Class JsonGenerator

  • All Implemented Interfaces:
    java.io.Closeable, java.lang.AutoCloseable, Versioned
    Direct Known Subclasses:
    JsonGeneratorBase, JsonGeneratorDelegate, TokenBuffer

    public abstract class JsonGenerator
    extends java.lang.Object
    implements java.io.Closeable, Versioned
    Base class that defines public API for writing JSON content. Instances are created using factory methods of a JsonFactory instance.
    Author:
    Tatu Saloranta
    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description
      static class  JsonGenerator.Feature
      Enumeration that defines all togglable features for generators.
    • Field Summary

      Fields 
      Modifier and Type Field Description
      protected PrettyPrinter _cfgPrettyPrinter
      Object that handles pretty-printing (usually additional white space to make results more human-readable) during output.
    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      protected JsonGenerator()  
    • Method Summary

      All Methods Instance Methods Abstract Methods Concrete Methods Deprecated Methods 
      Modifier and Type Method Description
      boolean canUseSchema​(FormatSchema schema)
      Method that can be used to verify that given schema can be used with this generator (using setSchema(org.codehaus.jackson.FormatSchema)).
      abstract void close()
      Method called to close this generator, so that no more content can be written.
      JsonGenerator configure​(JsonGenerator.Feature f, boolean state)
      Method for enabling or disabling specified feature: check JsonGenerator.Feature for list of available features.
      abstract void copyCurrentEvent​(JsonParser jp)
      Method for copying contents of the current event that the given parser instance points to.
      abstract void copyCurrentStructure​(JsonParser jp)
      Method for copying contents of the current event and following events that it encloses the given parser instance points to.
      abstract JsonGenerator disable​(JsonGenerator.Feature f)
      Method for disabling specified features (check JsonGenerator.Feature for list of features)
      void disableFeature​(JsonGenerator.Feature f)
      abstract JsonGenerator enable​(JsonGenerator.Feature f)
      Method for enabling specified parser features: check JsonGenerator.Feature for list of available features.
      void enableFeature​(JsonGenerator.Feature f)
      abstract void flush()
      Method called to flush any buffered content to the underlying target (output stream, writer), and to flush the target itself as well.
      CharacterEscapes getCharacterEscapes()
      Method for accessing custom escapes factory uses for JsonGenerators it creates.
      abstract ObjectCodec getCodec()
      Method for accessing the object used for writing Java object as Json content (using method writeObject(java.lang.Object)).
      int getHighestEscapedChar()
      Accessor method for testing what is the highest unescaped character configured for this generator.
      abstract JsonStreamContext getOutputContext()  
      java.lang.Object getOutputTarget()
      Method that can be used to get access to object that is used as target for generated output; this is usually either OutputStream or Writer, depending on what generator was constructed with.
      abstract boolean isClosed()
      Method that can be called to determine whether this generator is closed or not.
      abstract boolean isEnabled​(JsonGenerator.Feature f)
      Method for checking whether given feature is enabled.
      boolean isFeatureEnabled​(JsonGenerator.Feature f)
      JsonGenerator setCharacterEscapes​(CharacterEscapes esc)
      Method for defining custom escapes factory uses for JsonGenerators it creates.
      abstract JsonGenerator setCodec​(ObjectCodec oc)
      Method that can be called to set or reset the object to use for writing Java objects as JsonContent (using method writeObject(java.lang.Object)).
      void setFeature​(JsonGenerator.Feature f, boolean state)
      JsonGenerator setHighestNonEscapedChar​(int charCode)
      Method that can be called to request that generator escapes all character codes above specified code point (if positive value); or, to not escape any characters except for ones that must be escaped for the data format (if -1).
      JsonGenerator setPrettyPrinter​(PrettyPrinter pp)
      Method for setting a custom pretty printer, which is usually used to add indentation for improved human readability.
      void setSchema​(FormatSchema schema)
      Method to call to make this generator use specified schema.
      abstract JsonGenerator useDefaultPrettyPrinter()
      Convenience method for enabling pretty-printing using the default pretty printer (DefaultPrettyPrinter).
      Version version()
      Method called to detect version of the component that implements this interface; returned version should never be null, but may return specific "not available" instance (see Version for details).
      void writeArrayFieldStart​(java.lang.String fieldName)
      Convenience method for outputting a field entry ("member") (that will contain a JSON Array value), and the START_ARRAY marker.
      void writeBinary​(byte[] data)
      Similar to writeBinary(Base64Variant,byte[],int,int), but assumes default to using the Jackson default Base64 variant (which is Base64Variants.MIME_NO_LINEFEEDS).
      void writeBinary​(byte[] data, int offset, int len)
      Similar to writeBinary(Base64Variant,byte[],int,int), but default to using the Jackson default Base64 variant (which is Base64Variants.MIME_NO_LINEFEEDS).
      abstract void writeBinary​(Base64Variant b64variant, byte[] data, int offset, int len)
      Method that will output given chunk of binary data as base64 encoded, as a complete String value (surrounded by double quotes).
      void writeBinaryField​(java.lang.String fieldName, byte[] data)
      Convenience method for outputting a field entry ("member") that contains specified data in base64-encoded form.
      abstract void writeBoolean​(boolean state)
      Method for outputting literal Json boolean value (one of Strings 'true' and 'false').
      void writeBooleanField​(java.lang.String fieldName, boolean value)
      Convenience method for outputting a field entry ("member") that has a boolean value.
      abstract void writeEndArray()
      Method for writing closing marker of a JSON Array value (character ']'; plus possible white space decoration if pretty-printing is enabled).
      abstract void writeEndObject()
      Method for writing closing marker of a JSON Object value (character '}'; plus possible white space decoration if pretty-printing is enabled).
