uk.ac.starlink.gbin

Class DefaultGbinTableProfile

java.lang.Object

uk.ac.starlink.gbin.DefaultGbinTableProfile

All Implemented Interfaces:

GbinTableProfile

public class DefaultGbinTableProfile
extends java.lang.Object
implements GbinTableProfile

Default implementation of GbinTableProfile.

Since:

3 Sep 2015

Constructor Summary

Constructors

Constructor and Description
DefaultGbinTableProfile() Constructs a profile with default configuration.
DefaultGbinTableProfile(java.lang.Class<?>[] simpleClasses, java.lang.Class<?>[] stringClasses, java.lang.Class<?>[] ignoreClasses) Constructs a profile with explicit configuration.

Method Summary

Modifier and Type	Method and Description
static <T> Representation<T>	createIdentityRepresentation(java.lang.Class<T> clazz, boolean isColumn) Returns a representation that uses the input values unchanged.
Representation<?>	createRepresentation(java.lang.Class<?> clazz) Returns an object which can represent a particular data type returned from an accessor method of a GBIN object (or one of its descendants).
static Representation<java.lang.String>	createStringColumnRepresentation(java.lang.Class<?> clazz) Returns a representation that maps its input values to strings using their toString method, and uses the result like a column.
java.lang.String[]	getIgnoreMethodDeclaringClasses() This implementation returns the classnames gaia.cu1.tools.dm.GaiaRoot and gaia.cu1.tools.dmimpl.GaiaRootImpl.
java.lang.String[]	getIgnoreMethodNames() Returns the list of method names to ignore when coming up with a list of columns for an object.
java.lang.String	getNameSeparator() Returns the separation string used to delimit parts of column hierarchical names.
boolean	isHierarchicalNames() Indicates whether column names in the output table should be forced to reflect the compositional hierarchy of their position in the element objects.
boolean	isReadMeta() Indicates whether non-essential metadata is read from the GBIN file.
boolean	isSortedMethods() Indicates whether object accessor method names should be sorted alphabetically when producing the column sequence.
boolean	isTestMagic() Indicates whether the magic number is read from GBIN files before attempting to turn them into tables.

Methods inherited from class java.lang.Object

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

Constructor Detail

DefaultGbinTableProfile

public DefaultGbinTableProfile()

Constructs a profile with default configuration.

DefaultGbinTableProfile

public DefaultGbinTableProfile(java.lang.Class<?>[] simpleClasses,
                               java.lang.Class<?>[] stringClasses,
                               java.lang.Class<?>[] ignoreClasses)

Constructs a profile with explicit configuration. Any classes not referred to in the supplied lists, apart from primitive classes which are always used, will be treated as elements in the object hierarchy and descended into recursively.

Parameters:

simpleClasses - list of scalar Object subclasses that are suitable contents of a column as they stand

stringClasses - list of scalar Object subclasses that can be used as string contents of a column by invoking their toString method

ignoreClasses - classes which should be ignored completely when converting to a table

Method Detail

isReadMeta

public boolean isReadMeta()

Description copied from interface: GbinTableProfile

Indicates whether non-essential metadata is read from the GBIN file. This includes amongst other things the row count and a description of the data. Because of the way GBIN reading works, reading metadata requires acquisition of a new InputStream (it can't be done using the same stream that reads the data objects) so it may be expensive.

Specified by:

isReadMeta in interface GbinTableProfile

Returns:

true to attempt to read metadata where possible

isTestMagic

public boolean isTestMagic()

Description copied from interface: GbinTableProfile

Indicates whether the magic number is read from GBIN files before attempting to turn them into tables. It's probably a good idea to set this true, but there may be GBIN variants for which the magic number testing supplied gives false negatives, in which case you'd want to turn it off.

