org.openjdk.jmc.flightrecorder.rules.jdk.util

Class DefaultIItemResultSet

java.lang.Object

org.openjdk.jmc.flightrecorder.rules.jdk.util.DefaultIItemResultSet

All Implemented Interfaces:

IItemResultSet

final class DefaultIItemResultSet
extends java.lang.Object
implements IItemResultSet

The default implementation of an IItemResultSet.

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.List<IAggregator<?,?>>	aggregators
private java.util.List<IAttribute<?>>	attributes
private int	cursor
private java.util.ArrayList<java.lang.Object[]>	data
private java.util.Map<java.lang.String,ColumnInfo>	info
private IItemQuery	query

Constructor Summary

Constructors

Constructor and Description
DefaultIItemResultSet(IItemCollection items, IItemQuery query)

Method Summary

Modifier and Type	Method and Description
private void	calculateData(IItemCollection input)
java.util.Map<java.lang.String,ColumnInfo>	getColumnMetadata() Returns the column metadata for the result set.
private static java.lang.Object	getFirstNonNull(IItemCollection items, IAttribute<?> attribute) Returns the first encountered non-null attribute value, or null if no non-null value could be found.
private int	getNoOfColumns()
IItemQuery	getQuery() Returns the query used to create the result set.
java.lang.Object	getValue(int column) Returns the value for the specified column, at the current row.
private void	initializeMetadata()
private java.lang.Object[]	newRow()
boolean	next() Advances the cursor to the next row in the result set.

Methods inherited from class java.lang.Object

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

Field Detail

query

private final IItemQuery query

attributes

private final java.util.List<IAttribute<?>> attributes

aggregators

private final java.util.List<IAggregator<?,?>> aggregators

info

private final java.util.Map<java.lang.String,ColumnInfo> info

data

private final java.util.ArrayList<java.lang.Object[]> data

cursor

private int cursor

Constructor Detail

DefaultIItemResultSet

DefaultIItemResultSet(IItemCollection items,
                      IItemQuery query)

Method Detail

calculateData

private void calculateData(IItemCollection input)

getFirstNonNull

private static java.lang.Object getFirstNonNull(IItemCollection items,
                                                IAttribute<?> attribute)

Returns the first encountered non-null attribute value, or null if no non-null value could be found.

Parameters:

items - the items to search.

attribute - the attribute to look for.

Returns:

the first value found.

newRow

private java.lang.Object[] newRow()

initializeMetadata

private void initializeMetadata()

getQuery

public IItemQuery getQuery()

Description copied from interface: IItemResultSet

Returns the query used to create the result set.

Specified by:

getQuery in interface IItemResultSet

Returns:

the query used to create the result set.

getValue

public java.lang.Object getValue(int column)
                          throws ItemResultSetException

Description copied from interface: IItemResultSet

Returns the value for the specified column, at the current row.

Specified by:

getValue in interface IItemResultSet

Parameters:

column - the column for which to return the value.

Returns:

value for the specified column, at the current row.

Throws:

ItemResultSetException - if there was a problem reading the value, such as the cursor not being at a value, the column not existing etc.

getNoOfColumns

private int getNoOfColumns()

getColumnMetadata

public java.util.Map<java.lang.String,ColumnInfo> getColumnMetadata()

Description copied from interface: IItemResultSet

Returns the column metadata for the result set. Useful for finding out what column an attribute or an aggregator is mapping to.

Specified by:

getColumnMetadata in interface IItemResultSet

Returns:

the column metadata.

next

public boolean next()

Description copied from interface: IItemResultSet

Advances the cursor to the next row in the result set. Returns true if there is still more rows, and false if the end has been reached.

Specified by:

next in interface IItemResultSet

Returns:

true if there is still more rows, and false if the end has been reached.