      abstract void writeFieldName​(java.lang.String name)
      Method for writing a field name (JSON String surrounded by double quotes: syntactically identical to a JSON String value), possibly decorated by white space if pretty-printing is enabled.
      void writeFieldName​(SerializedString name)
      Method similar to writeFieldName(String), main difference being that it may perform better as some of processing (such as quoting of certain characters, or encoding into external encoding if supported by generator) can be done just once and reused for later calls.
      void writeFieldName​(SerializableString name)
      Method similar to writeFieldName(String), main difference being that it may perform better as some of processing (such as quoting of certain characters, or encoding into external encoding if supported by generator) can be done just once and reused for later calls.
      abstract void writeNull()
      Method for outputting literal Json null value.
      void writeNullField​(java.lang.String fieldName)
      Convenience method for outputting a field entry ("member") that has JSON literal value null.
      abstract void writeNumber​(double d)
      Method for outputting indicate Json numeric value.
      abstract void writeNumber​(float f)
      Method for outputting indicate Json numeric value.
      abstract void writeNumber​(int v)
      Method for outputting given value as Json number.
      abstract void writeNumber​(long v)
      Method for outputting given value as Json number.
      abstract void writeNumber​(java.lang.String encodedValue)
      Write method that can be used for custom numeric types that can not be (easily?) converted to "standard" Java number types.
      abstract void writeNumber​(java.math.BigDecimal dec)
      Method for outputting indicate Json numeric value.
      abstract void writeNumber​(java.math.BigInteger v)
      Method for outputting given value as Json number.
      void writeNumberField​(java.lang.String fieldName, double value)
      Convenience method for outputting a field entry ("member") that has the specified numeric value.
      void writeNumberField​(java.lang.String fieldName, float value)
      Convenience method for outputting a field entry ("member") that has the specified numeric value.
      void writeNumberField​(java.lang.String fieldName, int value)
      Convenience method for outputting a field entry ("member") that has the specified numeric value.
      void writeNumberField​(java.lang.String fieldName, long value)
      Convenience method for outputting a field entry ("member") that has the specified numeric value.
      void writeNumberField​(java.lang.String fieldName, java.math.BigDecimal value)
      Convenience method for outputting a field entry ("member") that has the specified numeric value.
      abstract void writeObject​(java.lang.Object pojo)
      Method for writing given Java object (POJO) as Json.
      void writeObjectField​(java.lang.String fieldName, java.lang.Object pojo)
      Convenience method for outputting a field entry ("member") that has contents of specific Java object as its value.
      void writeObjectFieldStart​(java.lang.String fieldName)
      Convenience method for outputting a field entry ("member") (that will contain a JSON Object value), and the START_OBJECT marker.
      abstract void writeRaw​(char c)
      Method that will force generator to copy input text verbatim with no modifications (including that no escaping is done and no separators are added even if context [array, object] would otherwise require such).
      abstract void writeRaw​(char[] text, int offset, int len)
      Method that will force generator to copy input text verbatim with no modifications (including that no escaping is done and no separators are added even if context [array, object] would otherwise require such).
      abstract void writeRaw​(java.lang.String text)
      Method that will force generator to copy input text verbatim with no modifications (including that no escaping is done and no separators are added even if context [array, object] would otherwise require such).
      abstract void writeRaw​(java.lang.String text, int offset, int len)
      Method that will force generator to copy input text verbatim with no modifications (including that no escaping is done and no separators are added even if context [array, object] would otherwise require such).
      abstract void writeRawUTF8String​(byte[] text, int offset, int length)
      Method similar to writeString(String) but that takes as its input a UTF-8 encoded String that is to be output as-is, without additional escaping (type of which depends on data format; backslashes for JSON).
      abstract void writeRawValue​(char[] text, int offset, int len)  
      abstract void writeRawValue​(java.lang.String text)
      Method that will force generator to copy input text verbatim without any modifications, but assuming it must constitute a single legal JSON value (number, string, boolean, null, Array or List).
      abstract void writeRawValue​(java.lang.String text, int offset, int len)  
      abstract void writeStartArray()
      Method for writing starting marker of a JSON Array value (character '['; plus possible white space decoration if pretty-printing is enabled).
      abstract void writeStartObject()
      Method for writing starting marker of a JSON Object value (character '{'; plus possible white space decoration if pretty-printing is enabled).
      abstract void writeString​(char[] text, int offset, int len)
      Method for outputting a String value.
      abstract void writeString​(java.lang.String text)
      Method for outputting a String value.
      void writeString​(SerializableString text)
      Method similar to writeString(String), but that takes SerializableString which can make this potentially more efficient to call as generator may be able to reuse quoted and/or encoded representation.
      void writeStringField​(java.lang.String fieldName, java.lang.String value)
      Convenience method for outputting a field entry ("member") that has a String value.
      abstract void writeTree​(JsonNode rootNode)
      Method for writing given JSON tree (expressed as a tree where given JsonNode is the root) using this generator.
      abstract void writeUTF8String​(byte[] text, int offset, int length)
      Method similar to writeString(String) but that takes as its input a UTF-8 encoded String which has not been escaped using whatever escaping scheme data format requires (for JSON that is backslash-escaping for control characters and double-quotes; for other formats something else).
      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    • Field Detail

