org.jpox.metadata
Class MetaDataUtils

java.lang.Object
  org.jpox.metadata.MetaDataUtils

public class MetaDataUtils
extends java.lang.Object

Utilities needed for the processing of MetaData.

Version:

$Revision: 1.35 $

Field Summary

protected static Localiser

LOCALISER

Constructor Summary

protected

MetaDataUtils() Protected constructor to prevent outside instantiation

Method Summary

java.lang.String[]	getImplementationNamesForReferenceField(AbstractPropertyMetaData fmd, DatastoreFieldRole role, ClassLoaderResolver clr) Convenience method to return the class names of the available implementation types for an interface/Object field, given its required role.
static MetaDataUtils	getInstance() Gets an instance of MetaDataUtils
java.util.List	getOrderedClassNamesFromFileList(java.net.URL[] metaDataFileURLs, java.util.Map classToMetaDataMap) Utility to return a list of classes declared in provided metadata files.
java.lang.String[]	getValuesForCommaSeparatedAttribute(java.lang.String attr) Convenience method that splits a comma-separated list of values into a String array (removing whitespace).
boolean	isValidPrimaryKeyClass(java.lang.Class pkClass, AbstractClassMetaData cmd, ClassLoaderResolver clr, int noOfPkFields) Utility to check if a primary-key class is valid.
boolean	storesFCO(AbstractPropertyMetaData fmd, ClassLoaderResolver clr) Convenience method that returns if a field stores a First-Class object (FCO).

Methods inherited from class java.lang.Object

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

Field Detail

LOCALISER

protected static final Localiser LOCALISER

Constructor Detail

MetaDataUtils

protected MetaDataUtils()

Protected constructor to prevent outside instantiation

Method Detail

getInstance

public static MetaDataUtils getInstance()

Gets an instance of MetaDataUtils

Returns:

a singleton instance of MetaDataUtils

getOrderedClassNamesFromFileList

public java.util.List getOrderedClassNamesFromFileList(java.net.URL[] metaDataFileURLs,
                                                       java.util.Map classToMetaDataMap)
                                                throws java.lang.Exception

Utility to return a list of classes declared in provided metadata files. The list of classes are ordered so that all superclasses occur before their subclasses. Additionally populates the provided map with entries mapping the class names to the JDO MetaData file name that the class was found in. Used by SchemaTool.

Parameters:

metaDataFileURLs - The list of JDO metadata file names.

classToMetaDataMap - A Map that will be populated mapping class name to the MetaData file name. This argument can be null.

Returns:

An ordered list of class name strings.

Throws:

java.lang.Exception

isValidPrimaryKeyClass

public boolean isValidPrimaryKeyClass(java.lang.Class pkClass,
                                      AbstractClassMetaData cmd,
                                      ClassLoaderResolver clr,
                                      int noOfPkFields)

Utility to check if a primary-key class is valid. Will throw a InvalidPrimaryKeyException if it is invalid, otherwise returning true.

Parameters:

pkClass - The Primary Key class

cmd - AbstractClassMetaData for the PersistenceCapable class

clr - the ClassLoaderResolver

noOfPkFields - Number of primary key fields

Returns:

Whether it is valid

storesFCO

public boolean storesFCO(AbstractPropertyMetaData fmd,
                         ClassLoaderResolver clr)

Convenience method that returns if a field stores a First-Class object (FCO).

Parameters:

fmd - MetaData for the field

clr - ClassLoaderResolver resolver

Returns:

Whether it stores a FCO

getValuesForCommaSeparatedAttribute

public java.lang.String[] getValuesForCommaSeparatedAttribute(java.lang.String attr)

Convenience method that splits a comma-separated list of values into a String array (removing whitespace).

Parameters:

attr - The attribute value

Returns:

The string components

getImplementationNamesForReferenceField

public java.lang.String[] getImplementationNamesForReferenceField(AbstractPropertyMetaData fmd,
                                                                  DatastoreFieldRole role,
                                                                  ClassLoaderResolver clr)

Convenience method to return the class names of the available implementation types for an interface/Object field, given its required role. Removes all duplicates from the list.

Parameters:

fmd - MetaData for the field

role - The role of the field

clr - the ClassLoaderResolver

Returns:

Names of the classes of the possible implementations of this interface/Object

Throws:

javax.jdo.JDOUserException - if no implementation types are found for the reference type field