Class AbstractBatchedColumnProcessor<T extends Context>
java.lang.Object
com.univocity.parsers.common.processor.core.AbstractBatchedColumnProcessor<T>
- All Implemented Interfaces:
BatchedColumnReader<String>
,ColumnReader<String>
,Processor<T>
- Direct Known Subclasses:
BatchedColumnProcessor
public abstract class AbstractBatchedColumnProcessor<T extends Context>
extends Object
implements Processor<T>, BatchedColumnReader<String>
A
Processor
implementation that stores values of columns in batches. Use this implementation in favor of AbstractColumnProcessor
when processing large inputs to avoid running out of memory.
Values parsed in each row will be split into columns of Strings. Each column has its own list of values.
During the execution of the process, the batchProcessed(int)
method will be invoked after a given number of rows has been processed.
The user can access the lists with values parsed for all columns using the methods getColumnValuesAsList()
,
getColumnValuesAsMapOfIndexes()
and getColumnValuesAsMapOfNames()
.
After batchProcessed(int)
is invoked, all values will be discarded and the next batch of column values will be accumulated.
This process will repeat until there's no more rows in the input.
- See Also:
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Field Summary
FieldsModifier and TypeFieldDescriptionprivate int
private int
private final int
private final ColumnSplitter<String>
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Constructor Summary
ConstructorsConstructorDescriptionAbstractBatchedColumnProcessor
(int rowsPerBatch) Constructs a batched column processor configured to invoke thebatchesProcessed
method after a given number of rows has been processed. -
Method Summary
Modifier and TypeMethodDescriptionabstract void
batchProcessed
(int rowsInThisBatch) Callback to the user, where the lists with values parsed for all columns can be accessed using the methodsColumnReader.getColumnValuesAsList()
,ColumnReader.getColumnValuesAsMapOfIndexes()
andColumnReader.getColumnValuesAsMapOfNames()
.int
Returns the number of batches already processedgetColumn
(int columnIndex) Returns the values of a given column.Returns the values of a given column.Returns the values processed for each columnReturns a map of column indexes and their respective list of values parsed from the input.Returns a map of column names and their respective list of values parsed from the input.final String[]
Returns the column headers.int
Returns the number of rows processed in each batchvoid
processEnded
(T context) This method will by invoked by the parser once, after the parsing process stopped and all resources were closed.void
processStarted
(T context) This method will by invoked by the parser once, when it is ready to start processing the input.final void
Fills a given map associating each column index to its list of valuesfinal void
Fills a given map associating each column name to its list o valuesvoid
rowProcessed
(String[] row, T context) Invoked by the parser after all values of a valid record have been processed.
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Field Details
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splitter
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rowsPerBatch
private final int rowsPerBatch -
batchCount
private int batchCount -
batchesProcessed
private int batchesProcessed
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Constructor Details
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AbstractBatchedColumnProcessor
public AbstractBatchedColumnProcessor(int rowsPerBatch) Constructs a batched column processor configured to invoke thebatchesProcessed
method after a given number of rows has been processed.- Parameters:
rowsPerBatch
- the number of rows to process in each batch.
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Method Details
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processStarted
Description copied from interface:Processor
This method will by invoked by the parser once, when it is ready to start processing the input.- Specified by:
processStarted
in interfaceProcessor<T extends Context>
- Parameters:
context
- A contextual object with information and controls over the current state of the parsing process
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rowProcessed
Description copied from interface:Processor
Invoked by the parser after all values of a valid record have been processed.- Specified by:
rowProcessed
in interfaceProcessor<T extends Context>
- Parameters:
row
- the data extracted by the parser for an individual record. Note that:- it will never by null.
