Class Schema

java.lang.Object

java.util.AbstractMap<String,Object>

java.util.HashMap<String,Object>

org.refcodes.schema.Schema

All Implemented Interfaces:

Serializable, Cloneable, Map<String,Object>, org.refcodes.exception.ExceptionAccessor<Throwable>, org.refcodes.mixin.AliasAccessor, org.refcodes.mixin.ChildrenAccessor<Schema[]>, org.refcodes.mixin.Clearable, org.refcodes.mixin.DescriptionAccessor, org.refcodes.mixin.EmptyAccessor, org.refcodes.mixin.HashAccessor, org.refcodes.mixin.IdentifierAccessor, org.refcodes.mixin.KeyAccessor<String>, org.refcodes.mixin.StereotypeAccessor<String>, org.refcodes.mixin.TypeAccessor, org.refcodes.mixin.ValueAccessor<Object>, org.refcodes.ontology.Ontology, org.refcodes.struct.Containable, org.refcodes.struct.ImmutableTable<String,Object>, org.refcodes.struct.ImmutableTable.MutableTable<String,Object>, org.refcodes.struct.Keys<String,Object>, org.refcodes.struct.Keys.MutableKeys<String,Object>, org.refcodes.struct.Keys.MutableValues<String,Object>

public class Schema
extends HashMap<String,Object>
implements org.refcodes.ontology.Ontology, org.refcodes.mixin.ChildrenAccessor<Schema[]>, org.refcodes.mixin.IdentifierAccessor, org.refcodes.mixin.AliasAccessor, org.refcodes.mixin.TypeAccessor, org.refcodes.mixin.HashAccessor, org.refcodes.mixin.DescriptionAccessor, org.refcodes.mixin.KeyAccessor<String>, org.refcodes.mixin.StereotypeAccessor<String>, org.refcodes.exception.ExceptionAccessor<Throwable>, org.refcodes.mixin.ValueAccessor<Object>

A Schema is a lightweight, recursive description of an object graph.

A Schema is not the data structure itself. Instead, it captures diagnostic and documentation relevant metadata about an instance and its nested children. This enables rendering the structure as a notation such as JSON, XML or PlantUML by applying a SchemaVisitor.

A Schema consists of:

• A property map (this class extends Map) holding descriptive attributes such as identifier, alias, type, hash, value, description, stereotype, or exceptions.
• An optional ordered set of child Schema instances representing a nested structure.

Rendering is done via visit(SchemaVisitor) or via convenience methods such as toNotation(SchemaNotation). The default toString() returns a JSON like representation using SchemaNotation.JSON.

This type is intended for diagnostics, debugging, verification, and optional documentation generation. Implementations typically populate it through builder().

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Schema.Builder	Builder for creating Schema instances.

Nested classes/interfaces inherited from class AbstractMap

AbstractMap.SimpleEntry<K,V>, AbstractMap.SimpleImmutableEntry<K,V>

Nested classes/interfaces inherited from interface org.refcodes.mixin.AliasAccessor

org.refcodes.mixin.AliasAccessor.AliasBuilder<B>, org.refcodes.mixin.AliasAccessor.AliasMutator, org.refcodes.mixin.AliasAccessor.AliasProperty

Nested classes/interfaces inherited from interface org.refcodes.mixin.ChildrenAccessor

org.refcodes.mixin.ChildrenAccessor.ChildrenBuilder<T,B>, org.refcodes.mixin.ChildrenAccessor.ChildrenMutator<T>, org.refcodes.mixin.ChildrenAccessor.ChildrenProperty<T>

Nested classes/interfaces inherited from interface org.refcodes.mixin.DescriptionAccessor

org.refcodes.mixin.DescriptionAccessor.DescriptionBuilder<B>, org.refcodes.mixin.DescriptionAccessor.DescriptionMutator, org.refcodes.mixin.DescriptionAccessor.DescriptionProperty

Nested classes/interfaces inherited from interface org.refcodes.mixin.EmptyAccessor

org.refcodes.mixin.EmptyAccessor.EmptyBuilder<B>, org.refcodes.mixin.EmptyAccessor.EmptyMutator, org.refcodes.mixin.EmptyAccessor.EmptyProperty

Nested classes/interfaces inherited from interface org.refcodes.exception.ExceptionAccessor

org.refcodes.exception.ExceptionAccessor.ExceptionBuilder<EXC,B>, org.refcodes.exception.ExceptionAccessor.ExceptionMutator<EXC>, org.refcodes.exception.ExceptionAccessor.ExceptionProperty<EXC>

Nested classes/interfaces inherited from interface org.refcodes.mixin.HashAccessor

org.refcodes.mixin.HashAccessor.HashBuilder<B>, org.refcodes.mixin.HashAccessor.HashMutator, org.refcodes.mixin.HashAccessor.HashProperty

