From: Javen O'Neal Date: Mon, 28 Dec 2015 13:44:08 +0000 (+0000) Subject: add convenience methods for writing and reading back XSSFWorkbooks X-Git-Tag: REL_3_14_FINAL~162 X-Git-Url: https://source.dussan.org/?a=commitdiff_plain;h=212121c53a98be93e21f06b7eae521e8864d7b28;p=poi.git add convenience methods for writing and reading back XSSFWorkbooks git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1721920 13f79535-47bb-0310-9956-ffa450edef68 --- diff --git a/src/ooxml/testcases/org/apache/poi/xssf/XSSFTestDataSamples.java b/src/ooxml/testcases/org/apache/poi/xssf/XSSFTestDataSamples.java index 61c93009d1..68188cb220 100644 --- a/src/ooxml/testcases/org/apache/poi/xssf/XSSFTestDataSamples.java +++ b/src/ooxml/testcases/org/apache/poi/xssf/XSSFTestDataSamples.java @@ -24,11 +24,12 @@ import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; +import java.io.OutputStream; import org.apache.poi.hssf.HSSFTestDataSamples; -import org.apache.poi.hssf.usermodel.HSSFWorkbook; import org.apache.poi.openxml4j.opc.OPCPackage; import org.apache.poi.ss.usermodel.Workbook; +import org.apache.poi.util.TempFile; import org.apache.poi.xssf.usermodel.XSSFWorkbook; /** @@ -62,63 +63,227 @@ public class XSSFTestDataSamples { throw new RuntimeException(e); } } + + /** + * Write out workbook wb to {@link #TEST_OUTPUT_DIR}/testName.xlsx + * (or create a temporary file if TEST_OUTPUT_DIR is not defined). + * + * @param wb the workbook to write + * @param testName a fragment of the filename + * @return the location where the workbook was saved + * @throws IOException + */ + public static File writeOut(R wb, String testName) throws IOException { + final String testOutputDir = System.getProperty(TEST_OUTPUT_DIR); + final File file; + if (testOutputDir != null) { + file = new File(testOutputDir, testName + ".xlsx"); + } + else { + file = TempFile.createTempFile(testName, ".xlsx"); + } + if (file.exists()) { + file.delete(); + } + final OutputStream out = new FileOutputStream(file); + try { + wb.write(out); + } finally { + out.close(); + } + return file; + } + + /** + * Write out workbook wb to a memory buffer + * + * @param wb the workbook to write + * @return the memory buffer + * @throws IOException + */ + public static ByteArrayOutputStream writeOut(R wb) throws IOException { + ByteArrayOutputStream out = new ByteArrayOutputStream(8192); + wb.write(out); + return out; + } + + /** + * Write out the workbook then closes the workbook. + * This should be used when there is insufficient memory to have + * both workbooks open. + * + * Make sure there are no references to any objects in the workbook + * so that garbage collection may free the workbook. + * + * After calling this method, null the reference to wb, + * then call {@link #readBack(File)} or {@link #readBackAndDelete(File)} to re-read the file. + * + * Alternatively, use {@link #writeOutAndClose(Workbook)} to use a ByteArrayOutputStream/ByteArrayInputStream + * to avoid creating a temporary file. However, this may complicate the calling + * code to avoid having the workbook, BAOS, and BAIS open at the same time. + * + * @param wb + * @param testName file name to be used to write to a file. This file will be cleaned up by a call to readBack(String) + * @return workbook location + * @throws RuntimeException if {@link #TEST_OUTPUT_DIR} System property is not set + */ + public static File writeOutAndClose(R wb, String testName) { + try { + File file = writeOut(wb, testName); + // Do not close the workbook if there was a problem writing the workbook + wb.close(); + return file; + } + catch (final IOException e) { + throw new RuntimeException(e); + } + } + + + /** + * Write out workbook wb to a memory buffer, + * then close the workbook + * + * @param wb the workbook to write + * @return the memory buffer + * @throws IOException + */ + public static ByteArrayOutputStream writeOutAndClose(R wb) { + try { + ByteArrayOutputStream out = writeOut(wb); + // Do not close the workbook if there was a problem writing the workbook + wb.close(); + return out; + } + catch (final IOException e) { + throw new RuntimeException(e); + } + } + + /** + * Read back a workbook that was written out to a file with + * {@link #writeOut(Workbook, String))} or {@link #writeOutAndClose(Workbook, String)}. + * Deletes the file after reading back the file. + * Does not delete the file