      • _cfgPrettyPrinter

        protected PrettyPrinter _cfgPrettyPrinter
        Object that handles pretty-printing (usually additional white space to make results more human-readable) during output. If null, no pretty-printing is done.
    • Constructor Detail

      • JsonGenerator

        protected JsonGenerator()
    • Method Detail

      • setSchema

        public void setSchema​(FormatSchema schema)
        Method to call to make this generator use specified schema. Method must be called before generating any content, right after instance has been created. Note that not all generators support schemas; and those that do usually only accept specific types of schemas: ones defined for data format this generator produces.

        If generator does not support specified schema, UnsupportedOperationException is thrown.

        Parameters:
        schema - Schema to use
        Throws:
        java.lang.UnsupportedOperationException - if generator does not support schema
        Since:
        1.8
      • canUseSchema

        public boolean canUseSchema​(FormatSchema schema)
        Method that can be used to verify that given schema can be used with this generator (using setSchema(org.codehaus.jackson.FormatSchema)).
        Parameters:
        schema - Schema to check
        Returns:
        True if this generator can use given schema; false if not
        Since:
        1.8
      • version

        public Version version()
        Description copied from interface: Versioned
        Method called to detect version of the component that implements this interface; returned version should never be null, but may return specific "not available" instance (see Version for details).
        Specified by:
        version in interface Versioned
        Since:
        1.6
      • getOutputTarget

        public java.lang.Object getOutputTarget()
        Method that can be used to get access to object that is used as target for generated output; this is usually either OutputStream or Writer, depending on what generator was constructed with. Note that returned value may be null in some cases; including case where implementation does not want to exposed raw source to caller. In cases where output has been decorated, object returned here is the decorated version; this allows some level of interaction between users of generator 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.

