Apache Derby Database Engine and Embedded JDBC Driver 10.17.1.0 · org.apache.derby.impl.store.access.btree.BranchRow

Modifier and Type	Field and Description
private DataValueDescriptor[]	branchrow The array of object to be used as the row.
public static final long	DUMMY_PAGE_NUMBER

Access	Constructor and Description
private	BranchRow() Constuctor for creating an "empty" BranchRow template, suitable for reading in a branchRow from disk.
private	BranchRow(Transaction rawtran, BTree btree)

Method Summary

Modifier and Type	Method and Description
public BranchRow	createBranchRowFromOldBranchRow(long childpageno) Create a new branch row, given a old branch row and a new child page.
public static BranchRow	createBranchRowFromOldLeafRow(DataValueDescriptor[] leafrow, long childpageno) Create a new branch row, given a old leaf row and a new child page.
public static BranchRow	createEmptyTemplate(Transaction rawtran, BTree btree) Create an empty branch row template suitable for reading branch rows in from disk.
private SQLLongint	Returns: The child page object. getChildPage() Accessor for the child page field of the branch row.
protected DataValueDescriptor[]	Returns: The branch row object array. getRow() Return the branch row.
protected void	setPageNumber(long the new page number. page_number) Set the page number field of the branch row to a new value.
public String	toString() Overrides java.lang.Object.toString. Returns a string representation of the object.

Inherited from java.lang.Object:: clone equals finalize getClass hashCode notify notifyAll wait wait wait

branchrow	back to summary
private DataValueDescriptor[] branchrow The array of object to be used as the row.

DUMMY_PAGE_NUMBER	back to summary
public static final long DUMMY_PAGE_NUMBER

BranchRow	back to summary
private BranchRow() Constuctor for creating an "empty" BranchRow template, suitable for reading in a branchRow from disk.

BranchRow	back to summary
private BranchRow(Transaction rawtran, BTree btree) throws StandardException

Method Detail

createBranchRowFromOldBranchRow	back to summary
public BranchRow createBranchRowFromOldBranchRow(long childpageno) Create a new branch row, given a old branch row and a new child page. Used by BranchControlRow to manufacture new branch rows when splitting or growing the tree. There is no way to "copy" values of a template row, so this class just stores a reference to each of the columns of the Indexable row passed in. This is ok as all usages of this class when instantiated this way, have an old branch row from which they are creating a new branch row with the same key values, and a different child page number. WARNING - this branch row is only valid while the old branch row is valid, as it contains references to the columns of the old branch row. So use of the row should only provide read-only access to the objects of the old branch row which are referenced.

createBranchRowFromOldBranchRow

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public BranchRow createBranchRowFromOldBranchRow(long childpageno)

Create a new branch row, given a old branch row and a new child page. Used by BranchControlRow to manufacture new branch rows when splitting or growing the tree. There is no way to "copy" values of a template row, so this class just stores a reference to each of the columns of the Indexable row passed in. This is ok as all usages of this class when instantiated this way, have an old branch row from which they are creating a new branch row with the same key values, and a different child page number. WARNING - this branch row is only valid while the old branch row is valid, as it contains references to the columns of the old branch row. So use of the row should only provide read-only access to the objects of the old branch row which are referenced.

createBranchRowFromOldLeafRow	back to summary
public static BranchRow createBranchRowFromOldLeafRow(DataValueDescriptor[] leafrow, long childpageno) Create a new branch row, given a old leaf row and a new child page. Used by LeafControlRow to manufacture new branch rows when splitting or growing the tree. There is no way to "copy" values of a template row, so this class just stores a referece to the Indexable row passed in. This is ok as all usages of this class when instantiated this way, have an old leaf row from which they are creating a new branch row with the same key values, and a different child page number. WARNING - this branch row is only valid while the old leaf row is valid, as it contains references to the columns of the old leaf row. So use of the row should only provide read-only access to the objects of the old leaf row which are referenced.

createBranchRowFromOldLeafRow

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public static BranchRow createBranchRowFromOldLeafRow(DataValueDescriptor[] leafrow, long childpageno)

Create a new branch row, given a old leaf row and a new child page. Used by LeafControlRow to manufacture new branch rows when splitting or growing the tree. There is no way to "copy" values of a template row, so this class just stores a referece to the Indexable row passed in. This is ok as all usages of this class when instantiated this way, have an old leaf row from which they are creating a new branch row with the same key values, and a different child page number. WARNING - this branch row is only valid while the old leaf row is valid, as it contains references to the columns of the old leaf row. So use of the row should only provide read-only access to the objects of the old leaf row which are referenced.

createEmptyTemplate	back to summary
public static BranchRow createEmptyTemplate(Transaction rawtran, BTree btree) throws StandardException Create an empty branch row template suitable for reading branch rows in from disk. This routine will create newly allocated "empty" objects for every column in the template row. Exceptions StandardException: Standard exception policy.

createEmptyTemplate

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public static BranchRow createEmptyTemplate(Transaction rawtran, BTree btree) throws StandardException

Create an empty branch row template suitable for reading branch rows in from disk. This routine will create newly allocated "empty" objects for every column in the template row.

Exceptions

StandardException:: Standard exception policy.

getChildPage	back to summary
private SQLLongint getChildPage() Accessor for the child page field of the branch row. Returns:SQLLongint The child page object.

getChildPage

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private SQLLongint getChildPage()

Accessor for the child page field of the branch row.

Returns:SQLLongint: The child page object.

getRow	back to summary
protected DataValueDescriptor[] getRow() Return the branch row. Return the DataValueDescriptor array that represents the branch row, for use in raw store calls to fetch, insert, and update. Returns:DataValueDescriptor[] The branch row object array.

getRow

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protected DataValueDescriptor[] getRow()

Return the branch row.

Return the DataValueDescriptor array that represents the branch row, for use in raw store calls to fetch, insert, and update.

Returns:DataValueDescriptor[]: The branch row object array.

setPageNumber	back to summary
protected void setPageNumber(long page_number) Set the page number field of the branch row to a new value. Parameters page_number:long the new page number.

setPageNumber

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protected void setPageNumber(long page_number)

Set the page number field of the branch row to a new value.

Parameters

page_number:long: the new page number.

toString back to summary

toString	back to summary
public String toString() Overrides java.lang.Object.toString. Doc from java.lang.Object.toString. Returns a string representation of the object. Satisfying this method's contract implies a non-`null` result must be returned. Returns:String a string representation of the object

public String toString()

Overrides java.lang.Object.toString.

Doc from java.lang.Object.toString.

Returns a string representation of the object. Satisfying this method's contract implies a non-null result must be returned.

Returns:String: a string representation of the object

public Class BranchRow

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Field Detail

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Method Detail