if an exception is raised. + * + * @param file the workbook file to read and delete + * @return the read back workbook + * @throws IOException + */ + public static XSSFWorkbook readBackAndDelete(File file) throws IOException { + XSSFWorkbook wb = readBack(file); + // do not delete the file if there's an error--might be helpful for debugging + file.delete(); + return wb; + } + + /** + * Read back a workbook that was written out to a file with + * {@link #writeOut(Workbook, String)} or {@link #writeOutAndClose(Workbook, String)}. + * + * @param file the workbook file to read + * @return the read back workbook + * @throws IOException + */ + public static XSSFWorkbook readBack(File file) throws IOException { + InputStream in = new FileInputStream(file); + try { + return new XSSFWorkbook(in); + } + finally { + in.close(); + } + } + + /** + * Read back a workbook that was written out to a memory buffer with + * {@link #writeOut(Workbook)} or {@link #writeOutAndClose(Workbook)}. + * + * @param file the workbook file to read + * @return the read back workbook + * @throws IOException + */ + public static XSSFWorkbook readBack(ByteArrayOutputStream out) throws IOException { + InputStream is = new ByteArrayInputStream(out.toByteArray()); + out.close(); + try { + return new XSSFWorkbook(is); + } + finally { + is.close(); + } + } + + /** + * Write out and read back using a memory buffer to avoid disk I/O. + * If there is not enough memory to have two workbooks open at the same time, + * consider using: + * + * Workbook wb = new XSSFWorkbook(); + * String testName = "example"; + * + * + * File file = writeOutAndClose(wb, testName); + * // clear all references that would prevent the workbook from getting garbage collected + * wb = null; + * Workbook wbBack = readBackAndDelete(file); + * + * + * @param wb the workbook to write out + * @return the read back workbook + */ public static R writeOutAndReadBack(R wb) { Workbook result; try { - ByteArrayOutputStream baos = new ByteArrayOutputStream(8192); - wb.write(baos); - InputStream is = new ByteArrayInputStream(baos.toByteArray()); - if (wb instanceof HSSFWorkbook) { - result = new HSSFWorkbook(is); - } else if (wb instanceof XSSFWorkbook) { - result = new XSSFWorkbook(is); - } else { - throw new RuntimeException("Unexpected workbook type (" - + wb.getClass().getName() + ")"); - } + result = readBack(writeOut(wb)); + } catch (IOException e) { + throw new RuntimeException(e); + } + @SuppressWarnings("unchecked") + R r = (R) result; + return r; + } + + /** + * Write out, close, and read back the workbook using a memory buffer to avoid disk I/O. + * + * @param wb the workbook to write out and close + * @return the read back workbook + */ + public static R writeOutCloseAndReadBack(R wb) { + Workbook result; + try { + result = readBack(writeOutAndClose(wb)); } catch (IOException e) { throw new RuntimeException(e); } @SuppressWarnings("unchecked") R r = (R) result; return r; + } /** * Writes the Workbook either into a file or into a byte array, depending on presence of * the system property {@value #TEST_OUTPUT_DIR}, and reads it in a new instance of the Workbook back. + * If TEST_OUTPUT_DIR is set, the file will NOT be deleted at the end of this function. * @param wb workbook to write * @param testName file name to be used if writing into a file. The old file with the same name will be overridden. * @return new instance read from the stream written by the wb parameter. */ + public static R writeOutAndReadBack(R wb, String testName) { - XSSFWorkbook result = null; - if (System.getProperty(TEST_OUTPUT_DIR) != null) { + if (System.getProperty(TEST_OUTPUT_DIR) == null) { + return writeOutAndReadBack(wb); + } else { try { - File file = new File(System.getProperty(TEST_OUTPUT_DIR), testName + ".xlsx"); - if (file.exists()) { - file.delete(); - } - FileOutputStream out = new FileOutputStream(file); - try { - wb.write(out); - } finally { - out.close(); - } - FileInputStream in = new FileInputStream(file); - try { - result = new XSSFWorkbook(in); - } finally { - in.close(); - } + Workbook result = readBack(writeOut(wb, testName)); + @SuppressWarnings("unchecked") + R r = (R) result; + return r; } catch (IOException e) { throw new RuntimeException(e); } - } else { - return writeOutAndReadBack(wb); } - @SuppressWarnings("unchecked") - R r = (R) result; - return r; } }