/* Jackson JSON-processor.
*
* Copyright (c) 2007- Tatu Saloranta, tatu.saloranta@iki.fi
*
* Licensed under the License specified in file LICENSE, included with
* the source code and binary code bundles.
* You may not use this file except in compliance with the License.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.fasterxml.jackson.core;
import java.io.*;
import java.math.BigDecimal;
import java.math.BigInteger;
import com.fasterxml.jackson.core.io.CharacterEscapes;
/**
* Base class that defines public API for writing JSON content.
* Instances are created using factory methods of
* a {@link JsonFactory} instance.
*
* @author Tatu Saloranta
*/
public abstract class JsonGenerator
implements Closeable, Flushable, // as of 2.1
Versioned
{
/**
* Enumeration that defines all togglable features for generators.
*/
public enum Feature {
/**
* Feature that determines whether generator will automatically
* close underlying output target that is NOT owned by the
* generator.
* If disabled, calling application has to separately
* close the underlying {@link OutputStream} and {@link Writer}
* instances used to create the generator. If enabled, generator
* will handle closing, as long as generator itself gets closed:
* this happens when end-of-input is encountered, or generator
* is closed by a call to {@link JsonGenerator#close}.
*<p>
* Feature is enabled by default.
*/
AUTO_CLOSE_TARGET(true),
/**
* Feature that determines what happens when the generator is
* closed while there are still unmatched
* {@link JsonToken#START_ARRAY} or {@link JsonToken#START_OBJECT}
* entries in output content. If enabled, such Array(s) and/or
* Object(s) are automatically closed; if disabled, nothing
* specific is done.
*<p>
* Feature is enabled by default.
*/
AUTO_CLOSE_JSON_CONTENT(true),
/**
* Feature that determines whether JSON Object field names are
* quoted using double-quotes, as specified by JSON specification
* or not. Ability to disable quoting was added to support use
* cases where they are not usually expected, which most commonly
* occurs when used straight from Javascript.
*<p>
* Feature is enabled by default (since it is required by JSON specification).
*/
QUOTE_FIELD_NAMES(true),
/**
* Feature that determines whether "exceptional" (not real number)
* float/double values are output as quoted strings.
* The values checked are Double.Nan,
* Double.POSITIVE_INFINITY and Double.NEGATIVE_INIFINTY (and
* associated Float values).
* If feature is disabled, these numbers are still output using
* associated literal values, resulting in non-conformant
* output.
*<p>
* Feature is enabled by default.
*/
QUOTE_NON_NUMERIC_NUMBERS(true),
/**
* Feature that forces all Java numbers to be written as JSON strings.
* Default state is 'false', meaning that Java numbers are to
* be serialized using basic numeric serialization (as JSON
* numbers, integral or floating point). If enabled, all such
* numeric values are instead written out as JSON Strings.
*<p>
* One use case is to avoid problems with Javascript limitations:
* since Javascript standard specifies that all number handling
* should be done using 64-bit IEEE 754 floating point values,
* result being that some 64-bit integer values can not be
* accurately represent (as mantissa is only 51 bit wide).
*<p>
* Feature is disabled by default.
*/
WRITE_NUMBERS_AS_STRINGS(false),
/**
* Feature that specifies that calls to {@link #flush} will cause
* matching <code>flush()</code> to underlying {@link OutputStream}
* or {@link Writer}; if disabled this will not be done.
* Main reason to disable this feature is to prevent flushing at
* generator level, if it is not possible to prevent method being
* called by other code (like <code>ObjectMapper</code> or third
* party libraries).
*<p>
* Feature is enabled by default.
*/
FLUSH_PASSED_TO_STREAM(true),
/**
* Feature that specifies that all characters beyond 7-bit ASCII
* range (i.e. code points of 128 and above) need to be output
* using format-specific escapes (for JSON, backslash escapes),
* if format uses escaping mechanisms (which is generally true
* for textual formats but not for binary formats).
*<p>
* Feature is disabled by default.
*/
ESCAPE_NON_ASCII(false),
;
private final boolean _defaultState;
private final int _mask;
/**
* Method that calculates bit set (flags) of all features that
* are enabled by default.
