org.apache.juneau.json

Class JsonSerializer

java.lang.Object

org.apache.juneau.Context

org.apache.juneau.BeanContext

org.apache.juneau.serializer.Serializer

org.apache.juneau.serializer.WriterSerializer

org.apache.juneau.json.JsonSerializer

Direct Known Subclasses:

JsonSchemaSerializer, JsonSerializer.Readable, JsonSerializer.Simple, JsonSerializer.SimpleReadable, JsonSerializer.SimpleReadableSafe

public class JsonSerializer
extends WriterSerializer

Serializes POJO models to JSON.

Media types

Handles Accept types: application/json, text/json

Produces Content-Type types: application/json

Description

The conversion is as follows...

• Maps (e.g. HashMaps, TreeMaps) are converted to JSON objects.
• Collections (e.g. HashSets, LinkedLists) and Java arrays are converted to JSON arrays.
• Strings are converted to JSON strings.
• Numbers (e.g. Integer, Long, Double) are converted to JSON numbers.
• Booleans are converted to JSON booleans.
• nulls are converted to JSON nulls.
• arrays are converted to JSON arrays.
• beans are converted to JSON objects.

The types above are considered "JSON-primitive" object types. Any non-JSON-primitive object types are transformed into JSON-primitive object types through PojoSwaps associated through the BeanContextBuilder.pojoSwaps(Class...) method. Several default transforms are provided for transforming Dates, Enums, Iterators, etc...

This serializer provides several serialization options. Typically, one of the predefined DEFAULT serializers will be sufficient. However, custom serializers can be constructed to fine-tune behavior.

Behavior-specific subclasses

The following direct subclasses are provided for convenience:

• JsonSerializer.Simple - Default serializer, single quotes, simple mode.
• JsonSerializer.SimpleReadable - Default serializer, single quotes, simple mode, with whitespace.

Example:

// Use one of the default serializers to serialize a POJO String json = JsonSerializer.DEFAULT.serialize(someObject); // Create a custom serializer for lax syntax using single quote characters JsonSerializer serializer = JsonSerializer.create().simple().sq().build(); // Clone an existing serializer and modify it to use single-quotes JsonSerializer serializer = JsonSerializer.DEFAULT.builder().sq().build(); // Serialize a POJO to JSON String json = serializer.serialize(someObject);

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	JsonSerializer.Readable Default serializer, with whitespace.
static class	JsonSerializer.Simple Default serializer, single quotes, simple mode.
static class	JsonSerializer.SimpleReadable Default serializer, single quotes, simple mode, with whitespace.
static class	JsonSerializer.SimpleReadableSafe Default serializer, single quotes, simple mode, with whitespace and recursion detection.

Field Summary

Fields

Modifier and Type	Field and Description
static JsonSerializer	DEFAULT Default serializer, all default settings.
static JsonSerializer	DEFAULT_LAX Default serializer, single quotes, simple mode.
static JsonSerializer	DEFAULT_LAX_READABLE Default serializer, single quotes, simple mode, with whitespace.
static JsonSerializer	DEFAULT_LAX_READABLE_SAFE Default serializer, single quotes, simple mode, with whitespace and recursion detection.
static JsonSerializer	DEFAULT_READABLE Default serializer, all default settings.
static String	JSON_addBeanTypeProperties Configuration property: Add "_type" properties when needed.
static String	JSON_escapeSolidus Configuration property: Prefix solidus '/' characters with escapes.
static String	JSON_simpleMode Configuration property: Simple JSON mode.

Fields inherited from class org.apache.juneau.serializer.Serializer

SERIALIZER_abridged, SERIALIZER_addBeanTypeProperties, SERIALIZER_detectRecursions, SERIALIZER_ignoreRecursions, SERIALIZER_initialDepth, SERIALIZER_listener, SERIALIZER_maxDepth, SERIALIZER_maxIndent, SERIALIZER_quoteChar, SERIALIZER_sortCollections, SERIALIZER_sortMaps, SERIALIZER_trimEmptyCollections, SERIALIZER_trimEmptyMaps, SERIALIZER_trimNullProperties, SERIALIZER_trimStrings, SERIALIZER_uriContext, SERIALIZER_uriRelativity, SERIALIZER_uriResolution, SERIALIZER_useWhitespace