        Since:
        1.8
      • setCodec

        public abstract JsonGenerator setCodec​(ObjectCodec oc)
        Method that can be called to set or reset the object to use for writing Java objects as JsonContent (using method writeObject(java.lang.Object)).
        Returns:
        Generator itself (this), to allow chaining
      • setPrettyPrinter

        public JsonGenerator setPrettyPrinter​(PrettyPrinter pp)
        Method for setting a custom pretty printer, which is usually used to add indentation for improved human readability. By default, generator does not do pretty printing.

        To use the default pretty printer that comes with core Jackson distribution, call useDefaultPrettyPrinter() instead.

        Returns:
        Generator itself (this), to allow chaining
      • useDefaultPrettyPrinter

        public abstract JsonGenerator useDefaultPrettyPrinter()
        Convenience method for enabling pretty-printing using the default pretty printer (DefaultPrettyPrinter).
        Returns:
        Generator itself (this), to allow chaining
      • setHighestNonEscapedChar

        public JsonGenerator setHighestNonEscapedChar​(int charCode)
        Method that can be called to request that generator escapes all character codes above specified code point (if positive value); or, to not escape any characters except for ones that must be escaped for the data format (if -1). To force escaping of all non-ASCII characters, for example, this method would be called with value of 127.

        Note that generators are NOT required to support setting of value higher than 127, because there are other ways to affect quoting (or lack thereof) of character codes between 0 and 127. Not all generators support concept of escaping, either; if so, calling this method will have no effect.

        Default implementation does nothing; sub-classes need to redefine it according to rules of supported data format.

        Parameters:
        charCode - Either -1 to indicate that no additional escaping is to be done; or highest code point not to escape (meaning higher ones will be), if positive value.
        Since:
        1.8
      • getHighestEscapedChar

        public int getHighestEscapedChar()
        Accessor method for testing what is the highest unescaped character configured for this generator. This may be either positive value (when escaping configuration has been set and is in effect), or 0 to indicate that no additional escaping is in effect. Some generators may not support additional escaping: for example, generators for binary formats that do not use escaping should simply return 0.
        Returns:
        Currently active limitation for highest non-escaped character, if defined; or -1 to indicate no additional escaping is performed.
      • getCharacterEscapes

        public CharacterEscapes getCharacterEscapes()
        Method for accessing custom escapes factory uses for JsonGenerators it creates.
        Since:
        1.8
      • writeStartArray

        public abstract void writeStartArray()
                                      throws java.io.IOException,
                                             JsonGenerationException
        Method for writing starting marker of a JSON Array value (character '['; plus possible white space decoration if pretty-printing is enabled).

        Array values can be written in any context where values are allowed: meaning everywhere except for when a field name is expected.

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeEndArray

        public abstract void writeEndArray()
                                    throws java.io.IOException,
                                           JsonGenerationException
        Method for writing closing marker of a JSON Array value (character ']'; plus possible white space decoration if pretty-printing is enabled).

        Marker can be written if the innermost structured type is Array.

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeStartObject

        public abstract void writeStartObject()
                                       throws java.io.IOException,
                                              JsonGenerationException
        Method for writing starting marker of a JSON Object value (character '{'; plus possible white space decoration if pretty-printing is enabled).

        Object values can be written in any context where values are allowed: meaning everywhere except for when a field name is expected.

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeEndObject

        public abstract void writeEndObject()
                                     throws java.io.IOException,
                                            JsonGenerationException
        Method for writing closing marker of a JSON Object value (character '}'; plus possible white space decoration if pretty-printing is enabled).