*/
public static int collectDefaults()
{
int flags = 0;
for (Feature f : values()) {
if (f.enabledByDefault()) {
flags |= f.getMask();
}
}
return flags;
}
private Feature(boolean defaultState) {
_mask = (1 << ordinal());
_defaultState = defaultState;
}
public boolean enabledByDefault() { return _defaultState; }
public int getMask() { return _mask; }
}
/*
/**********************************************************
/* Configuration
/**********************************************************
*/
/**
* Object that handles pretty-printing (usually additional
* white space to make results more human-readable) during
* output. If null, no pretty-printing is done.
*/
protected PrettyPrinter _cfgPrettyPrinter;
/*
/**********************************************************
/* Construction, configuration, initialization
/**********************************************************
*/
protected JsonGenerator() { }
/**
* 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.
*<p>
* If generator does not support specified schema, {@link UnsupportedOperationException}
* is thrown.
*
* @param schema Schema to use
*
* @throws UnsupportedOperationException if generator does not support schema
*/
public void setSchema(FormatSchema schema)
{
throw new UnsupportedOperationException("Generator of type "+getClass().getName()+" does not support schema of type '"
+schema.getSchemaType()+"'");
}
/**
* Method for accessing Schema that this parser uses, if any.
* Default implementation returns null.
*
* @since 2.1
*/
public FormatSchema getSchema() {
return null;
}
/**
* Method that can be used to verify that given schema can be used with
* this generator (using {@link #setSchema}).
*
* @param schema Schema to check
*
* @return True if this generator can use given schema; false if not
*/
public boolean canUseSchema(FormatSchema schema) {
return false;
}
/**
* Accessor for finding out version of the bundle that provided this generator instance.
*/
// @Override
public abstract Version version();
/**
* Method that can be used to get access to object that is used
* as target for generated output; this is usually either
* {@link OutputStream} or {@link 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.
*<p>
* In general use of this accessor should be considered as
* "last effort", i.e. only used if no other mechanism is applicable.
*/
public Object getOutputTarget() {
return null;
}
/**
* Method that allows overriding String used for separating root-level
* JSON values (default is single space character)
*
* @param sep Separator to use, if any; null means that no separator is
* automatically added
*
* @since 2.1
*/
public JsonGenerator setRootValueSeparator(SerializableString sep) {
throw new UnsupportedOperationException();
}
/*
/**********************************************************
/* Public API, configuration
/**********************************************************
*/
/**
* Method for enabling specified parser features:
* check {@link Feature} for list of available features.
*
* @return Generator itself (this), to allow chaining
*/
public abstract JsonGenerator enable(Feature f);
/**
* Method for disabling specified features
* (check {@link Feature} for list of features)
*
* @return Generator itself (this), to allow chaining
*/
public abstract JsonGenerator disable(Feature f);
/**
* Method for enabling or disabling specified feature:
* check {@link Feature} for list of available features.
*
* @return Generator itself (this), to allow chaining
*/
public final JsonGenerator configure(Feature f, boolean state)
{
if (state) {
enable(f);
} else {
disable(f);
}
return this;
}
/**
* Method for checking whether given feature is enabled.
* Check {@link Feature} for list of available features.
*/
public abstract boolean isEnabled(Feature f);
/**
* Method that can be called to set or reset the object to
* use for writing Java objects as JsonContent
* (using method {@link #writeObject}).
*
* @return Generator itself (this), to allow chaining
*/
public abstract JsonGenerator setCodec(ObjectCodec oc);
/**
* Method for accessing the object used for writing Java
* object as Json content
* (using method {@link #writeObject}).
*/
public abstract ObjectCodec getCodec();
/*
/**********************************************************
/* Configuring generator
/**********************************************************
*/
/**
* 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.
*<p>
* To use the default pretty printer that comes with core
* Jackson distribution, call {@link #useDefaultPrettyPrinter}
* instead.
*
* @return Generator itself (this), to allow chaining
*/
public JsonGenerator setPrettyPrinter(PrettyPrinter pp) {
_cfgPrettyPrinter = pp;
return this;
}
/**
* Accessor for checking whether this generator has a configured
* {@link PrettyPrinter}; returns it if so, null if none configured.
