log4j/src/ooxml/testcases/org/apache/poi/openxml4j/opc/compliance/TestOPCComplianceCoreProperties.java - poi - Git at Google

 /* ====================================================================
    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.poi.openxml4j.opc.compliance;

 import static org.apache.poi.openxml4j.OpenXML4JTestDataSamples.openComplianceSampleStream;
 import static org.apache.poi.openxml4j.OpenXML4JTestDataSamples.openSampleStream;
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;

 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
 import java.io.FileOutputStream;
 import java.io.IOException;
 import java.io.InputStream;
 import java.net.URI;
 import java.net.URISyntaxException;

 import org.apache.poi.POIDataSamples;
 import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
 import org.apache.poi.openxml4j.exceptions.InvalidOperationException;
 import org.apache.poi.openxml4j.opc.ContentTypes;
 import org.apache.poi.openxml4j.opc.OPCPackage;
 import org.apache.poi.openxml4j.opc.PackageRelationshipTypes;
 import org.apache.poi.openxml4j.opc.PackagingURIHelper;
 import org.apache.poi.openxml4j.opc.TargetMode;
 import org.apache.poi.util.IOUtils;
 import org.apache.poi.util.TempFile;
 import org.junit.jupiter.api.Test;

 /**
  * Test core properties Open Packaging Convention compliance.
  *
  * M4.1: The format designer shall specify and the format producer shall create
  * at most one core properties relationship for a package. A format consumer
  * shall consider more than one core properties relationship for a package to be
  * an error. If present, the relationship shall target the Core Properties part.
  * (POI relaxes this on reading, as Office sometimes breaks this)
  *
  * M4.2: The format designer shall not specify and the format producer shall not
  * create Core Properties that use the Markup Compatibility namespace as defined
  * in Annex F, "Standard Namespaces and Content Types". A format consumer shall
  * consider the use of the Markup Compatibility namespace to be an error.
  *
  * M4.3: Producers shall not create a document element that contains refinements
  * to the Dublin Core elements, except for the two specified in the schema:
  * <dcterms:created> and <dcterms:modified> Consumers shall consider a document
  * element that violates this constraint to be an error.
  *
  * M4.4: Producers shall not create a document element that contains the
  * xml:lang attribute. Consumers shall consider a document element that violates
  * this constraint to be an error.
  *
  * M4.5: Producers shall not create a document element that contains the
  * xsi:type attribute, except for a <dcterms:created> or <dcterms:modified>
  * element where the xsi:type attribute shall be present and shall hold the
  * value dcterms:W3CDTF, where dcterms is the namespace prefix of the Dublin
  * Core namespace. Consumers shall consider a document element that violates
  * this constraint to be an error.
  */
 public final class TestOPCComplianceCoreProperties {

     @Test
     void testCorePropertiesPart() throws IOException {
         try (InputStream is = openComplianceSampleStream("OPCCompliance_CoreProperties_OnlyOneCorePropertiesPart.docx")) {
             assertDoesNotThrow(() -> OPCPackage.open(is).close());
         }
     }

     private static String extractInvalidFormatMessage(String sampleNameSuffix) throws IOException {
         try (InputStream is = openComplianceSampleStream("OPCCompliance_CoreProperties_" + sampleNameSuffix)) {
             InvalidFormatException e = assertThrows(InvalidFormatException.class,
                 () -> OPCPackage.open(is).revert(), "expected OPC compliance exception was not thrown");
             return e.getMessage();
         }
     }

     /**
      * Test M4.1 rule.
      */
     @Test
     void testOnlyOneCorePropertiesPart() throws Exception {
        // We have relaxed this check, so we can read the file anyway
         assertDoesNotThrow(() -> {
             try (InputStream is = openSampleStream("OPCCompliance_CoreProperties_OnlyOneCorePropertiesPartFAIL.docx");
                  OPCPackage pkg = OPCPackage.open(is)) {
                 assertNotNull(pkg);
             }
         }, "M4.1 should be being relaxed");

