org.apache.poi.xssf.streaming.examples.HybridStreaming Maven / Gradle / Ivy
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package org.apache.poi.xssf.streaming.examples;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import org.apache.poi.xssf.eventusermodel.ReadOnlySharedStringsTable;
import org.apache.poi.xssf.eventusermodel.XSSFSheetXMLHandler;
import org.apache.poi.xssf.eventusermodel.XSSFSheetXMLHandler.SheetContentsHandler;
import org.apache.poi.xssf.usermodel.XSSFComment;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;
import org.openxmlformats.schemas.spreadsheetml.x2006.main.CTSheet;
import org.xml.sax.SAXException;
/**
* This demonstrates how a hybrid approach to workbook read can be taken, using
* a mix of traditional XSSF and streaming one particular worksheet (perhaps one
* which is too big for the ordinary DOM parse).
*/
public class HybridStreaming {
private static final String SHEET_TO_STREAM = "large sheet";
public static void main(String[] args) throws IOException, SAXException {
InputStream sourceBytes = new FileInputStream("/path/too/workbook.xlsx");
XSSFWorkbook workbook = new XSSFWorkbook(sourceBytes) {
/** Avoid DOM parse of large sheet */
public void parseSheet(java.util.Map shIdMap, CTSheet ctSheet) {
if (!SHEET_TO_STREAM.equals(ctSheet.getName())) {
super.parseSheet(shIdMap, ctSheet);
}
};
};
// Having avoided a DOM-based parse of the sheet, we can stream it instead.
ReadOnlySharedStringsTable strings = new ReadOnlySharedStringsTable(workbook.getPackage());
new XSSFSheetXMLHandler(workbook.getStylesSource(), strings, createSheetContentsHandler(), false);
workbook.close();
}
private static SheetContentsHandler createSheetContentsHandler() {
return new SheetContentsHandler() {
public void startRow(int rowNum) {
}
public void headerFooter(String text, boolean isHeader, String tagName) {
}
public void endRow(int rowNum) {
}
public void cell(String cellReference, String formattedValue, XSSFComment comment) {
}
};
}
}