com.goldencode.p2j.persist.orm

Class DmoMetadataManager

java.lang.Object

com.goldencode.p2j.persist.orm.DmoMetadataManager

public class DmoMetadataManager
extends java.lang.Object

This manager implements two services:

1. Collects and provides meta information on DMO structures. All DMOs encountered during execution of a 4GL program is required to register with this manager using registerDmo(Class). This method will analyze the class and build an internal data structure that will provide metadata information at request, including:
   • the attributes of the legacy table;
   • the list of properties and attributes of legacy fields they are mapping;
   • the list and attributes of legacy indexes;
   • the list and attributes of relations between tables, as they were detected at conversion time.
2. Based on the information above, the manager is able to construct and will provide at request DDL statements for temp-tables.
   NOTE: A single dialect is expected (usually H2). The DDLs for creation and drop of the table along with its indexes are created simultaneously and are cached locally.

Field Summary

Fields

Modifier and Type	Field and Description
private static DmoMeta[]	byId The DmoMeta ordered by their unique ids.
private static CentralLogger	LOG Logger
private static java.lang.String	pkgroot Cached value of the base package name for all DMOs.
private static java.lang.String	PKGROOT Relative directory path for application package root
private static java.util.IdentityHashMap<java.lang.Class<?>,DmoMeta>	pojoMap Holds the mapping from POJO types to their pair DmoMeta structure.
private static java.util.Map<java.lang.String,DmoMeta>	registry The DMO registry.
private static java.util.Map<java.lang.String,java.util.Map<java.lang.String,DmoMeta>>	simpleRegistry The short-name registry.

Constructor Summary

Constructors

Constructor and Description
DmoMetadataManager()

Method Summary

Modifier and Type	Method and Description
static DmoMeta	byPojoClass(java.lang.Class<?> pojoClass) Reverse lookup of a specific DmoMeta by its POJO class type.
static void	deregisterDmos(java.lang.String... classNames) This removes given a set of dynamic DMO from registry.
static java.lang.Class<? extends DataModelObject>	getAnnotatedInterface(java.lang.Class<? extends DataModelObject> dmoIface) Searches and returns the super-interface DataModelObject that has the Table annotation.
static java.lang.String	getDmoBasePackage() Get the base package name for all DMOs.
static java.lang.Class<? extends DataModelObject>	getDmoIface(java.lang.Class<?> bufferCls) Get the DMO interface associated with the given buffer class.
static DmoMeta	getDmoInfo(java.lang.Class<?> dmo) Searches for a DmoMeta for a specific alias in the list of all known aliases.
static DmoMeta	getDmoInfo(int dmoId) Obtain the DmoMeta of a DMO/table based on its unique id.
static DmoMeta	getDmoInfo(java.lang.String dmoName) Searches for a DmoMeta for a specific alias in the list of all known aliases.
static DmoMeta	getDmoInfo(java.lang.String dmoName, java.lang.String schema) Searches for a DmoMeta for a specific alias in the list of all known aliases.
static java.lang.Class<? extends DataModelObject>	getDMOInterface(java.lang.Class<? extends Record> dmoClass) Deprecated.
static java.util.Set<java.lang.String>	getDmoInterfaces(java.lang.String pathPrefix) Filters and returns a set of interface names from a specified package.
static java.util.Map<java.lang.String,P2JIndexComponent>	getIndexedCharacterColumns(Database database, java.lang.String table) Deprecated.
static RelationInfo	getRelation(java.lang.Class<? extends DataModelObject> localIface, java.lang.Class<? extends DataModelObject> foreignIface) Deprecated.
private static java.lang.String	getSchema(java.lang.Class<?> aClass) Extracts the schema from a DMO class name.
static java.util.Iterator<RelationInfo>	inverseRelations(java.lang.Class<? extends DataModelObject> iface) Deprecated.
static boolean	isLeadingIndexComponent(java.lang.Class<? extends DataModelObject> dmo, java.lang.String property) Deprecated. use DmoMeta.isLeadingIndexComponent(String).
static boolean	isSchemaMatch(java.lang.Class<? extends DataModelObject> ifc1, java.lang.Class<? extends DataModelObject> ifc2) Check if the two DMO interfaces have the same schema.
static void	putDynamicRelation(RelationInfo info) Add an object which describes a foreign relation from one table to another at server runtime (as opposed to relations detected at conversion stage).
static DmoMeta	registerDmo(java.lang.Class<? extends DataModelObject> dmoIface) Gather information for a DMO.
static DmoMeta	registerDmo(java.lang.Class<? extends DataModelObject> dmoIface, java.util.function.Consumer<DmoClass> assembleCallback) Gather information for a DMO.
static java.util.Iterator<RelationInfo>	relations(java.lang.Class<? extends DataModelObject> iface) Deprecated. use DmoMeta.relations().