        // We will use the first core properties, and ignore the others

       try (InputStream is = openSampleStream("MultipleCoreProperties.docx");
            OPCPackage pkg = OPCPackage.open(is)) {

           // We can see 2 by type
           assertEquals(2, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
           // But only the first one by relationship
           assertEquals(1, pkg.getPartsByRelationshipType(PackageRelationshipTypes.CORE_PROPERTIES).size());
           // It should be core.xml not the older core1.xml
           assertEquals(
                   "/docProps/core.xml",
                   pkg.getPartsByRelationshipType(PackageRelationshipTypes.CORE_PROPERTIES).get(0).getPartName().toString()
           );
       }
     }

     private static URI createURI(String text) {
         try {
             return new URI(text);
         } catch (URISyntaxException e) {
             throw new RuntimeException(e);
         }
     }

     /**
      * Test M4.1 rule.
      */
     @Test
     void testOnlyOneCorePropertiesPart_AddRelationship() throws IOException, InvalidFormatException {
         try (InputStream is = openComplianceSampleStream("OPCCompliance_CoreProperties_OnlyOneCorePropertiesPart.docx")) {
             OPCPackage pkg = OPCPackage.open(is);
             URI partUri = createURI("/docProps/core2.xml");
             InvalidOperationException e = assertThrows(InvalidOperationException.class, () ->
                     pkg.addRelationship(PackagingURIHelper.createPartName(partUri), TargetMode.INTERNAL, PackageRelationshipTypes.CORE_PROPERTIES),
                 "expected OPC compliance exception was not thrown"
             );
             assertEquals("OPC Compliance error [M4.1]: can't add another core properties part ! Use the built-in package method instead.", e.getMessage());
             pkg.revert();
         }
     }

     /**
      * Test M4.1 rule.
      */
     @Test
     void testOnlyOneCorePropertiesPart_AddPart() throws InvalidFormatException, IOException {
         String sampleFileName = "OPCCompliance_CoreProperties_OnlyOneCorePropertiesPart.docx";
         try (OPCPackage pkg = OPCPackage.open(POIDataSamples.getOpenXML4JInstance().getFile(sampleFileName).getPath())) {

             URI partUri = createURI("/docProps/core2.xml");
             InvalidOperationException e = assertThrows(InvalidOperationException.class, () ->
                     pkg.createPart(PackagingURIHelper.createPartName(partUri), ContentTypes.CORE_PROPERTIES_PART),
                 "expected OPC compliance exception was not thrown");
             assertEquals("OPC Compliance error [M4.1]: you try to add more than one core properties relationship in the package !", e.getMessage());
             pkg.revert();
         }
     }

     /**
      * Test M4.2 rule.
      */
     @Test
     void testDoNotUseCompatibilityMarkup() throws IOException {
         String msg = extractInvalidFormatMessage("DoNotUseCompatibilityMarkupFAIL.docx");
         assertEquals("OPC Compliance error [M4.2]: A format consumer shall consider the use of the Markup Compatibility namespace to be an error.", msg);
     }

     /**
      * Test M4.3 rule.
      */
     @Test
     void testDCTermsNamespaceLimitedUse() throws IOException {
         String msg = extractInvalidFormatMessage("DCTermsNamespaceLimitedUseFAIL.docx");
         assertEquals("OPC Compliance error [M4.3]: Producers shall not create a document element that contains refinements to the Dublin Core elements, except for the two specified in the schema: <dcterms:created> and <dcterms:modified> Consumers shall consider a document element that violates this constraint to be an error.", msg);
     }

     /**
      * Test M4.4 rule.
      */
     @Test
     void testUnauthorizedXMLLangAttribute() throws IOException {
         String msg = extractInvalidFormatMessage("UnauthorizedXMLLangAttributeFAIL.docx");
         assertEquals("OPC Compliance error [M4.4]: Producers shall not create a document element that contains the xml:lang attribute. Consumers shall consider a document element that violates this constraint to be an error.", msg);
     }

