Module com.erudika.para.core

Package com.erudika.para.core.utils

Class ParaObjectUtils

java.lang.Object

com.erudika.para.core.utils.ParaObjectUtils

public final class ParaObjectUtils
extends Object

Contains methods for object/grid mapping, JSON serialization, class scanning and resolution.

Author:

Alex Bogdanovski [[email protected]]

Method Summary

Modifier and Type	Method	Description
static <P extends ParaObject> P	fromJSON(String json)	Converts a JSON string to a domain object.
static Map<String,String>	getAllTypes(App app)	Returns a map of all registered types.
static <P extends ParaObject> Map<String,Object>	getAnnotatedFields(P pojo)
static <P extends ParaObject> Map<String,Object>	getAnnotatedFields(P pojo, boolean flattenNestedObjectsToString)
static <P extends ParaObject> Map<String,Object>	getAnnotatedFields(P pojo, Class<? extends Annotation> filter)
static <P extends ParaObject> Map<String,Object>	getAnnotatedFields(P pojo, Class<? extends Annotation> filter, boolean flattenNestedObjectsToString)	Returns a map of annotated fields of a domain object.
static String	getAppidFromAuthHeader(String authorization)	Returns the app identifier by parsing the Authorization.
static Map<String,Class<? extends ParaObject>>	getCoreClassesMap()	Searches through the Para core package and Config.CORE_PACKAGE_NAME package for ParaObject subclasses and adds their names them to the map.
static Map<String,String>	getCoreParaTypes()	Returns a map of the core data types declared in Para Core only.
static Map<String,String>	getCoreTypes()	Returns a map of the core data types.
static com.fasterxml.jackson.databind.ObjectMapper	getJsonMapper()	A Jackson ObjectMapper.
static com.fasterxml.jackson.databind.ObjectReader	getJsonReader(Class<?> type)	A Jackson JSON reader.
static com.fasterxml.jackson.databind.ObjectWriter	getJsonWriter()	A Jackson JSON writer.
static com.fasterxml.jackson.databind.ObjectWriter	getJsonWriterNoIdent()	A Jackson JSON writer.
static void	registerCoreClasses(Class<? extends ParaObject>... classes)	Explicitly registers core classes for reflection.
static <P extends ParaObject> P	setAnnotatedFields(Map<String,Object> data)
static <P extends ParaObject> P	setAnnotatedFields(P pojo, Map<String,Object> data, Class<? extends Annotation> filter)	Converts a map of fields/values to a domain object.
static Class<? extends ParaObject>	toClass(String type)	Converts a class name to a real Class object.
static Class<? extends ParaObject>	toClass(String type, Class<? extends ParaObject> defaultClass)	Converts a class name to a real ParaObject subclass.
static <P extends ParaObject> String	toJSON(P obj)	Converts a domain object to JSON.
static <P extends ParaObject> P	toObject(App app, String type)	Constructs a new instance of a core object.
static boolean	typesMatch(ParaObject so)	Checks if the type of an object matches its real Class name.

Methods inherited from class java.lang.Object

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

Method Details

getJsonMapper

public static com.fasterxml.jackson.databind.ObjectMapper getJsonMapper()

A Jackson ObjectMapper.

Returns:

JSON object mapper

getJsonReader

public static com.fasterxml.jackson.databind.ObjectReader getJsonReader(Class<?> type)

A Jackson JSON reader.

Parameters:

type - the type to read

Returns:

JSON object reader

getJsonWriter

public static com.fasterxml.jackson.databind.ObjectWriter getJsonWriter()

A Jackson JSON writer. Pretty print is on.

Returns:

JSON object writer

getJsonWriterNoIdent

public static com.fasterxml.jackson.databind.ObjectWriter getJsonWriterNoIdent()

A Jackson JSON writer. Pretty print is off.

Returns:

JSON object writer with indentation disabled

getCoreTypes

public static Map<String,String> getCoreTypes()

Returns a map of the core data types.

Returns:

a map of type plural - type singular form

getCoreParaTypes

public static Map<String,String> getCoreParaTypes()

Returns a map of the core data types declared in Para Core only.

Returns:

a map of type plural - type singular form

getAllTypes

public static Map<String,String> getAllTypes(App app)

Returns a map of all registered types.

Parameters:

app - the app to search for custom types

Returns:

a map of plural - singular form of type names

getAppidFromAuthHeader

public static String getAppidFromAuthHeader(String authorization)

Returns the app identifier by parsing the Authorization.

Parameters:

authorization - Authorization header

Returns:

appid

typesMatch

public static boolean typesMatch(ParaObject so)

Checks if the type of an object matches its real Class name.