        Marker can be written if the innermost structured type is Object, and the last written event was either a complete value, or START-OBJECT marker (see JSON specification for more details).

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeFieldName

        public abstract void writeFieldName​(java.lang.String name)
                                     throws java.io.IOException,
                                            JsonGenerationException
        Method for writing a field name (JSON String surrounded by double quotes: syntactically identical to a JSON String value), possibly decorated by white space if pretty-printing is enabled.

        Field names can only be written in Object context (check out JSON specification for details), when field name is expected (field names alternate with values).

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeFieldName

        public void writeFieldName​(SerializedString name)
                            throws java.io.IOException,
                                   JsonGenerationException
        Method similar to writeFieldName(String), main difference being that it may perform better as some of processing (such as quoting of certain characters, or encoding into external encoding if supported by generator) can be done just once and reused for later calls.

        Default implementation simple uses unprocessed name container in serialized String; implementations are strongly encouraged to make use of more efficient methods argument object has.

        Throws:
        java.io.IOException
        JsonGenerationException
        Since:
        1.6
      • writeFieldName

        public void writeFieldName​(SerializableString name)
                            throws java.io.IOException,
                                   JsonGenerationException
        Method similar to writeFieldName(String), main difference being that it may perform better as some of processing (such as quoting of certain characters, or encoding into external encoding if supported by generator) can be done just once and reused for later calls.

        Default implementation simple uses unprocessed name container in serialized String; implementations are strongly encouraged to make use of more efficient methods argument object has.

        Throws:
        java.io.IOException
        JsonGenerationException
        Since:
        1.7
      • writeString

        public abstract void writeString​(java.lang.String text)
                                  throws java.io.IOException,
                                         JsonGenerationException
        Method for outputting a String value. Depending on context this means either array element, (object) field value or a stand alone String; but in all cases, String will be surrounded in double quotes, and contents will be properly escaped as required by JSON specification.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeString

        public abstract void writeString​(char[] text,
                                         int offset,
                                         int len)
                                  throws java.io.IOException,
                                         JsonGenerationException
        Method for outputting a String value. Depending on context this means either array element, (object) field value or a stand alone String; but in all cases, String will be surrounded in double quotes, and contents will be properly escaped as required by JSON specification.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeRawUTF8String

        public abstract void writeRawUTF8String​(byte[] text,
                                                int offset,
                                                int length)
                                         throws java.io.IOException,
                                                JsonGenerationException
        Method similar to writeString(String) but that takes as its input a UTF-8 encoded String that is to be output as-is, without additional escaping (type of which depends on data format; backslashes for JSON). However, quoting that data format requires (like double-quotes for JSON) will be added around the value if and as necessary.

        Note that some backends may choose not to support this method: for example, if underlying destination is a Writer using this method would require UTF-8 decoding. If so, implementation may instead choose to throw a UnsupportedOperationException due to ineffectiveness of having to decode input.

        Throws:
        java.io.IOException
        JsonGenerationException
        Since:
        1.7
      • writeUTF8String

        public abstract void writeUTF8String​(byte[] text,
                                             int offset,
                                             int length)
                                      throws java.io.IOException,
                                             JsonGenerationException
        Method similar to writeString(String) but that takes as its input a UTF-8 encoded String which has not been escaped using whatever escaping scheme data format requires (for JSON that is backslash-escaping for control characters and double-quotes; for other formats something else). This means that textual JSON backends need to check if value needs JSON escaping, but otherwise can just be copied as is to output. Also, quoting that data format requires (like double-quotes for JSON) will be added around the value if and as necessary.

        Note that some backends may choose not to support this method: for example, if underlying destination is a Writer using this method would require UTF-8 decoding. In this case generator implementation may instead choose to throw a UnsupportedOperationException due to ineffectiveness of having to decode input.

        Throws:
        java.io.IOException
        JsonGenerationException
        Since:
        1.7
      • writeRaw

        public abstract void writeRaw​(java.lang.String text)
                               throws java.io.IOException,
                                      JsonGenerationException
        Method that will force generator to copy input text verbatim with no modifications (including that no escaping is done and no separators are added even if context [array, object] would otherwise require such). If such separators are desired, use writeRawValue(String) instead.