Fields inherited from class org.apache.juneau.BeanContext

BEAN_beanClassVisibility, BEAN_beanConstructorVisibility, BEAN_beanDictionary, BEAN_beanDictionary_add, BEAN_beanDictionary_remove, BEAN_beanFieldVisibility, BEAN_beanFilters, BEAN_beanFilters_add, BEAN_beanFilters_remove, BEAN_beanMapPutReturnsOldValue, BEAN_beanMethodVisibility, BEAN_beansRequireDefaultConstructor, BEAN_beansRequireSerializable, BEAN_beansRequireSettersForGetters, BEAN_beansRequireSomeProperties, BEAN_beanTypePropertyName, BEAN_debug, BEAN_excludeProperties, BEAN_ignoreInvocationExceptionsOnGetters, BEAN_ignoreInvocationExceptionsOnSetters, BEAN_ignorePropertiesWithoutSetters, BEAN_ignoreUnknownBeanProperties, BEAN_ignoreUnknownNullBeanProperties, BEAN_implClasses, BEAN_includeProperties, BEAN_locale, BEAN_mediaType, BEAN_notBeanClasses, BEAN_notBeanClasses_add, BEAN_notBeanClasses_remove, BEAN_notBeanPackages, BEAN_notBeanPackages_add, BEAN_notBeanPackages_remove, BEAN_pojoSwaps, BEAN_pojoSwaps_add, BEAN_pojoSwaps_remove, BEAN_propertyNamer, BEAN_sortProperties, BEAN_timeZone, BEAN_useInterfaceProxies, BEAN_useJavaBeanIntrospector, DEFAULT_SORTED

Constructor Summary

Constructors

Constructor and Description
JsonSerializer(PropertyStore ps) Constructor.
JsonSerializer(PropertyStore ps, String produces, String... accept) Constructor.

Method Summary

Modifier and Type	Method and Description
ObjectMap	asMap() Returns the properties defined on this bean context as a simple map for debugging purposes.
JsonSerializerBuilder	builder() Creates a builder from this context object.
static JsonSerializerBuilder	create() Instantiates a new clean-slate JsonSerializerBuilder object.
WriterSerializerSession	createSession(SerializerSessionArgs args) Create the session object used for actual serialization of objects.
JsonSchemaSerializer	getSchemaSerializer() Returns the schema serializer based on the settings of this serializer.

Methods inherited from class org.apache.juneau.serializer.WriterSerializer

isWriterSerializer, println, serialize, toString, toStringObject

Methods inherited from class org.apache.juneau.serializer.Serializer

createDefaultSessionArgs, createSession, getMediaTypes, getResponseContentType, serialize

Methods inherited from class org.apache.juneau.BeanContext

_class, createBeanSession, createBeanSession, createDefaultBeanSessionArgs, createSession, createSession, dumpCacheStats, getBeanMeta, getBeanRegistry, getBeanTypePropertyName, getClassMeta, getClassMeta, getClassMetaForObject, getExcludeProperties, getImplClassConstructor, getIncludeProperties, hasSameCache, isBean, isNotABean, newInstance, newInstance, newInstanceFromOuter, object, resolveClassMeta, string

Methods inherited from class org.apache.juneau.Context

equals, getArrayProperty, getArrayProperty, getBooleanProperty, getClassArrayProperty, getClassArrayProperty, getClassArrayProperty, getClassListProperty, getClassListProperty, getClassMapProperty, getClassMapProperty, getClassProperty, getClassSetProperty, getClassSetProperty, getInstanceArrayProperty, getInstanceArrayProperty, getInstanceArrayProperty, getInstanceProperty, getInstanceProperty, getInstanceProperty, getIntegerProperty, getListProperty, getListProperty, getLongProperty, getMapProperty, getProperty, getProperty, getPropertyKeys, getPropertyStore, getSetProperty, getSetProperty, getStringProperty, hashCode, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

JSON_addBeanTypeProperties

public static final String JSON_addBeanTypeProperties

Configuration property: Add "_type" properties when needed.

Property:

• Name: "JsonSerializer.addBeanTypeProperties.b"
• Data type: Boolean
• Default: false
• Session-overridable: true
• Methods:
  • JsonSerializerBuilder.addBeanTypeProperties(boolean)

Description:

If true, then "_type" properties will be added to beans if their type cannot be inferred through reflection.

When present, this value overrides the Serializer.SERIALIZER_addBeanTypeProperties setting and is provided to customize the behavior of specific serializers in a SerializerGroup.

See Also:

Constant Field Values

JSON_escapeSolidus

public static final String JSON_escapeSolidus

Configuration property: Prefix solidus '/' characters with escapes.

Property:

• Name: "JsonSerializer.escapeSolidus.b"
• Data type: Boolean
• Default: false
• Session-overridable: true
• Methods:
  • JsonSerializerBuilder.escapeSolidus(boolean)
  • JsonSerializerBuilder.escapeSolidus()

Description:

If true, solidus (e.g. slash) characters should be escaped. The JSON specification allows for either format.
However, if you're embedding JSON in an HTML script tag, this setting prevents confusion when trying to serialize <\/script>.

Example:

// Create a JSON serializer that escapes solidus characters. WriterSerializer s = JsonSerializer .create() .simple() .escapeSolidus() .build(); // Same, but use property. WriterSerializer s = JsonSerializer .create() .simple() .set(JSON_escapeSolidus, true) .build(); // Produces: "{foo:'<\/bar>'" String json = s.serialize(new ObjectMap().append("foo", "</bar>");

See Also:

Constant Field Values

JSON_simpleMode

public static final String JSON_simpleMode

Configuration property: Simple JSON mode.

