org.apache.parquet.column.page.PageWriter Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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 org.apache.parquet.column.page;
import java.io.IOException;
import org.apache.parquet.bytes.BytesInput;
import org.apache.parquet.column.Encoding;
import org.apache.parquet.column.statistics.Statistics;
/**
* a writer for all the pages of a given column chunk
*/
public interface PageWriter {
/**
* writes a single page
* @param bytesInput the bytes for the page
* @param valueCount the number of values in that page
* @param statistics the statistics for that page
* @param rlEncoding repetition level encoding
* @param dlEncoding definition level encoding
* @param valuesEncoding values encoding
* @throws IOException if there is an exception while writing page data
* @deprecated will be removed in 2.0.0. This method does not support writing column indexes; Use
* {@link #writePage(BytesInput, int, int, Statistics, Encoding, Encoding, Encoding)} instead
*/
@Deprecated
void writePage(BytesInput bytesInput, int valueCount, Statistics> statistics, Encoding rlEncoding, Encoding dlEncoding, Encoding valuesEncoding) throws IOException;
/**
* writes a single page
* @param bytesInput the bytes for the page
* @param valueCount the number of values in that page
* @param rowCount the number of rows in that page
* @param statistics the statistics for that page
* @param rlEncoding repetition level encoding
* @param dlEncoding definition level encoding
* @param valuesEncoding values encoding
* @throws IOException
*/
void writePage(BytesInput bytesInput, int valueCount, int rowCount, Statistics> statistics, Encoding rlEncoding, Encoding dlEncoding, Encoding valuesEncoding) throws IOException;
/**
* writes a single page in the new format
* @param rowCount the number of rows in this page
* @param nullCount the number of null values (out of valueCount)
* @param valueCount the number of values in that page (there could be multiple values per row for repeated fields)
* @param repetitionLevels the repetition levels encoded in RLE without any size header
* @param definitionLevels the definition levels encoded in RLE without any size header
* @param dataEncoding the encoding for the data
* @param data the data encoded with dataEncoding
* @param statistics optional stats for this page
* @throws IOException if there is an exception while writing page data
*/
void writePageV2(
int rowCount, int nullCount, int valueCount,
BytesInput repetitionLevels, BytesInput definitionLevels,
Encoding dataEncoding,
BytesInput data,
Statistics> statistics) throws IOException;
/**
* @return the current size used in the memory buffer for that column chunk
*/
long getMemSize();
/**
* @return the allocated size for the buffer ( > getMemSize() )
*/
long allocatedSize();
/**
* writes a dictionary page
* @param dictionaryPage the dictionary page containing the dictionary data
* @throws IOException if there was an exception while writing
*/
void writeDictionaryPage(DictionaryPage dictionaryPage) throws IOException;
/**
* @param prefix a prefix header to add at every line
* @return a string presenting a summary of how memory is used
*/
String memUsageString(String prefix);
}