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/*******************************************************************************
* Copyright 2014 uniVocity Software Pty Ltd
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
******************************************************************************/
package com.univocity.parsers.common.processor;
/**
* A common interface for {@link RowProcessor}s that collect the values parsed from each column in a row and store values of columns in batches.
* Use implementations of this interface implementation in favor of {@link ColumnReaderProcessor} when processing large inputs to avoid running out of memory.
*
* During the execution of the process, the {@link #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 {@link #getColumnValuesAsList()},
* {@link #getColumnValuesAsMapOfIndexes()} and {@link #getColumnValuesAsMapOfNames()}.
* After {@link #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 BatchedColumnProcessor
* @see BatchedObjectColumnProcessor
* @see RowProcessor
*
* @author uniVocity Software Pty Ltd - [email protected]
*
* @param the type of the data stored by the columns.
*/
interface BatchedColumnReaderProcessor extends ColumnReaderProcessor {
/**
* Returns the number of rows processed in each batch
* @return the number of rows per batch
*/
public int getRowsPerBatch();
/**
* Returns the number of batches already processed
* @return the number of batches already processed
*/
public int getBatchesProcessed();
/**
* Callback to the user, where the lists with values parsed for all columns can be accessed using the methods {@link #getColumnValuesAsList()},
* {@link #getColumnValuesAsMapOfIndexes()} and {@link #getColumnValuesAsMapOfNames()}.
* @param rowsInThisBatch the number of rows processed in the current batch. This corresponds to the number of elements of each list of each column.
*/
public void batchProcessed(int rowsInThisBatch);
}