- it will never be empty unless explicitly configured using
CommonSettings.setSkipEmptyLines(boolean)
- it won't contain lines identified by the parser as comments. To disable comment processing set
Format.setComment(char)
to '\0'
context
- A contextual object with information and controls over the current state of the parsing process
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processEnded
Description copied from interface:Processor
This method will by invoked by the parser once, after the parsing process stopped and all resources were closed.It will always be called by the parser: in case of errors, if the end of the input us reached, or if the user stopped the process manually using
Context.stop()
.- Specified by:
processEnded
in interfaceProcessor<T extends Context>
- Parameters:
context
- A contextual object with information and controls over the state of the parsing process
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getHeaders
Description copied from interface:ColumnReader
Returns the column headers. This can be either the headers defined inCommonSettings.getHeaders()
or the headers parsed in the input whenCommonSettings.getHeaders()
equals totrue
- Specified by:
getHeaders
in interfaceColumnReader<T extends Context>
- Returns:
- the headers of all column parsed.
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getColumnValuesAsList
Description copied from interface:ColumnReader
Returns the values processed for each column- Specified by:
getColumnValuesAsList
in interfaceColumnReader<T extends Context>
- Returns:
- a list of lists. The stored lists correspond to the position of the column processed from the input; Each list contains the corresponding values parsed for a column, across multiple rows.
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putColumnValuesInMapOfNames
Description copied from interface:ColumnReader
Fills a given map associating each column name to its list o values- Specified by:
putColumnValuesInMapOfNames
in interfaceColumnReader<T extends Context>
- Parameters:
map
- the map to hold the values of each column
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putColumnValuesInMapOfIndexes
Description copied from interface:ColumnReader
Fills a given map associating each column index to its list of values- Specified by:
putColumnValuesInMapOfIndexes
in interfaceColumnReader<T extends Context>
- Parameters:
map
- the map to hold the values of each column
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getColumnValuesAsMapOfNames
Description copied from interface:ColumnReader
Returns a map of column names and their respective list of values parsed from the input.- Specified by:
getColumnValuesAsMapOfNames
in interfaceColumnReader<T extends Context>
- Returns:
- a map of column names and their respective list of values.
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getColumnValuesAsMapOfIndexes
Description copied from interface:ColumnReader
Returns a map of column indexes and their respective list of values parsed from the input.- Specified by:
getColumnValuesAsMapOfIndexes
in interfaceColumnReader<T extends Context>
- Returns:
- a map of column indexes and their respective list of values.
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getColumn
Description copied from interface:ColumnReader
Returns the values of a given column.- Specified by:
getColumn
in interfaceColumnReader<T extends Context>
- Parameters:
columnName
- the name of the column in the input.- Returns:
- a list with all data stored in the given column
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getColumn
Description copied from interface:ColumnReader
Returns the values of a given column.- Specified by:
getColumn
in interfaceColumnReader<T extends Context>
- Parameters:
columnIndex
- the position of the column in the input (0-based).- Returns:
- a list with all data stored in the given column
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getRowsPerBatch
public int getRowsPerBatch()Description copied from interface:BatchedColumnReader
Returns the number of rows processed in each batch- Specified by:
getRowsPerBatch
in interfaceBatchedColumnReader<T extends Context>
- Returns:
- the number of rows per batch
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getBatchesProcessed
public int getBatchesProcessed()Description copied from interface:BatchedColumnReader
Returns the number of batches already processed- Specified by:
getBatchesProcessed
in interfaceBatchedColumnReader<T extends Context>
- Returns:
- the number of batches already processed
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batchProcessed
public abstract void batchProcessed(int rowsInThisBatch) Description copied from interface:BatchedColumnReader
Callback to the user, where the lists with values parsed for all columns can be accessed using the methodsColumnReader.getColumnValuesAsList()
,ColumnReader.getColumnValuesAsMapOfIndexes()
andColumnReader.getColumnValuesAsMapOfNames()
.- Specified by:
batchProcessed
in interfaceBatchedColumnReader<T extends Context>
- Parameters:
rowsInThisBatch
- the number of rows processed in the current batch. This corresponds to the number of elements of each list of each column.
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