        Note that not all generator implementations necessarily support such by-pass methods: those that do not will throw UnsupportedOperationException.

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeRaw

        public abstract void writeRaw​(java.lang.String text,
                                      int offset,
                                      int len)
                               throws java.io.IOException,
                                      JsonGenerationException
        Method that will force generator to copy input text verbatim with no modifications (including that no escaping is done and no separators are added even if context [array, object] would otherwise require such). If such separators are desired, use writeRawValue(String) instead.

        Note that not all generator implementations necessarily support such by-pass methods: those that do not will throw UnsupportedOperationException.

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeRaw

        public abstract void writeRaw​(char[] text,
                                      int offset,
                                      int len)
                               throws java.io.IOException,
                                      JsonGenerationException
        Method that will force generator to copy input text verbatim with no modifications (including that no escaping is done and no separators are added even if context [array, object] would otherwise require such). If such separators are desired, use writeRawValue(String) instead.

        Note that not all generator implementations necessarily support such by-pass methods: those that do not will throw UnsupportedOperationException.

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeRaw

        public abstract void writeRaw​(char c)
                               throws java.io.IOException,
                                      JsonGenerationException
        Method that will force generator to copy input text verbatim with no modifications (including that no escaping is done and no separators are added even if context [array, object] would otherwise require such). If such separators are desired, use writeRawValue(String) instead.

        Note that not all generator implementations necessarily support such by-pass methods: those that do not will throw UnsupportedOperationException.

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeRawValue

        public abstract void writeRawValue​(java.lang.String text)
                                    throws java.io.IOException,
                                           JsonGenerationException
        Method that will force generator to copy input text verbatim without any modifications, but assuming it must constitute a single legal JSON value (number, string, boolean, null, Array or List). Assuming this, proper separators are added if and as needed (comma or colon), and generator state updated to reflect this.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeBinary

        public abstract void writeBinary​(Base64Variant b64variant,
                                         byte[] data,
                                         int offset,
                                         int len)
                                  throws java.io.IOException,
                                         JsonGenerationException
        Method that will output given chunk of binary data as base64 encoded, as a complete String value (surrounded by double quotes). This method defaults

        Note: because Json Strings can not contain unescaped linefeeds, if linefeeds are included (as per last argument), they must be escaped. This adds overhead for decoding without improving readability. Alternatively if linefeeds are not included, resulting String value may violate the requirement of base64 RFC which mandates line-length of 76 characters and use of linefeeds. However, all JsonParser implementations are required to accept such "long line base64"; as do typical production-level base64 decoders.

        Parameters:
        b64variant - Base64 variant to use: defines details such as whether padding is used (and if so, using which character); what is the maximum line length before adding linefeed, and also the underlying alphabet to use.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumber

        public abstract void writeNumber​(int v)
                                  throws java.io.IOException,
                                         JsonGenerationException
        Method for outputting given value as Json number. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumber

        public abstract void writeNumber​(long v)
                                  throws java.io.IOException,
                                         JsonGenerationException
        Method for outputting given value as Json number. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumber

        public abstract void writeNumber​(java.math.BigInteger v)
                                  throws java.io.IOException,
                                         JsonGenerationException
        Method for outputting given value as Json number. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumber

        public abstract void writeNumber​(double d)
                                  throws java.io.IOException,
                                         JsonGenerationException
        Method for outputting indicate Json numeric value. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumber

        public abstract void writeNumber​(float f)
                                  throws java.io.IOException,
                                         JsonGenerationException
        Method for outputting indicate Json numeric value. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumber

        public abstract void writeNumber​(java.math.BigDecimal dec)
                                  throws java.io.IOException,
                                         JsonGenerationException
        Method for outputting indicate Json numeric value. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumber

        public abstract void writeNumber​(java.lang.String encodedValue)
                                  throws java.io.IOException,
                                         JsonGenerationException,
                                         java.lang.UnsupportedOperationException
        Write method that can be used for custom numeric types that can not be (easily?) converted to "standard" Java number types. Because numbers are not surrounded by double quotes, regular writeString(java.lang.String) method can not be used; nor writeRaw(java.lang.String) because that does not properly handle value separators needed in Array or Object contexts.

