Description copied from class: JsonParser
        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 JsonParser.getDecimalValue() and then constructing a BigInteger from that value.
        Overrides:
        getBigIntegerValue in class JsonParserDelegate
        Returns:
        Current number value as BigInteger (if numeric token); otherwise exception thrown
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getByteValue

        public byte getByteValue()
                  throws java.io.IOException
        Description copied from class: JsonParser
        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. Note that in addition to "natural" input range of [-128, 127], this also allows "unsigned 8-bit byte" values [128, 255]: but for this range value will be translated by truncation, leading to sign change.

        It can also be called for JsonToken.VALUE_NUMBER_FLOAT; if so, it is equivalent to calling JsonParser.getDoubleValue() and then casting; except for possible overflow/underflow exception.

        Note: if the resulting integer value falls outside range of [-128, 255], a InputCoercionException will be thrown to indicate numeric overflow/underflow.

        Overrides:
        getByteValue in class JsonParserDelegate
        Returns:
        Current number value as byte (if numeric token within range of [-128, 255]); otherwise exception thrown
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getShortValue

        public short getShortValue()
                    throws java.io.IOException
        Description copied from class: JsonParser
        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 JsonParser.getDoubleValue() and then casting; except for possible overflow/underflow exception.

        Note: if the resulting integer value falls outside range of Java short, a InputCoercionException will be thrown to indicate numeric overflow/underflow.

        Overrides:
        getShortValue in class JsonParserDelegate
        Returns:
        Current number value as short (if numeric token within Java 16-bit signed short range); otherwise exception thrown
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getDoubleValue

        public double getDoubleValue()
                      throws java.io.IOException
        Description copied from class: JsonParser
        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 JsonParser.getLongValue() and then casting; except for possible overflow/underflow exception.

        Note: if the value falls outside of range of Java double, a InputCoercionException will be thrown to indicate numeric overflow/underflow.

        Overrides:
        getDoubleValue in class JsonParserDelegate
        Returns:
        Current number value as double (if numeric token within Java double range); otherwise exception thrown
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getFloatValue

        public float getFloatValue()
                    throws java.io.IOException
        Description copied from class: JsonParser
        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 JsonParser.getLongValue() and then casting; except for possible overflow/underflow exception.

        Note: if the value falls outside of range of Java float, a InputCoercionException will be thrown to indicate numeric overflow/underflow.

        Overrides:
        getFloatValue in class JsonParserDelegate
        Returns:
        Current number value as float (if numeric token within Java float range); otherwise exception thrown
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getIntValue

        public int getIntValue()
                throws java.io.IOException
        Description copied from class: JsonParser
        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 JsonParser.getDoubleValue() and then casting; except for possible overflow/underflow exception.

        Note: if the resulting integer value falls outside range of Java int, a InputCoercionException may be thrown to indicate numeric overflow/underflow.

        Overrides:
        getIntValue in class JsonParserDelegate
        Returns:
        Current number value as int (if numeric token within Java 32-bit signed int range); otherwise exception thrown
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getLongValue

        public long getLongValue()
                  throws java.io.IOException
        Description copied from class: JsonParser
        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 JsonParser.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 InputCoercionException may be thrown to indicate numeric overflow/underflow.

        Overrides:
        getLongValue in class JsonParserDelegate
        Returns:
        Current number value as long (if numeric token within Java 32-bit signed long range); otherwise exception thrown
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getNumberValue

        public java.lang.Number getNumberValue()
                                throws java.io.IOException
        Description copied from class: JsonParser
        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.
        Overrides:
        getNumberValue in class JsonParserDelegate
        Returns:
        Numeric value of the current token in its most optimal representation
        Throws:
        java.io.IOException - Problem with access: JsonParseException if the current token is not numeric, or if decoding of the value fails (invalid format for numbers); plain IOException if underlying content read fails (possible if values are extracted lazily)

      • getValueAsInt

        public int getValueAsInt()
                  throws java.io.IOException
        Description copied from class: JsonParser
        Method that will try to convert value of current token to a Java int value. 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.

        Overrides:
        getValueAsInt in class JsonParserDelegate
        Returns:
        int value current token is converted to, if possible; exception thrown otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getValueAsInt

        public int getValueAsInt​(int defaultValue)
                  throws java.io.IOException
        Description copied from class: JsonParser
        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.

        Overrides:
        getValueAsInt in class JsonParserDelegate
        Parameters:
        defaultValue - Default value to return if conversion to int is not possible
        Returns:
        int value current token is converted to, if possible; def otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getValueAsLong

        public long getValueAsLong()
                    throws java.io.IOException
        Description copied from class: JsonParser
        Method that will try to convert value of current token to a long. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.

        If representation can not be converted to a long (including structured type markers like start/end Object/Array) default value of 0L will be returned; no exceptions are thrown.