     /**
      * Test M4.5 rule.
      */
     @Test
     void testLimitedXSITypeAttribute_NotPresent() throws IOException {
         String msg = extractInvalidFormatMessage("LimitedXSITypeAttribute_NotPresentFAIL.docx");
         assertEquals("The element 'created' must have the 'xsi:type' attribute present !", msg);
     }

     /**
      * Test M4.5 rule.
      */
     @Test
     void testLimitedXSITypeAttribute_PresentWithUnauthorizedValue() throws IOException {
         String msg = extractInvalidFormatMessage("LimitedXSITypeAttribute_PresentWithUnauthorizedValueFAIL.docx");
         assertEquals("The element 'modified' must have the 'xsi:type' attribute with the value 'dcterms:W3CDTF', but had 'W3CDTF' !", msg);
     }

     /**
      * Document with no core properties - testing at the OPC level,
      *  saving into a new stream
      */
     @Test
     void testNoCoreProperties_saveNew() throws Exception {
         String sampleFileName = "OPCCompliance_NoCoreProperties.xlsx";
         ByteArrayOutputStream baos = new ByteArrayOutputStream();

         try (OPCPackage pkg = OPCPackage.open(POIDataSamples.getOpenXML4JInstance().getFile(sampleFileName).getPath())) {
             // Verify it has empty properties
             assertEquals(0, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
             assertNotNull(pkg.getPackageProperties());
             assertNotNull(pkg.getPackageProperties().getLanguageProperty());
             assertFalse(pkg.getPackageProperties().getLanguageProperty().isPresent());

             // Save and re-load
             pkg.save(baos);
             pkg.revert();
         }

         try (OPCPackage pkg = OPCPackage.open(new ByteArrayInputStream(baos.toByteArray()))) {
             // An Empty Properties part has been added in the save/load
             assertEquals(1, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
             assertNotNull(pkg.getPackageProperties());
             assertNotNull(pkg.getPackageProperties().getLanguageProperty());
             assertFalse(pkg.getPackageProperties().getLanguageProperty().isPresent());
         }

         // Open a new copy of it
         try (OPCPackage pkg = OPCPackage.open(POIDataSamples.getOpenXML4JInstance().getFile(sampleFileName).getPath())) {
             // Save and re-load, without having touched the properties yet
             baos.reset();
             pkg.save(baos);
             pkg.revert();
         }

         try (OPCPackage pkg = OPCPackage.open(new ByteArrayInputStream(baos.toByteArray()))) {
             // Check that this too added empty properties without error
             assertEquals(1, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
             assertNotNull(pkg.getPackageProperties());
             assertNotNull(pkg.getPackageProperties().getLanguageProperty());
             assertFalse(pkg.getPackageProperties().getLanguageProperty().isPresent());
         }
     }

     /**
      * Document with no core properties - testing at the OPC level,
      *  from a temp-file, saving in-place
      */
     @Test
     void testNoCoreProperties_saveInPlace() throws Exception {
         String sampleFileName = "OPCCompliance_NoCoreProperties.xlsx";

         // Copy this into a temp file, so we can play with it
         File tmp = TempFile.createTempFile("poi-test", ".opc");
         try (FileOutputStream out = new FileOutputStream(tmp);
             InputStream in = POIDataSamples.getOpenXML4JInstance().openResourceAsStream(sampleFileName)) {
             IOUtils.copy(in, out);
         }

         // Open it from that temp file
         try (OPCPackage pkg = OPCPackage.open(tmp)) {

             // Empty properties
             assertEquals(0, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
             assertNotNull(pkg.getPackageProperties());
             assertNotNull(pkg.getPackageProperties().getLanguageProperty());
             assertFalse(pkg.getPackageProperties().getLanguageProperty().isPresent());

             // Save and close
         }

         // Re-open and check
         try (OPCPackage pkg = OPCPackage.open(tmp)) {
             // An Empty Properties part has been added in the save/load
             assertEquals(1, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
             assertNotNull(pkg.getPackageProperties());
             assertNotNull(pkg.getPackageProperties().getLanguageProperty());
             assertFalse(pkg.getPackageProperties().getLanguageProperty().isPresent());