Nested classes/interfaces inherited from interface org.refcodes.mixin.IdentifierAccessor

org.refcodes.mixin.IdentifierAccessor.IdentifierBuilder<B>, org.refcodes.mixin.IdentifierAccessor.IdentifierMutator, org.refcodes.mixin.IdentifierAccessor.IdentifierProperty

Nested classes/interfaces inherited from interface org.refcodes.struct.ImmutableTable

org.refcodes.struct.ImmutableTable.MutableTable<K,V>

Nested classes/interfaces inherited from interface org.refcodes.mixin.KeyAccessor

org.refcodes.mixin.KeyAccessor.KeyBuilder<K,B>, org.refcodes.mixin.KeyAccessor.KeyMutator<K>, org.refcodes.mixin.KeyAccessor.KeyProperty<K>

Nested classes/interfaces inherited from interface org.refcodes.struct.Keys

org.refcodes.struct.Keys.MutableKeys<K,V>, org.refcodes.struct.Keys.MutableValues<K,V>

Nested classes/interfaces inherited from interface Map

Map.Entry<K,V>

Nested classes/interfaces inherited from interface org.refcodes.mixin.StereotypeAccessor

org.refcodes.mixin.StereotypeAccessor.StereotypeBuilder<T,B>, org.refcodes.mixin.StereotypeAccessor.StereotypeMutator<T>, org.refcodes.mixin.StereotypeAccessor.StereotypeProperty<T>

Nested classes/interfaces inherited from interface org.refcodes.mixin.TypeAccessor

org.refcodes.mixin.TypeAccessor.TypeBuilder<T,B>, org.refcodes.mixin.TypeAccessor.TypeMutator<T>, org.refcodes.mixin.TypeAccessor.TypeProperty<T>

Nested classes/interfaces inherited from interface org.refcodes.mixin.ValueAccessor

org.refcodes.mixin.ValueAccessor.ValueBuilder<V,B>, org.refcodes.mixin.ValueAccessor.ValueMutator<V>, org.refcodes.mixin.ValueAccessor.ValueProperty<V>

Field Summary

Fields

Modifier and Type	Field	Description
protected Schema[]	_children	Optional child schemas representing the nested structure (aggregation).
static final char	HASH_SEPARATOR	This separator is used to separate the hash code form on object's name.

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Schema()	Instantiates a new schema.
protected	Schema(Schema.Builder aBuilder)	Instantiates a new Schema instance from the provided Schema.Builder instance.

Method Summary

Modifier and Type	Method	Description
static Schema.Builder	builder()	Creates a new Schema.Builder for constructing Schema instances.
<T> T	get(String aKey, Class<T> aType)	Gets the value for the .
String	getAlias()
Schema[]	getChildren()
String	getDescription()
Throwable	getException()
int	getHash()
String	getIdentifier()
String	getKey()
<T> T	getOr(String aKey, Class<T> aType, T aValue)	Gets the or.
String	getStereotype()
Class<?>	getType()
Object	getValue()
protected void	init(String aAlias, String aIdentifier, Class<?> aType)	Initializes the Schema with the given parameters, in case of being null, the according values are derived by internal logic.
static String	toInstanceId(Object aObj)	Derives a simple instance identifier String from the simple class's name of the provided instance.
String	toLabel()	Determines a stable label for this schema.
String	toNotation(SchemaNotation aNotation)	Renders this Schema using the given SchemaNotation's SchemaVisitor.
static String	toSimpleInstanceId(Object aObj)	Derives a simple instance identifier String from the simple class's name of the provided instance.
String	toString()
<T> T	visit(SchemaVisitor<T> aVisitor)	Applies the given SchemaVisitor to this Schema.

Methods inherited from class HashMap

clear, clone, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, entrySet, forEach, get, getOrDefault, isEmpty, keySet, merge, newHashMap, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size, values

Methods inherited from class AbstractMap

equals, hashCode

Methods inherited from class Object

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

Methods inherited from interface org.refcodes.mixin.Clearable

clear

Methods inherited from interface org.refcodes.struct.Containable

size

Methods inherited from interface org.refcodes.mixin.EmptyAccessor

isEmpty

Methods inherited from interface org.refcodes.struct.ImmutableTable.MutableTable

delete, put

Methods inherited from interface org.refcodes.struct.Keys

containsKey, containsValue, get, getOr, keySet, values

Methods inherited from interface org.refcodes.struct.Keys.MutableValues

put

Methods inherited from interface Map

clear, compute, computeIfAbsent, computeIfPresent, containsKey, containsValue, entrySet, equals, forEach, get, getOrDefault, hashCode, isEmpty, keySet, merge, put, putAll, putIfAbsent, remove, remove, replace, replace, replaceAll, size, values

Methods inherited from interface org.refcodes.ontology.Ontology

get, get, get, getOr, getOr, getOr, put

Methods inherited from interface org.refcodes.mixin.ValueAccessor

getValueOr, hasValue

Field Details

HASH_SEPARATOR

public static final char HASH_SEPARATOR

This separator is used to separate the hash code form on object's name.