        Overrides:
        getValueAsLong in class JsonParserDelegate
        Returns:
        long value current token is converted to, if possible; exception thrown otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getValueAsLong

        public long getValueAsLong​(long defaultValue)
                    throws java.io.IOException
        Description copied from class: JsonParser
        Method that will try to convert value of current token to a long. Numbers are coerced using default Java rules; booleans convert to 0 (false) and 1 (true), and Strings are parsed using default Java language integer parsing rules.

        If representation can not be converted to a long (including structured type markers like start/end Object/Array) specified def will be returned; no exceptions are thrown.

        Overrides:
        getValueAsLong in class JsonParserDelegate
        Parameters:
        defaultValue - Default value to return if conversion to long is not possible
        Returns:
        long value current token is converted to, if possible; def otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getValueAsDouble

        public double getValueAsDouble()
                        throws java.io.IOException
        Description copied from class: JsonParser
        Method that will try to convert value of current token to a Java double. Numbers are coerced using default Java rules; booleans convert to 0.0 (false) and 1.0 (true), and Strings are parsed using default Java language floating point parsing rules.

        If representation can not be converted to a double (including structured types like Objects and Arrays), default value of 0.0 will be returned; no exceptions are thrown.

        Overrides:
        getValueAsDouble in class JsonParserDelegate
        Returns:
        double value current token is converted to, if possible; exception thrown otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getValueAsDouble

        public double getValueAsDouble​(double defaultValue)
                        throws java.io.IOException
        Description copied from class: JsonParser
        Method that will try to convert value of current token to a Java double. Numbers are coerced using default Java rules; booleans convert to 0.0 (false) and 1.0 (true), and Strings are parsed using default Java language floating point parsing rules.

        If representation can not be converted to a double (including structured types like Objects and Arrays), specified def will be returned; no exceptions are thrown.

        Overrides:
        getValueAsDouble in class JsonParserDelegate
        Parameters:
        defaultValue - Default value to return if conversion to double is not possible
        Returns:
        double value current token is converted to, if possible; def otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getValueAsBoolean

        public boolean getValueAsBoolean()
                          throws java.io.IOException
        Description copied from class: JsonParser
        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.

        Overrides:
        getValueAsBoolean in class JsonParserDelegate
        Returns:
        boolean value current token is converted to, if possible; exception thrown otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getValueAsBoolean

        public boolean getValueAsBoolean​(boolean defaultValue)
                          throws java.io.IOException
        Description copied from class: JsonParser
        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.

        Overrides:
        getValueAsBoolean in class JsonParserDelegate
        Parameters:
        defaultValue - Default value to return if conversion to boolean is not possible
        Returns:
        boolean value current token is converted to, if possible; def otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getValueAsString

        public java.lang.String getValueAsString()
                                  throws java.io.IOException
        Description copied from class: JsonParser
        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.
        Overrides:
        getValueAsString in class JsonParserDelegate
        Returns:
        String value current token is converted to, if possible; null otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getValueAsString

        public java.lang.String getValueAsString​(java.lang.String defaultValue)
                                  throws java.io.IOException
        Description copied from class: JsonParser
        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.
        Overrides:
        getValueAsString in class JsonParserDelegate
        Parameters:
        defaultValue - Default value to return if conversion to String is not possible
        Returns:
        String value current token is converted to, if possible; def otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getEmbeddedObject

        public java.lang.Object getEmbeddedObject()
                                   throws java.io.IOException
        Description copied from class: JsonParser
        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). One exception is access to binary content (whether via base64 encoding or not) which typically is accessible using this method, as well as JsonParser.getBinaryValue().

        Overrides:
        getEmbeddedObject in class JsonParserDelegate
        Returns:
        Embedded value (usually of "native" type supported by format) for the current token, if any; null otherwise
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • getBinaryValue

        public byte[] getBinaryValue​(Base64Variant b64variant)
                      throws java.io.IOException
        Description copied from class: JsonParser
        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 JsonParser.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.

        Overrides:
        getBinaryValue in class JsonParserDelegate
        Parameters:
        b64variant - Expected variant of base64 encoded content (see Base64Variants for definitions of "standard" variants).
        Returns:
        Decoded binary data
        Throws:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems

      • readBinaryValue

        public int readBinaryValue​(Base64Variant b64variant,
                           java.io.OutputStream out)
                    throws java.io.IOException
        Description copied from class: JsonParser
        Similar to JsonParser.readBinaryValue(OutputStream) but allows explicitly specifying base64 variant to use.
        Overrides:
        readBinaryValue in class JsonParserDelegate
        Parameters:
        b64variant - 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:
        java.io.IOException - for low-level read issues, or JsonParseException for decoding problems