        Note: because of lack of type safety, some generator implementations may not be able to implement this method. For example, if a binary json format is used, it may require type information for encoding; similarly for generator-wrappers around Java objects or Json nodes. If implementation does not implement this method, it needs to throw UnsupportedOperationException.

        Throws:
        java.io.IOException
        JsonGenerationException
        java.lang.UnsupportedOperationException
      • writeBoolean

        public abstract void writeBoolean​(boolean state)
                                   throws java.io.IOException,
                                          JsonGenerationException
        Method for outputting literal Json boolean value (one of Strings 'true' and 'false'). Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNull

        public abstract void writeNull()
                                throws java.io.IOException,
                                       JsonGenerationException
        Method for outputting literal Json null value. Can be called in any context where a value is expected (Array value, Object field value, root-level value). Additional white space may be added around the value if pretty-printing is enabled.
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeObject

        public abstract void writeObject​(java.lang.Object pojo)
                                  throws java.io.IOException,
                                         JsonProcessingException
        Method for writing given Java object (POJO) as Json. Exactly how the object gets written depends on object in question (ad on codec, its configuration); for most beans it will result in Json object, but for others Json array, or String or numeric value (and for nulls, Json null literal. NOTE: generator must have its object codec set to non-null value; for generators created by a mapping factory this is the case, for others not.
        Throws:
        java.io.IOException
        JsonProcessingException
      • writeTree

        public abstract void writeTree​(JsonNode rootNode)
                                throws java.io.IOException,
                                       JsonProcessingException
        Method for writing given JSON tree (expressed as a tree where given JsonNode is the root) using this generator. This will generally just call writeObject(java.lang.Object) with given node, but is added for convenience and to make code more explicit in cases where it deals specifically with trees.
        Throws:
        java.io.IOException
        JsonProcessingException
      • writeStringField

        public void writeStringField​(java.lang.String fieldName,
                                     java.lang.String value)
                              throws java.io.IOException,
                                     JsonGenerationException
        Convenience method for outputting a field entry ("member") that has a String value. Equivalent to:
          writeFieldName(fieldName);
          writeString(value);
        

        Note: many performance-sensitive implementations override this method

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeBooleanField

        public final void writeBooleanField​(java.lang.String fieldName,
                                            boolean value)
                                     throws java.io.IOException,
                                            JsonGenerationException
        Convenience method for outputting a field entry ("member") that has a boolean value. Equivalent to:
          writeFieldName(fieldName);
          writeBoolean(value);
        
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNullField

        public final void writeNullField​(java.lang.String fieldName)
                                  throws java.io.IOException,
                                         JsonGenerationException
        Convenience method for outputting a field entry ("member") that has JSON literal value null. Equivalent to:
          writeFieldName(fieldName);
          writeNull();
        
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumberField

        public final void writeNumberField​(java.lang.String fieldName,
                                           int value)
                                    throws java.io.IOException,
                                           JsonGenerationException
        Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:
          writeFieldName(fieldName);
          writeNumber(value);
        
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumberField

        public final void writeNumberField​(java.lang.String fieldName,
                                           long value)
                                    throws java.io.IOException,
                                           JsonGenerationException
        Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:
          writeFieldName(fieldName);
          writeNumber(value);
        
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumberField

        public final void writeNumberField​(java.lang.String fieldName,
                                           double value)
                                    throws java.io.IOException,
                                           JsonGenerationException
        Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:
          writeFieldName(fieldName);
          writeNumber(value);
        
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumberField

        public final void writeNumberField​(java.lang.String fieldName,
                                           float value)
                                    throws java.io.IOException,
                                           JsonGenerationException
        Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:
          writeFieldName(fieldName);
          writeNumber(value);
        
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeNumberField

        public final void writeNumberField​(java.lang.String fieldName,
                                           java.math.BigDecimal value)
                                    throws java.io.IOException,
                                           JsonGenerationException
        Convenience method for outputting a field entry ("member") that has the specified numeric value. Equivalent to:
          writeFieldName(fieldName);
          writeNumber(value);
        