Methods inherited from class java.lang.Object

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

Field Detail

PKGROOT

private static final java.lang.String PKGROOT

Relative directory path for application package root

See Also:

Constant Field Values

registry

private static final java.util.Map<java.lang.String,DmoMeta> registry

The DMO registry. The keys are full-name of DMO interfaces and implementation classes. Since these include the schema, there will not be any collisions.

simpleRegistry

private static final java.util.Map<java.lang.String,java.util.Map<java.lang.String,DmoMeta>> simpleRegistry

The short-name registry. The keys are the simple name of the DMO implementation class. Since these do not reflect their schema, this is needed as a second level map.

pojoMap

private static final java.util.IdentityHashMap<java.lang.Class<?>,DmoMeta> pojoMap

Holds the mapping from POJO types to their pair DmoMeta structure.

byId

private static DmoMeta[] byId

The DmoMeta ordered by their unique ids. Allocate a minimum amount of space sufficient for basic projects. If there are more DMOs the array will be resized as needed (incrementally, by 150%).

LOG

private static final CentralLogger LOG

Logger

pkgroot

private static java.lang.String pkgroot

Cached value of the base package name for all DMOs. Uses lazy initialization.

Constructor Detail

DmoMetadataManager

public DmoMetadataManager()

Method Detail

getDmoBasePackage

public static java.lang.String getDmoBasePackage()

Get the base package name for all DMOs.

Returns:

Base package name.

getDmoIface

public static java.lang.Class<? extends DataModelObject> getDmoIface(java.lang.Class<?> bufferCls)

Get the DMO interface associated with the given buffer class.

Parameters:

bufferCls - The buffer class

Returns:

The DMO interface

isSchemaMatch

public static boolean isSchemaMatch(java.lang.Class<? extends DataModelObject> ifc1,
                                    java.lang.Class<? extends DataModelObject> ifc2)

Check if the two DMO interfaces have the same schema. This check is compatible and used for lookup of the master buffer/temp-table, when resolving a shared buffer/temp-table.

Parameters:

ifc1 - The first DMO interface.

ifc2 - The second DMO interface.

Returns:

true if the signature is the same.

registerDmo

public static DmoMeta registerDmo(java.lang.Class<? extends DataModelObject> dmoIface)

Gather information for a DMO. The aClass and it super interfaces are analyzed and, if DMO annotation are found, they are stored for later use.

Parameters:

dmoIface - The interface to be analyzed.

Returns:

The {code DmoMeta} structure associated with the requested interface. To obtain the super interface use the DmoMeta.getAnnotatedInterface().

Throws:

java.lang.NullPointerException - if dmoIface is null.

java.lang.IllegalArgumentException - if dmoIface is null or neither dmoIface and none of its super interfaces are annotated as DMO or @Table annotation is not present

registerDmo

public static DmoMeta registerDmo(java.lang.Class<? extends DataModelObject> dmoIface,
                                  java.util.function.Consumer<DmoClass> assembleCallback)

Gather information for a DMO. The aClass and it super interfaces are analyzed and, if DMO annotation are found, they are stored for later use.

Parameters:

dmoIface - The interface to be analyzed.

assembleCallback - Callback method to use after assembling implementation.

Returns:

The {code DmoMeta} structure associated with the requested interface. To obtain the super interface use the DmoMeta.getAnnotatedInterface().

Throws:

java.lang.NullPointerException - if dmoIface is null.

java.lang.IllegalArgumentException - if dmoIface is null or neither dmoIface and none of its super interfaces are annotated as DMO or @Table annotation is not present

getDMOInterface

@Deprecated
public static java.lang.Class<? extends DataModelObject> getDMOInterface(java.lang.Class<? extends Record> dmoClass)

Deprecated.

Get the DMO interface associated with the given DMO implementation class.

Parameters:

dmoClass - DMO implementation class.

Returns:

DMO interface.

Throws:

java.lang.IllegalArgumentException - if any of its interfaces is recognized as a valid DMO interface.

deregisterDmos

public static void deregisterDmos(java.lang.String... classNames)

This removes given a set of dynamic DMO from registry.

Parameters:

classNames - An array of class names to be deregistered.

byPojoClass

public static DmoMeta byPojoClass(java.lang.Class<?> pojoClass)

Reverse lookup of a specific DmoMeta by its POJO class type.

Parameters:

pojoClass - The POJO type to be used as key. If teh specific POJO

Returns:

The DmoMeta of the DMO which declared the pojoClass as its POJO type.

getDmoInfo

public static DmoMeta getDmoInfo(java.lang.String dmoName,
                                 java.lang.String schema)

Searches for a DmoMeta for a specific alias in the list of all known aliases.

Parameters:

dmoName - The name of the alias to be located. May be a full-path DMO, DMO implementation, or simple name of DMO, DMO implementation in which case the schema parameter is used for disambiguate the entity.

schema - The schema of the database. This is used to disambiguate short-names entities.

Returns:

The DmoMeta structure corresponding to dmoName alias, or null if information on this alias is not available.

getDmoInfo

public static DmoMeta getDmoInfo(java.lang.Class<?> dmo)

Searches for a DmoMeta for a specific alias in the list of all known aliases. The method does the best effort to find the right information, regardless the dmo parameter is a DMO interface or an DMO implementation class.

Parameters:

dmo - The DMO class to be located.