*
* @since 2.1
*/
public PrettyPrinter getPrettyPrinter() {
return _cfgPrettyPrinter;
}
/**
* Convenience method for enabling pretty-printing using
* the default pretty printer
* ({@link com.fasterxml.jackson.core.util.DefaultPrettyPrinter}).
*
* @return Generator itself (this), to allow chaining
*/
public abstract JsonGenerator useDefaultPrettyPrinter();
/**
* 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.
*<p>
* 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.
*<p>
* Default implementation does nothing; sub-classes need to redefine
* it according to rules of supported data format.
*
* @param 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.
*/
public JsonGenerator setHighestNonEscapedChar(int charCode) {
return this;
}
/**
* 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.
*
* @return Currently active limitation for highest non-escaped character,
* if defined; or -1 to indicate no additional escaping is performed.
*/
public int getHighestEscapedChar() {
return 0;
}
/**
* Method for accessing custom escapes factory uses for {@link JsonGenerator}s
* it creates.
*/
public CharacterEscapes getCharacterEscapes() {
return null;
}
/**
* Method for defining custom escapes factory uses for {@link JsonGenerator}s
* it creates.
*/
public JsonGenerator setCharacterEscapes(CharacterEscapes esc) {
return this;
}
/*
/**********************************************************
/* Public API, write methods, structural
/**********************************************************
*/
/**
* Method for writing starting marker of a JSON Array value
* (character '['; plus possible white space decoration
* if pretty-printing is enabled).
*<p>
* Array values can be written in any context where values
* are allowed: meaning everywhere except for when
* a field name is expected.
*/
public abstract void writeStartArray()
throws IOException, JsonGenerationException;
/**
* Method for writing closing marker of a JSON Array value
* (character ']'; plus possible white space decoration
* if pretty-printing is enabled).
*<p>
* Marker can be written if the innermost structured type
* is Array.
*/
public abstract void writeEndArray()
throws IOException, JsonGenerationException;
/**
* Method for writing starting marker of a JSON Object value
* (character '{'; plus possible white space decoration
* if pretty-printing is enabled).
*<p>
* Object values can be written in any context where values
* are allowed: meaning everywhere except for when
* a field name is expected.
*/
public abstract void writeStartObject()
throws IOException, JsonGenerationException;
/**
* Method for writing closing marker of a JSON Object value
* (character '}'; plus possible white space decoration
* if pretty-printing is enabled).
*<p>
* 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).
*/
public abstract void writeEndObject()
throws 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.
*<p>
* 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).
*/
public abstract void writeFieldName(String name)
throws IOException, JsonGenerationException;
/**
* Method similar to {@link #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.
*<p>
* Default implementation simple uses unprocessed name container in
* serialized String; implementations are strongly encouraged to make
* use of more efficient methods argument object has.
*/
public abstract void writeFieldName(SerializableString name)
throws IOException, JsonGenerationException;
/*
/**********************************************************
/* Public API, write methods, text/String values
/**********************************************************
*/
/**
* 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.
*/
public abstract void writeString(String text)
throws 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.
*/
public abstract void writeString(char[] text, int offset, int len)
throws IOException, JsonGenerationException;
/**
* Method similar to {@link #writeString(String)}, but that takes
* {@link SerializableString} which can make this potentially
* more efficient to call as generator may be able to reuse
* quoted and/or encoded representation.
*<p>
* Default implementation just calls {@link #writeString(String)};
* sub-classes should override it with more efficient implementation
* if possible.
*/
public abstract void writeString(SerializableString text)
throws IOException, JsonGenerationException;
/**
* Method similar to {@link #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.
*<p>
* Note that some backends may choose not to support this method: for
* example, if underlying destination is a {@link java.io.Writer}
* using this method would require UTF-8 decoding.
* If so, implementation may instead choose to throw a
* {@link UnsupportedOperationException} due to ineffectiveness
* of having to decode input.
*/
public abstract void writeRawUTF8String(byte[] text, int offset, int length)
throws IOException, JsonGenerationException;
/**
* Method similar to {@link #writeString(String)} but that takes as its input
* a UTF-8 encoded String which has <b>not</b> 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.
*<p>
* Note that some backends may choose not to support this method: for
* example, if underlying destination is a {@link java.io.Writer}
* using this method would require UTF-8 decoding.
