public class HistorianQueryExecutor extends java.lang.Object implements HistoryQueryExecutor
Constructor and Description |
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HistorianQueryExecutor(Historian historian,
java.util.List<ColumnQueryDefinition> paths,
QueryController controller) |
Modifier and Type | Method and Description |
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protected HistoryNode |
buildRealNode(PathInfo pi,
ColumnQueryDefinition def) |
void |
endReading()
If startReading was called, this function must be called (that is, it should be in a finally
block).
|
java.util.List<? extends HistoryNode> |
getColumnNodes()
Returns the HistoryNodes of this executor.
|
int |
getEffectiveWindowSizeMS()
When "natural" results are requested, this will be called to let the query executors say what they think
"natural" means.
|
boolean |
hasMore()
Returns TRUE if there is more data available to be written on call to processData()
|
protected HistoricalValue |
historicalValue(ResultDataPoint data) |
void |
initialize()
Initializes the query, performing any actions necessary to get the information required to run the query.
|
protected void |
moveForward() |
long |
nextTime()
The timestamp of the next value.
|
long |
processData()
Puts the next value(s) into the appropriate column, returning the latest timestamp loaded, or -1 if no data was
loaded.
|
protected java.lang.String |
standardizePath(QualifiedPath p) |
void |
startReading()
Begins reading data.
|
protected DataTypeClass |
toDataTypeClass(DataType t) |
public HistorianQueryExecutor(Historian historian, java.util.List<ColumnQueryDefinition> paths, QueryController controller)
public void initialize() throws java.lang.Exception
HistoryQueryExecutor
initialize
in interface HistoryQueryExecutor
java.lang.Exception
public java.util.List<? extends HistoryNode> getColumnNodes()
HistoryQueryExecutor
DelegatingHistoryNode
s, which get filled in later.getColumnNodes
in interface HistoryQueryExecutor
public int getEffectiveWindowSizeMS()
HistoryQueryExecutor
getEffectiveWindowSizeMS
in interface HistoryQueryExecutor
protected java.lang.String standardizePath(QualifiedPath p)
public void startReading() throws java.lang.Exception
HistoryQueryExecutor
startReading
in interface HistoryQueryExecutor
java.lang.Exception
protected HistoryNode buildRealNode(PathInfo pi, ColumnQueryDefinition def)
protected DataTypeClass toDataTypeClass(DataType t)
public void endReading()
HistoryQueryExecutor
endReading
in interface HistoryQueryExecutor
public boolean hasMore()
HistoryQueryExecutor
hasMore
in interface HistoryQueryExecutor
protected void moveForward()
public long nextTime()
HistoryQueryExecutor
nextTime
in interface HistoryQueryExecutor
public long processData() throws java.lang.Exception
HistoryQueryExecutor
processData
in interface HistoryQueryExecutor
java.lang.Exception
protected HistoricalValue historicalValue(ResultDataPoint data)