Returns:

The DmoMeta structure corresponding to DMO class

Throws:

java.lang.IllegalArgumentException - if the class passed in is not implementing DMO interface or its interface was not registered beforehand.

getDmoInfo

public static DmoMeta getDmoInfo(java.lang.String dmoName)

Searches for a DmoMeta for a specific alias in the list of all known aliases. The method does the best effort to find the right information, regardless the dmo parameter is a DMO interface or an DMO implementation class.

Parameters:

dmoName - The name of the DMO class to be located.

Returns:

The DmoMeta structure corresponding to DMO class

Throws:

java.lang.IllegalArgumentException - if the class passed in is not implementing DMO interface or its interface was not registered beforehand.

getDmoInfo

public static DmoMeta getDmoInfo(int dmoId)

Obtain the DmoMeta of a DMO/table based on its unique id.

Parameters:

dmoId - The unique id of the DMO/table.

Returns:

The DmoMeta for respective DMO/table, or null if dmoId is invalid.

getDmoInterfaces

public static java.util.Set<java.lang.String> getDmoInterfaces(java.lang.String pathPrefix)

Filters and returns a set of interface names from a specified package.

Parameters:

pathPrefix - All registered DMOs will to be 'scanned' and the interfaces whose full name start with this prefix will be returned. The search will exclude the class implementations by looking at their specific suffix.

Returns:

the set of names of the DMO interfaces from the specified package.

getIndexedCharacterColumns

@Deprecated
public static java.util.Map<java.lang.String,P2JIndexComponent> getIndexedCharacterColumns(Database database,
                                                                                                       java.lang.String table)
                                                                                                throws PersistenceException

Deprecated.

For the given schema and DMO interface, get the map of indexed character column names to P2JIndexComponent instances which describe their use in individual indexes.

They are read directly from the specified table, using a IndexMetadataCollector.queryIndexData(Session, String) call.

Parameters:

database - Database information object.

table - backing table name.

Returns:

Unmodifiable map.

Throws:

PersistenceException - if there is an error querying index information from the JDBC driver.

isLeadingIndexComponent

@Deprecated
public static boolean isLeadingIndexComponent(java.lang.Class<? extends DataModelObject> dmo,
                                                          java.lang.String property)

Deprecated. use DmoMeta.isLeadingIndexComponent(String).

Determine whether the given DMO property represents the leading component of any index on the table represented by the given buffer.

Parameters:

dmo - The DMO of a table associated with the property.

property - DMO property to be tested.

Returns:

true if property is a leading index component; else false.

relations

@Deprecated
public static java.util.Iterator<RelationInfo> relations(java.lang.Class<? extends DataModelObject> iface)

Deprecated. use DmoMeta.relations().

Get an iterator on all foreign relation descriptors for the DMO specified by the given schema and interface. The resulting iterator returns RelationInfo instances, each of which describes a foreign key relation from the specified DMO to another.

Parameters:

iface - DMO interface.

Returns:

Iterator on foreign relation descriptors.

Throws:

java.lang.IllegalArgumentException - if either the schema or iface parameters are not recognized.

java.lang.IllegalStateException - if P2J_HOME is not defined; if there is any error parsing the DMO index document.

inverseRelations

@Deprecated
public static java.util.Iterator<RelationInfo> inverseRelations(java.lang.Class<? extends DataModelObject> iface)

Deprecated.

Get an iterator on all inverse foreign relation descriptors for the DMO specified by the given schema and interface. The resulting iterator returns RelationInfo instances, each of which describes a foreign key relation to the specified DMO from another.

Parameters:

iface - DMO interface.

Returns:

Iterator on inverse foreign relation descriptors.

Throws:

java.lang.IllegalArgumentException - if either the schema or iface parameters are not recognized.

java.lang.IllegalStateException - if P2J_HOME is not defined; if there is any error parsing the DMO index document.

getRelation

@Deprecated
public static RelationInfo getRelation(java.lang.Class<? extends DataModelObject> localIface,
                                                   java.lang.Class<? extends DataModelObject> foreignIface)

Deprecated.

Retrieve an object which describes the foreign relation between two tables.

Parameters:

localIface - DMO interface for the local table.

foreignIface - DMO interface for the foreign table.

Returns:

Object which describes the relation, or null if no such relation exists. Note that a null return does not necessarily indicate that the inverse relation does not exist. This can be determined by invoking this method with the localIface and foreignIface parameters inverted.

putDynamicRelation

public static void putDynamicRelation(RelationInfo info)

Add an object which describes a foreign relation from one table to another at server runtime (as opposed to relations detected at conversion stage).

Parameters:

info - Relation descriptor.

getAnnotatedInterface

public static java.lang.Class<? extends DataModelObject> getAnnotatedInterface(java.lang.Class<? extends DataModelObject> dmoIface)

Searches and returns the super-interface DataModelObject that has the Table annotation.

Parameters:

dmoIface - The interface to be analysed.

Returns:

the super-interface DataModelObject that has the Table annotation or null if no such interface can be found.

getSchema

private static java.lang.String getSchema(java.lang.Class<?> aClass)

Extracts the schema from a DMO class name. It is computed as a very last package path part from the class/interface full name.

Parameters:

aClass - the DMO class or interface.

Returns:

the schema name.