Parameters:

so - an object

Returns:

true if the types match

getAnnotatedFields

public static <P extends ParaObject>
Map<String,Object> getAnnotatedFields(P pojo)

Type Parameters:

P - the object type

Parameters:

pojo - the object to convert to a map

Returns:

a map of fields and their values

See Also:

• getAnnotatedFields(com.erudika.para.core.ParaObject, java.lang.Class, boolean)

getAnnotatedFields

public static <P extends ParaObject>
Map<String,Object> getAnnotatedFields(P pojo,
 Class<? extends Annotation> filter)

Type Parameters:

P - the object type

Parameters:

pojo - the object to convert to a map

filter - a filter annotation. fields that have it will be skipped

Returns:

a map of fields and their values

See Also:

• getAnnotatedFields(com.erudika.para.core.ParaObject, java.lang.Class, boolean)

getAnnotatedFields

public static <P extends ParaObject>
Map<String,Object> getAnnotatedFields(P pojo,
 boolean flattenNestedObjectsToString)

Type Parameters:

P - the object type

Parameters:

pojo - the object to convert to a map

flattenNestedObjectsToString - flattens nested objects to a JSON string, true by default.

Returns:

a map of fields and their values

See Also:

• getAnnotatedFields(com.erudika.para.core.ParaObject, java.lang.Class, boolean)

getAnnotatedFields

public static <P extends ParaObject>
Map<String,Object> getAnnotatedFields(P pojo,
 Class<? extends Annotation> filter,
 boolean flattenNestedObjectsToString)

Returns a map of annotated fields of a domain object. Only annotated fields are returned. This method forms the basis of an Object/Grid Mapper. It converts an object to a map of key/value pairs. That map can later be persisted to a data store.
If flattenNestedObjectsToString is true all field values that are objects (i.e. not primitive types or wrappers) are converted to a JSON string otherwise they are left as they are and will be serialized as regular JSON objects later (structure is preserved). Null is considered a primitive type. Transient fields and serialVersionUID are skipped.

Type Parameters:

P - the object type

Parameters:

pojo - the object to convert to a map

filter - a filter annotation. fields that have it will be skipped

flattenNestedObjectsToString - true if you want to flatten the nested objects to a JSON string.

Returns:

a map of fields and their values

setAnnotatedFields

public static <P extends ParaObject> P setAnnotatedFields(Map<String,Object> data)

Type Parameters:

P - the object type

Parameters:

data - the map of fields/values

Returns:

the populated object

See Also:

• setAnnotatedFields(com.erudika.para.core.ParaObject, java.util.Map, java.lang.Class)

setAnnotatedFields

public static <P extends ParaObject> P setAnnotatedFields(P pojo,
 Map<String,Object> data,
 Class<? extends Annotation> filter)

Converts a map of fields/values to a domain object. Only annotated fields are populated. This method forms the basis of an Object/Grid Mapper.
Map values that are JSON objects are converted to their corresponding Java types. Nulls and primitive types are preserved.

Type Parameters:

P - the object type

Parameters:

pojo - the object to populate with data

data - the map of fields/values

filter - a filter annotation. fields that have it will be skipped

Returns:

the populated object

toObject

public static <P extends ParaObject> P toObject(App app,
 String type)

Constructs a new instance of a core object.

Type Parameters:

P - the object type

Parameters:

app - an app object

type - the simple name of a class

Returns:

a new instance of a core class. Defaults to Sysprop.

See Also:

• toClass(java.lang.String)

toClass

public static Class<? extends ParaObject> toClass(String type)

Converts a class name to a real Class object.

Parameters:

type - the simple name of a class

Returns:

the Class object or Sysprop if the class was not found.

See Also:

• Class.forName(java.lang.String)

toClass

public static Class<? extends ParaObject> toClass(String type,
 Class<? extends ParaObject> defaultClass)

Converts a class name to a real ParaObject subclass. Defaults to Sysprop if the class was not found in the core package path.

Parameters:

type - the simple name of a class

defaultClass - returns this type if the requested class was not found on the classpath.

Returns:

the Class object. Returns null if defaultClass is null.

See Also:

• Class.forName(java.lang.String)
• Sysprop

getCoreClassesMap

public static Map<String,Class<? extends ParaObject>> getCoreClassesMap()

Searches through the Para core package and Config.CORE_PACKAGE_NAME package for ParaObject subclasses and adds their names them to the map.

Returns:

a map of simple class names (lowercase) to class objects

registerCoreClasses

public static void registerCoreClasses(Class<? extends ParaObject>... classes)

Explicitly registers core classes for reflection.

Parameters:

classes - a list of classes

fromJSON

public static <P extends ParaObject> P fromJSON(String json)

Converts a JSON string to a domain object. If we can't match the JSON to a core object, we fall back to Sysprop.

Type Parameters:

P - type of object to convert

Parameters:

json - the JSON string

Returns:

a core domain object or null if the string was blank

toJSON

public static <P extends ParaObject> String toJSON(P obj)

Converts a domain object to JSON.

Type Parameters:

P - type of object to convert

Parameters:

obj - a domain object

Returns:

the JSON representation of that object