Property:

• Name: "JsonSerializer.simpleMode.b"
• Data type: Boolean
• Default: false
• Session-overridable: true
• Methods:
  • JsonSerializerBuilder.simple(boolean)
  • JsonSerializerBuilder.simple()
  • JsonSerializerBuilder.ssq()

Description:

If true, JSON attribute names will only be quoted when necessary.
Otherwise, they are always quoted.

Attributes do not need to be quoted when they conform to the following:

1. They start with an ASCII character or '_'.
2. They contain only ASCII characters or numbers or '_'.
3. They are not one of the following reserved words:

   arguments, break, case, catch, class, const, continue, debugger, default, delete, do, else, enum, eval, export, extends, false, finally, for, function, if, implements, import, in, instanceof, interface, let, new, null, package, private, protected, public, return, static, super, switch, this, throw, true, try, typeof, var, void, while, with, undefined, yield

Example:

// Create a JSON serializer in normal mode. WriterSerializer s1 = JsonSerializer .create() .build(); // Create a JSON serializer in simple mode. WriterSerializer s2 = JsonSerializer .create() .simple() .build(); ObjectMap m = new ObjectMap() .append("foo", "x1") .append("_bar", "x2") .append(" baz ", "x3") .append("123", "x4") .append("return", "x5"); .append("", "x6"); // Produces: // { // "foo": "x1" // "_bar": "x2" // " baz ": "x3" // "123": "x4" // "return": "x5" // "": "x6" // } String json1 = s1.serialize(m); // Produces: // { // foo: "x1" // _bar: "x2" // " baz ": "x3" // "123": "x4" // "return": "x5" // "": "x6" // } String json2 = s2.serialize(m);

See Also:

Constant Field Values

DEFAULT

public static final JsonSerializer DEFAULT

Default serializer, all default settings.

DEFAULT_READABLE

public static final JsonSerializer DEFAULT_READABLE

Default serializer, all default settings.

DEFAULT_LAX

public static final JsonSerializer DEFAULT_LAX

Default serializer, single quotes, simple mode.

DEFAULT_LAX_READABLE

public static final JsonSerializer DEFAULT_LAX_READABLE

Default serializer, single quotes, simple mode, with whitespace.

DEFAULT_LAX_READABLE_SAFE

public static final JsonSerializer DEFAULT_LAX_READABLE_SAFE

Default serializer, single quotes, simple mode, with whitespace and recursion detection. Note that recursion detection introduces a small performance penalty.

Constructor Detail

JsonSerializer

public JsonSerializer(PropertyStore ps)

Constructor.

Parameters:

ps - The property store containing all the settings for this object.

JsonSerializer

public JsonSerializer(PropertyStore ps,
                      String produces,
                      String... accept)

Constructor.

Parameters:

ps - The property store containing all the settings for this object.

produces - The media type that this serializer produces.

accept - The accept media types that the serializer can handle.

Can contain meta-characters per the media-type specification of RFC2616/14.1

If empty, then assumes the only media type supported is produces.

For example, if this serializer produces "application/json" but should handle media types of "application/json" and "text/json", then the arguments should be:

super(ps, "application/json", "application/json", "text/json");

...or...

super(ps, "application/json", "*/json");

Method Detail

builder

public JsonSerializerBuilder builder()

Description copied from class: Context

Creates a builder from this context object.

Builders are used to define new contexts (e.g. serializers, parsers) based on existing configurations.

Overrides:

builder in class Serializer

Returns:

A new ContextBuilder object.

create

public static JsonSerializerBuilder create()

Instantiates a new clean-slate JsonSerializerBuilder object.

This is equivalent to simply calling new JsonSerializerBuilder().

Returns:

A new JsonSerializerBuilder object.

getSchemaSerializer

public JsonSchemaSerializer getSchemaSerializer()

Returns the schema serializer based on the settings of this serializer.

Note that this method creates a builder initialized to all default settings, whereas builder() copies the settings of the object called on.

Returns:

The schema serializer.

createSession

public WriterSerializerSession createSession(SerializerSessionArgs args)

Description copied from class: Serializer

Create the session object used for actual serialization of objects.

Specified by:

createSession in class WriterSerializer

Parameters:

args - Runtime arguments. These specify session-level information such as locale and URI context. It also include session-level properties that override the properties defined on the bean and serializer contexts.

Returns:

The new session object.

asMap

public ObjectMap asMap()

Description copied from class: Context

Returns the properties defined on this bean context as a simple map for debugging purposes.

Overrides:

asMap in class Serializer

Returns:

A new map containing the properties defined on this context.