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeBinaryField

        public final void writeBinaryField​(java.lang.String fieldName,
                                           byte[] data)
                                    throws java.io.IOException,
                                           JsonGenerationException
        Convenience method for outputting a field entry ("member") that contains specified data in base64-encoded form. Equivalent to:
          writeFieldName(fieldName);
          writeBinary(value);
        
        Throws:
        java.io.IOException
        JsonGenerationException
      • writeArrayFieldStart

        public final void writeArrayFieldStart​(java.lang.String fieldName)
                                        throws java.io.IOException,
                                               JsonGenerationException
        Convenience method for outputting a field entry ("member") (that will contain a JSON Array value), and the START_ARRAY marker. Equivalent to:
          writeFieldName(fieldName);
          writeStartArray();
        

        Note: caller still has to take care to close the array (by calling {#link #writeEndArray}) after writing all values of the value Array.

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeObjectFieldStart

        public final void writeObjectFieldStart​(java.lang.String fieldName)
                                         throws java.io.IOException,
                                                JsonGenerationException
        Convenience method for outputting a field entry ("member") (that will contain a JSON Object value), and the START_OBJECT marker. Equivalent to:
          writeFieldName(fieldName);
          writeStartObject();
        

        Note: caller still has to take care to close the Object (by calling {#link #writeEndObject}) after writing all entries of the value Object.

        Throws:
        java.io.IOException
        JsonGenerationException
      • writeObjectField

        public final void writeObjectField​(java.lang.String fieldName,
                                           java.lang.Object pojo)
                                    throws java.io.IOException,
                                           JsonProcessingException
        Convenience method for outputting a field entry ("member") that has contents of specific Java object as its value. Equivalent to:
          writeFieldName(fieldName);
          writeObject(pojo);
        
        Throws:
        java.io.IOException
        JsonProcessingException
      • copyCurrentEvent

        public abstract void copyCurrentEvent​(JsonParser jp)
                                       throws java.io.IOException,
                                              JsonProcessingException
        Method for copying contents of the current event that the given parser instance points to. Note that the method will not copy any other events, such as events contained within Json Array or Object structures.

        Calling this method will not advance the given parser, although it may cause parser to internally process more data (if it lazy loads contents of value events, for example)

        Throws:
        java.io.IOException
        JsonProcessingException
      • copyCurrentStructure

        public abstract void copyCurrentStructure​(JsonParser jp)
                                           throws java.io.IOException,
                                                  JsonProcessingException
        Method for copying contents of the current event and following events that it encloses the given parser instance points to.

        So what constitutes enclosing? Here is the list of events that have associated enclosed events that will get copied:

        After calling this method, parser will point to the last event that was copied. This will either be the event parser already pointed to (if there were no enclosed events), or the last enclosed event copied.

        Throws:
        java.io.IOException
        JsonProcessingException
      • getOutputContext

        public abstract JsonStreamContext getOutputContext()
        Returns:
        Context object that can give information about logical position within generated json content.
      • flush

        public abstract void flush()
                            throws java.io.IOException
        Method called to flush any buffered content to the underlying target (output stream, writer), and to flush the target itself as well.
        Throws:
        java.io.IOException
      • isClosed

        public abstract boolean isClosed()
        Method that can be called to determine whether this generator is closed or not. If it is closed, no more output can be done.
      • close

        public abstract void close()
                            throws java.io.IOException
        Method called to close this generator, so that no more content can be written.

        Whether the underlying target (stream, writer) gets closed depends on whether this generator either manages the target (i.e. is the only one with access to the target -- case if caller passes a reference to the resource such as File, but not stream); or has feature JsonGenerator.Feature.AUTO_CLOSE_TARGET enabled. If either of above is true, the target is also closed. Otherwise (not managing, feature not enabled), target is not closed.

        Specified by:
        close in interface java.lang.AutoCloseable
        Specified by:
        close in interface java.io.Closeable
        Throws:
        java.io.IOException