gudusoft.gsqlparser.dlineage.dataflow.model

Class StarLinkMatcher

Object

gudusoft.gsqlparser.dlineage.dataflow.model.StarLinkMatcher

public final class StarLinkMatcher
extends Object

Matches the star links and model columns of a relation's sources against one star link of its target, the link a star expansion is publishing. Obtained from Column.starLinkMatcher(int) once per expansion, it decides the matches the analyzer used to decide on the target link's folded display, with the same comparisons: a target link matches a source link or model column under DlineageUtil.sameColumnNormalName(java.lang.String, java.lang.String), and is named by a model column whose folded name equals its own folded display.

Internal contract of the lineage analyzer.

Method Summary

Modifier and Type	Method and Description
boolean	isDisplacedIn(Column source) Whether the star links of source hold another identity's column under this link's folded display: a column the grouping by display would take for this link's, and which, grouped by identity, is a different column (PostgreSQL "Amount" where this link is amount).
boolean	isNamedBy(Column model) Whether model carries exactly this link's name.
Object	key() The key this link is remembered by among the target links that already have an explicit source.
boolean	matches(Column source, int ordinal) Whether the star link at ordinal of source is this link's column.
boolean	matchesColumn(Column model) Whether model is this link's column, compared as the analyzer compared a model name.

Methods inherited from class Object

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

Method Detail

matches

public boolean matches(Column source,
                       int ordinal)

Whether the star link at ordinal of source is this link's column.

matchesColumn

public boolean matchesColumn(Column model)

Whether model is this link's column, compared as the analyzer compared a model name.

isNamedBy

public boolean isNamedBy(Column model)

Whether model carries exactly this link's name.

isDisplacedIn

public boolean isDisplacedIn(Column source)

Whether the star links of source hold another identity's column under this link's folded display: a column the grouping by display would take for this link's, and which, grouped by identity, is a different column (PostgreSQL "Amount" where this link is amount). A star that holds it is not inferred to hold this link's column as well; false while links are grouped by display, and for a label.

key

public Object key()

The key this link is remembered by among the target links that already have an explicit source. A source link is looked up in that set by Column.starLinkKey(int).