Package com.mckoi.database
Class FilterTable
java.lang.Object
com.mckoi.database.Table
com.mckoi.database.FilterTable
- All Implemented Interfaces:
TableDataSource
- Direct Known Subclasses:
ReferenceTable
,SubsetColumnTable
A table that is a filter for another table. By default, all Table methods
are implemented to call the parent. This class should be used when we
want to implement a Table filter of some kind. For example, a filter
for specific columns, or even rows, etc.
NOTE: For efficiency reasons, this will store SelectableScheme objects generated by the parent like VirtualTable.
- Author:
- Tobias Downer
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Field Summary
FieldsFields inherited from class com.mckoi.database.Table
DEBUG_QUERY
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Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionint
Given a fully qualified variable field name, ie.getCellContents
(int column, int row) Returns an object that represents the information in the given cell in the table.int
Returns the number of columns in the table.Returns the parent Database object.Returns a DataTableDef object that defines the name of the table and the layout of the columns of the table.protected Table
Returns the parent table.getResolvedVariable
(int column) Returns a fully qualified Variable object that represents the name of the column at the given index.int
Returns the number of rows stored in the table.boolean
Returns true if the table has its row roots locked (via the lockRoot(int) method.void
lockRoot
(int lock_key) Locks the root table(s) of this table so that it is impossible to overwrite the underlying rows that may appear in this table.void
printGraph
(PrintStream out, int indent) Prints a graph of the table hierarchy to the stream.Returns an Enumeration of the rows in this table.void
unlockRoot
(int lock_key) Unlocks the root tables so that the underlying rows may once again be used if they are not locked and have been removed.Methods inherited from class com.mckoi.database.Table
all, allColumnMatchesValue, any, columnContainsCell, columnContainsValue, columnMatchesValue, columnMerge, compareCells, Debug, distinct, distinct, dumpTo, emptySelect, exhaustiveSelect, fastFindFieldName, getColumnDefAt, getColumnScheme, getFirstCellContent, getFirstCellContent, getLastCellContent, getLastCellContent, getSingleCellContent, getSingleCellContent, getSystem, getTableAccessState, getTTypeForColumn, getTTypeForColumn, join, orderByColumn, orderByColumn, orderByColumn, orderByColumns, orderedRowList, outside, rangeSelect, selectAll, selectAll, selectFirst, selectLast, selectRange, selectRest, simpleJoin, simpleSelect, singleRowSelect, toMap, toString, union
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Field Details
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parent
The Table we are filtering the columns from.
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Constructor Details
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FilterTable
The Constructor.
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Method Details
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getParent
Returns the parent table. -
getDatabase
Returns the parent Database object.- Specified by:
getDatabase
in classTable
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getColumnCount
public int getColumnCount()Returns the number of columns in the table.- Specified by:
getColumnCount
in classTable
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getRowCount
public int getRowCount()Returns the number of rows stored in the table.- Specified by:
getRowCount
in interfaceTableDataSource
- Specified by:
getRowCount
in classTable
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findFieldName
Given a fully qualified variable field name, ie. 'APP.CUSTOMER.CUSTOMERID' this will return the column number the field is at. Returns -1 if the field does not exist in the table.- Specified by:
findFieldName
in classTable
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getResolvedVariable
Returns a fully qualified Variable object that represents the name of the column at the given index. For example, new Variable(new TableName("APP", "CUSTOMER"), "ID")- Specified by:
getResolvedVariable
in classTable
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getCellContents
Returns an object that represents the information in the given cell in the table. This will generally be an expensive algorithm, so calls to it should be kept to a minimum. Note that the offset between two rows is not necessarily 1.- Specified by:
getCellContents
in interfaceTableDataSource
- Specified by:
getCellContents
in classTable
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rowEnumeration
Returns an Enumeration of the rows in this table. The Enumeration is a fast way of retrieving consequtive rows in the table.- Specified by:
rowEnumeration
in interfaceTableDataSource
- Specified by:
rowEnumeration
in classTable
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getDataTableDef
Returns a DataTableDef object that defines the name of the table and the layout of the columns of the table. Note that for tables that are joined with other tables, the table name and schema for this object become mangled. For example, a table called 'PERSON' joined with a table called 'MUSIC' becomes a table called 'PERSON#MUSIC' in a null schema.- Specified by:
getDataTableDef
in interfaceTableDataSource
- Specified by:
getDataTableDef
in classTable
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lockRoot
public void lockRoot(int lock_key) Locks the root table(s) of this table so that it is impossible to overwrite the underlying rows that may appear in this table. This is used when cells in the table need to be accessed 'outside' the lock. So we may have late access to cells in the table. 'lock_key' is a given key that will also unlock the root table(s). NOTE: This is nothing to do with the 'LockingMechanism' object. -
unlockRoot
public void unlockRoot(int lock_key) Unlocks the root tables so that the underlying rows may once again be used if they are not locked and have been removed. This should be called some time after the rows have been locked.- Specified by:
unlockRoot
in classTable
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hasRootsLocked
public boolean hasRootsLocked()Returns true if the table has its row roots locked (via the lockRoot(int) method.- Specified by:
hasRootsLocked
in classTable
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printGraph
Prints a graph of the table hierarchy to the stream.- Overrides:
printGraph
in classTable
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