Specified by:

isTestMagic in interface GbinTableProfile

Returns:

true if you want magic number mismatch to cause read failure

isHierarchicalNames

public boolean isHierarchicalNames()

Description copied from interface: GbinTableProfile

Indicates whether column names in the output table should be forced to reflect the compositional hierarchy of their position in the element objects. If set true, columns will have names like "Astrometry_Alpha", if false they may just be called "Alpha". In case of name duplication however, the hierarchical form is always used.

Specified by:

isHierarchicalNames in interface GbinTableProfile

Returns:

true to force use of hierarchical column names

getNameSeparator

public java.lang.String getNameSeparator()

Description copied from interface: GbinTableProfile

Returns the separation string used to delimit parts of column hierarchical names. If the value is "_" you may see column names like "Astrometry_Alpha". An empty string is permissible too.

Specified by:

getNameSeparator in interface GbinTableProfile

Returns:

column hierarchical name separator string

isSortedMethods

public boolean isSortedMethods()

Description copied from interface: GbinTableProfile

Indicates whether object accessor method names should be sorted alphabetically when producing the column sequence. Otherwise get* method names will be used in whatever sequence reflection provides them in, which according to the Class.getMethods() javadocs is "not sorted and are not in any particular order".

Specified by:

isSortedMethods in interface GbinTableProfile

Returns:

true to sort method names alphabetically

getIgnoreMethodNames

public java.lang.String[] getIgnoreMethodNames()

Description copied from interface: GbinTableProfile

Returns the list of method names to ignore when coming up with a list of columns for an object. Any methods matching strings in the return value will not be used to generate columns in an output table. Only public instance methods of the form getXxx() or isXxx() are used in any case. The restrictions determined by GbinTableProfile.getIgnoreMethodDeclaringClasses() also apply.

Specified by:

getIgnoreMethodNames in interface GbinTableProfile

Returns:

list of accessor method names to ignore

getIgnoreMethodDeclaringClasses

public java.lang.String[] getIgnoreMethodDeclaringClasses()

This implementation returns the classnames gaia.cu1.tools.dm.GaiaRoot and gaia.cu1.tools.dmimpl.GaiaRootImpl. This behaviour addresses an issue that shows up in versions of GaiaTools 19.4.*, >=20.1.0 and >=21.0.0, where invoking the GaiaRoot getSolutionId method throws an exception.

The getSolutionId method is present in all GaiaRoot subtypes, but in some cases no solutionId field is defined. In that circumstance older GaiaTools versions simply returned a dummy value Long.MIN_VALUE, but more recent versions throw an exception, which caused the GbinStarTable construction to fail.

Avoiding attempts to turn the getSolutionId method into a GbinStarTable column can be done by checking whether the class declaring the method is GaiaRoot/GaiaRootImpl, as provided here. This fix was suggested by Alexander Hutton (CU1).

Specified by:

getIgnoreMethodDeclaringClasses in interface GbinTableProfile

Returns:

list of declaring classes whose methods are to be ignored

createRepresentation

public Representation<?> createRepresentation(java.lang.Class<?> clazz)

Description copied from interface: GbinTableProfile

Returns an object which can represent a particular data type returned from an accessor method of a GBIN object (or one of its descendants). If null is returned, the object should not appear in the output table at all.

Specified by:

createRepresentation in interface GbinTableProfile

Parameters:

clazz - return type of an accessor method

Returns:

object indicating how accessed objects should appear in the output table; null to truncate the hierarchy here

createIdentityRepresentation

public static <T> Representation<T> createIdentityRepresentation(java.lang.Class<T> clazz,
                                                                 boolean isColumn)

Returns a representation that uses the input values unchanged.

Parameters:

clazz - input type

isColumn - whether this represents a column or not

Returns:

representation of column or structured object

createStringColumnRepresentation

public static Representation<java.lang.String> createStringColumnRepresentation(java.lang.Class<?> clazz)

Returns a representation that maps its input values to strings using their toString method, and uses the result like a column.

Parameters:

clazz - input type

Returns:

representation of column