* In this case
* generator implementation may instead choose to throw a
* {@link UnsupportedOperationException} due to ineffectiveness
* of having to decode input.
*/
public abstract void writeUTF8String(byte[] text, int offset, int length)
throws IOException, JsonGenerationException;
/*
/**********************************************************
/* Public API, write methods, binary/raw content
/**********************************************************
*/
/**
* Method that will force generator to copy
* input text verbatim with <b>no</b> 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
* {@link #writeRawValue(String)} instead.
*<p>
* Note that not all generator implementations necessarily support
* such by-pass methods: those that do not will throw
* {@link UnsupportedOperationException}.
*/
public abstract void writeRaw(String text)
throws IOException, JsonGenerationException;
/**
* Method that will force generator to copy
* input text verbatim with <b>no</b> 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
* {@link #writeRawValue(String)} instead.
*<p>
* Note that not all generator implementations necessarily support
* such by-pass methods: those that do not will throw
* {@link UnsupportedOperationException}.
*/
public abstract void writeRaw(String text, int offset, int len)
throws IOException, JsonGenerationException;
/**
* Method that will force generator to copy
* input text verbatim with <b>no</b> 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
* {@link #writeRawValue(String)} instead.
*<p>
* Note that not all generator implementations necessarily support
* such by-pass methods: those that do not will throw
* {@link UnsupportedOperationException}.
*/
public abstract void writeRaw(char[] text, int offset, int len)
throws IOException, JsonGenerationException;
/**
* Method that will force generator to copy
* input text verbatim with <b>no</b> 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
* {@link #writeRawValue(String)} instead.
*<p>
* Note that not all generator implementations necessarily support
* such by-pass methods: those that do not will throw
* {@link UnsupportedOperationException}.
*/
public abstract void writeRaw(char c)
throws IOException, JsonGenerationException;
/**
* Method that will force generator to copy
* input text verbatim with <b>no</b> 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
* {@link #writeRawValue(String)} instead.
*<p>
* Note that not all generator implementations necessarily support
* such by-pass methods: those that do not will throw
* {@link UnsupportedOperationException}.
*<p>
* The default implementation delegates to {@link #writeRaw(String)};
* other backends that support raw inclusion of text are encouraged
* to implement it in more efficient manner (especially if they
* use UTF-8 encoding).
*
* @since 2.1
*/
public void writeRaw(SerializableString raw)
throws IOException, JsonGenerationException {
writeRaw(raw.getValue());
}
/**
* 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.
*/
public abstract void writeRawValue(String text)
throws IOException, JsonGenerationException;
public abstract void writeRawValue(String text, int offset, int len)
throws IOException, JsonGenerationException;
public abstract void writeRawValue(char[] text, int offset, int len)
throws 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
*<p>
* 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 {@link JsonParser} implementations
* are required to accept such "long line base64"; as do
* typical production-level base64 decoders.
*
* @param 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.
*/
public abstract void writeBinary(Base64Variant b64variant,
byte[] data, int offset, int len)
throws IOException, JsonGenerationException;
/**
* Similar to {@link #writeBinary(Base64Variant,byte[],int,int)},
* but default to using the Jackson default Base64 variant
* (which is {@link Base64Variants#MIME_NO_LINEFEEDS}).
*/
public void writeBinary(byte[] data, int offset, int len)
throws IOException, JsonGenerationException
{
writeBinary(Base64Variants.getDefaultVariant(), data, offset, len);
}
/**
* Similar to {@link #writeBinary(Base64Variant,byte[],int,int)},
* but assumes default to using the Jackson default Base64 variant
* (which is {@link Base64Variants#MIME_NO_LINEFEEDS}). Also
* assumes that whole byte array is to be output.
*/
public void writeBinary(byte[] data)
throws IOException, JsonGenerationException
{
writeBinary(Base64Variants.getDefaultVariant(), data, 0, data.length);
}
/**
* Similar to {@link #writeBinary(Base64Variant,InputStream,int)},
* but assumes default to using the Jackson default Base64 variant
* (which is {@link Base64Variants#MIME_NO_LINEFEEDS}).
*
* @param data InputStream to use for reading binary data to write.