See Also:

• Constant Field Values

_children

protected Schema[] _children

Optional child schemas representing the nested structure (aggregation). May be null to indicate that no children are present.

Constructor Details

Schema

protected Schema()

Instantiates a new schema.

Schema

protected Schema(Schema.Builder aBuilder)

Instantiates a new Schema instance from the provided Schema.Builder instance.

The builder's options are applied, then derived defaults for identifier, alias, and type are initialized if not explicitly provided.

Parameters:

aBuilder - The builder instance from which to populate Schema instance.

Method Details

init

protected void init(String aAlias,
 String aIdentifier,
 Class<?> aType)

Initializes the Schema with the given parameters, in case of being null, the according values are derived by internal logic.

Parameters:

aAlias - The alias for of the Schema, if null it is derived by internal logic.

aIdentifier - The identifier for the Schema, if null it is derived by internal logic.

aType - The type described by the Schema, if null it is derived by internal logic.

getIdentifier

public String getIdentifier()

Specified by:

getIdentifier in interface org.refcodes.mixin.IdentifierAccessor

getAlias

public String getAlias()

Specified by:

getAlias in interface org.refcodes.mixin.AliasAccessor

getKey

public String getKey()

Specified by:

getKey in interface org.refcodes.mixin.KeyAccessor<String>

getType

public Class<?> getType()

Specified by:

getType in interface org.refcodes.mixin.TypeAccessor

getValue

public Object getValue()

Specified by:

getValue in interface org.refcodes.mixin.ValueAccessor<Object>

getHash

public int getHash()

If the hash is not explicitly set, -1 is returned.

Specified by:

getHash in interface org.refcodes.mixin.HashAccessor

getStereotype

public String getStereotype()

Specified by:

getStereotype in interface org.refcodes.mixin.StereotypeAccessor<String>

getException

public Throwable getException()

Specified by:

getException in interface org.refcodes.exception.ExceptionAccessor<Throwable>

getDescription

public String getDescription()

Specified by:

getDescription in interface org.refcodes.mixin.DescriptionAccessor

getChildren

public Schema[] getChildren()

Specified by:

getChildren in interface org.refcodes.mixin.ChildrenAccessor<Schema[]>

get

public <T> T get(String aKey,
 Class<T> aType)

Gets the value for the .

Type Parameters:

T - the generic type

Parameters:

aKey - the key

aType - the type

Returns:

the t

getOr

public <T> T getOr(String aKey,
 Class<T> aType,
 T aValue)

Gets the or.

Type Parameters:

T - the generic type

Parameters:

aKey - the key

aType - the type

aValue - the value

Returns:

the or

toLabel

public String toLabel()

Determines a stable label for this schema.

The label is derived in this order: identifier (without the trailing '@hash' part), type simple name, alias, key, and finally the computed identifier.

Returns:

the derived label

visit

public <T> T visit(SchemaVisitor<T> aVisitor)

Applies the given SchemaVisitor to this Schema.

The SchemaVisitor decides how to traverse the Schema and its children and returns a consolidated result of the traversal.

Type Parameters:

T - The produced result type

Parameters:

aVisitor - The SchemaVisitor to apply

Returns:

The result produced by the visitor

toNotation

public String toNotation(SchemaNotation aNotation)

Renders this Schema using the given SchemaNotation's SchemaVisitor.

Parameters:

aNotation - A @link SchemaNotation}'s SchemaVisitor producing a textual representation

Returns:

The rendered notation

toString

public String toString()

Overrides:

toString in class AbstractMap<String,Object>

toInstanceId

public static String toInstanceId(Object aObj)

Derives a simple instance identifier String from the simple class's name of the provided instance.

Parameters:

aObj - The instance from which to retrieve the simple instance ID String.

Returns:

The derived instance's ID.

toSimpleInstanceId

public static String toSimpleInstanceId(Object aObj)

Derives a simple instance identifier String from the simple class's name of the provided instance.

Parameters:

aObj - The instance from which to retrieve the simple instance ID String.

Returns:

The derived instance's ID.

builder

public static Schema.Builder builder()

Creates a new Schema.Builder for constructing Schema instances.

Returns:

A new builder instance.