* Will not be closed after successful write operation
* @param dataLength (optional) number of bytes that will be available;
* or -1 to be indicate it is not known. Note that implementations
* need not support cases where length is not known in advance; this
* depends on underlying data format: JSON output does NOT require length,
* other formats may
*/
public int writeBinary(InputStream data, int dataLength)
throws IOException, JsonGenerationException {
return writeBinary(Base64Variants.getDefaultVariant(), data, dataLength);
}
/**
* Method similar to {@link #writeBinary(Base64Variant,byte[],int,int)},
* but where input is provided through a stream, allowing for incremental
* writes without holding the whole input in memory.
*
* @param b64variant Base64 variant to use
* @param data InputStream to use for reading binary data to write.
* Will not be closed after successful write operation
* @param dataLength (optional) number of bytes that will be available;
* or -1 to be indicate it is not known.
* If a positive length is given, <code>data</code> MUST provide at least
* that many bytes: if not, an exception will be thrown.
* Note that implementations
* need not support cases where length is not known in advance; this
* depends on underlying data format: JSON output does NOT require length,
* other formats may.
*
* @return Number of bytes read from <code>data</code> and written as binary payload
*
* @since 2.1
*/
public abstract int writeBinary(Base64Variant b64variant,
InputStream data, int dataLength)
throws IOException, JsonGenerationException;
/*
/**********************************************************
/* Public API, write methods, other value types
/**********************************************************
*/
/**
* 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.
*/
public abstract void writeNumber(int v)
throws 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.
*/
public abstract void writeNumber(long v)
throws 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.
*/
public abstract void writeNumber(BigInteger v)
throws 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.
*/
public abstract void writeNumber(double d)
throws 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.
*/
public abstract void writeNumber(float f)
throws 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.
*/
public abstract void writeNumber(BigDecimal dec)
throws IOException, JsonGenerationException;
/**
* 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
* {@link #writeString} method can not be used; nor
* {@link #writeRaw} because that does not properly handle
* value separators needed in Array or Object contexts.
*<p>
* 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 {@link UnsupportedOperationException}.
*/
public abstract void writeNumber(String encodedValue)
throws IOException, JsonGenerationException,
UnsupportedOperationException;
/**
* 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.
*/
public abstract void writeBoolean(boolean state)
throws 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.
*/
public abstract void writeNull()
throws IOException, JsonGenerationException;
/*
/**********************************************************
/* Public API, write methods, serializing Java objects
/**********************************************************
*/
/**
* 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.
* <b>NOTE</b>: generator must have its <b>object codec</b>
* set to non-null value; for generators created by a mapping
* factory this is the case, for others not.
*/
public abstract void writeObject(Object pojo)
throws 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
* {@link #writeObject} with given node, but is added
* for convenience and to make code more explicit in cases
* where it deals specifically with trees.
*/
public abstract void writeTree(TreeNode rootNode)
throws IOException, JsonProcessingException;
/*
/**********************************************************
/* Public API, convenience field write methods
/**********************************************************
*/
/**
* Convenience method for outputting a field entry ("member")
* that has a String value. Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeString(value);
*</pre>
*<p>
* Note: many performance-sensitive implementations override this method
*/
public void writeStringField(String fieldName, String value)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeString(value);
}
/**
* Convenience method for outputting a field entry ("member")
* that has a boolean value. Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeBoolean(value);
*</pre>
*/
public final void writeBooleanField(String fieldName, boolean value)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeBoolean(value);
}
/**
* Convenience method for outputting a field entry ("member")
* that has JSON literal value null. Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeNull();
*</pre>
*/
public final void writeNullField(String fieldName)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeNull();
}
/**
* Convenience method for outputting a field entry ("member")
* that has the specified numeric value. Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeNumber(value);
*</pre>
*/
public final void writeNumberField(String fieldName, int value)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeNumber(value);
}
/**
* Convenience method for outputting a field entry ("member")
* that has the specified numeric value. Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeNumber(value);
*</pre>
*/
public final void writeNumberField(String fieldName, long value)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeNumber(value);
}
/**
* Convenience method for outputting a field entry ("member")
* that has the specified numeric value. Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeNumber(value);
*</pre>
*/
public final void writeNumberField(String fieldName, double value)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeNumber(value);
}
/**
* Convenience method for outputting a field entry ("member")
* that has the specified numeric value. Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeNumber(value);
*</pre>
*/
public final void writeNumberField(String fieldName, float value)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeNumber(value);
}
/**
* Convenience method for outputting a field entry ("member")
* that has the specified numeric value.
* Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeNumber(value);
*</pre>
*/
public final void writeNumberField(String fieldName, BigDecimal value)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeNumber(value);
}
/**
* Convenience method for outputting a field entry ("member")
* that contains specified data in base64-encoded form.
* Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeBinary(value);
*</pre>
*/
public final void writeBinaryField(String fieldName, byte[] data)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeBinary(data);
}
/**
* Convenience method for outputting a field entry ("member")
* (that will contain a JSON Array value), and the START_ARRAY marker.
* Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeStartArray();
*</pre>
*<p>
* Note: caller still has to take care to close the array
* (by calling {#link #writeEndArray}) after writing all values
* of the value Array.
*/
public final void writeArrayFieldStart(String fieldName)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeStartArray();
}
/**
* Convenience method for outputting a field entry ("member")
* (that will contain a JSON Object value), and the START_OBJECT marker.
* Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeStartObject();
*</pre>
*<p>
* Note: caller still has to take care to close the Object
* (by calling {#link #writeEndObject}) after writing all
* entries of the value Object.
*/
public final void writeObjectFieldStart(String fieldName)
throws IOException, JsonGenerationException
{
writeFieldName(fieldName);
writeStartObject();
}
/**
* Convenience method for outputting a field entry ("member")
* that has contents of specific Java object as its value.
* Equivalent to:
*<pre>
* writeFieldName(fieldName);
* writeObject(pojo);
*</pre>
*/
public final void writeObjectField(String fieldName, Object pojo)
throws IOException, JsonProcessingException
{
writeFieldName(fieldName);
writeObject(pojo);
}
/*
/**********************************************************
/* Public API, copy-through methods
/**********************************************************
*/
/**
* Method for copying contents of the current event that
* the given parser instance points to.
* Note that the method <b>will not</b> copy any other events,
* such as events contained within Json Array or Object structures.
*<p>
* 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)
*/
public abstract void copyCurrentEvent(JsonParser jp)
throws IOException, JsonProcessingException;
/**
* Method for copying contents of the current event
* <b>and following events that it encloses</b>
* the given parser instance points to.
*<p>
* So what constitutes enclosing? Here is the list of
* events that have associated enclosed events that will
* get copied:
*<ul>
* <li>{@link JsonToken#START_OBJECT}:
* all events up to and including matching (closing)
* {@link JsonToken#END_OBJECT} will be copied
* </li>
* <li>{@link JsonToken#START_ARRAY}
* all events up to and including matching (closing)
* {@link JsonToken#END_ARRAY} will be copied
* </li>
* <li>{@link JsonToken#FIELD_NAME} the logical value (which
* can consist of a single scalar value; or a sequence of related
* events for structured types (Json Arrays, Objects)) will
* be copied along with the name itself. So essentially the
* whole <b>field entry</b> (name and value) will be copied.
* </li>
*</ul>
*<p>
* After calling this method, parser will point to the
* <b>last event</b> 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.
*/
public abstract void copyCurrentStructure(JsonParser jp)
throws IOException, JsonProcessingException;
/*
/**********************************************************
/* Public API, context access
/**********************************************************
*/
/**
* @return Context object that can give information about logical
* position within generated json content.
*/
public abstract JsonStreamContext getOutputContext();
/*
/**********************************************************
/* Public API, buffer handling
/**********************************************************
*/
/**
* Method called to flush any buffered content to the underlying
* target (output stream, writer), and to flush the target itself
* as well.
*/
public abstract void flush() throws IOException;
/**
* Method that can be called to determine whether this generator
* is closed or not. If it is closed, no more output can be done.
*/
public abstract boolean isClosed();
/*
/**********************************************************
/* Closeable implementation
/**********************************************************
*/
/**
* Method called to close this generator, so that no more content
* can be written.
*<p>
* 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 {@link 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.
*/
// @Override
public abstract void close() throws IOException;
}