             // Finish and tidy
             pkg.revert();
         }
         assertTrue(tmp.delete());
     }
 }
	/* ====================================================================
	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.poi.openxml4j.opc.compliance;

	import static org.apache.poi.openxml4j.OpenXML4JTestDataSamples.openComplianceSampleStream;
	import static org.apache.poi.openxml4j.OpenXML4JTestDataSamples.openSampleStream;
	import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
	import static org.junit.jupiter.api.Assertions.assertEquals;
	import static org.junit.jupiter.api.Assertions.assertFalse;
	import static org.junit.jupiter.api.Assertions.assertNotNull;
	import static org.junit.jupiter.api.Assertions.assertThrows;
	import static org.junit.jupiter.api.Assertions.assertTrue;

	import java.io.ByteArrayInputStream;
	import java.io.ByteArrayOutputStream;
	import java.io.File;
	import java.io.FileOutputStream;
	import java.io.IOException;
	import java.io.InputStream;
	import java.net.URI;
	import java.net.URISyntaxException;

	import org.apache.poi.POIDataSamples;
	import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
	import org.apache.poi.openxml4j.exceptions.InvalidOperationException;
	import org.apache.poi.openxml4j.opc.ContentTypes;
	import org.apache.poi.openxml4j.opc.OPCPackage;
	import org.apache.poi.openxml4j.opc.PackageRelationshipTypes;
	import org.apache.poi.openxml4j.opc.PackagingURIHelper;
	import org.apache.poi.openxml4j.opc.TargetMode;
	import org.apache.poi.util.IOUtils;
	import org.apache.poi.util.TempFile;
	import org.junit.jupiter.api.Test;

	/**
	* Test core properties Open Packaging Convention compliance.
	*
	* M4.1: The format designer shall specify and the format producer shall create
	* at most one core properties relationship for a package. A format consumer
	* shall consider more than one core properties relationship for a package to be
	* an error. If present, the relationship shall target the Core Properties part.
	* (POI relaxes this on reading, as Office sometimes breaks this)
	*
	* M4.2: The format designer shall not specify and the format producer shall not
	* create Core Properties that use the Markup Compatibility namespace as defined
	* in Annex F, "Standard Namespaces and Content Types". A format consumer shall
	* consider the use of the Markup Compatibility namespace to be an error.
	*
	* M4.3: Producers shall not create a document element that contains refinements
	* to the Dublin Core elements, except for the two specified in the schema:
	* <dcterms:created> and <dcterms:modified> Consumers shall consider a document
	* element that violates this constraint to be an error.
	*
	* M4.4: Producers shall not create a document element that contains the
	* xml:lang attribute. Consumers shall consider a document element that violates
	* this constraint to be an error.
	*
	* M4.5: Producers shall not create a document element that contains the
	* xsi:type attribute, except for a <dcterms:created> or <dcterms:modified>
	* element where the xsi:type attribute shall be present and shall hold the
	* value dcterms:W3CDTF, where dcterms is the namespace prefix of the Dublin
	* Core namespace. Consumers shall consider a document element that violates
	* this constraint to be an error.
	*/
	public final class TestOPCComplianceCoreProperties {

	@Test
	void testCorePropertiesPart() throws IOException {
	try (InputStream is = openComplianceSampleStream("OPCCompliance_CoreProperties_OnlyOneCorePropertiesPart.docx")) {
	assertDoesNotThrow(() -> OPCPackage.open(is).close());
	}
	}

	private static String extractInvalidFormatMessage(String sampleNameSuffix) throws IOException {
	try (InputStream is = openComplianceSampleStream("OPCCompliance_CoreProperties_" + sampleNameSuffix)) {
	InvalidFormatException e = assertThrows(InvalidFormatException.class,
	() -> OPCPackage.open(is).revert(), "expected OPC compliance exception was not thrown");
	return e.getMessage();
	}
	}

	/**
	* Test M4.1 rule.
	*/
	@Test
	void testOnlyOneCorePropertiesPart() throws Exception {
	// We have relaxed this check, so we can read the file anyway
	assertDoesNotThrow(() -> {
	try (InputStream is = openSampleStream("OPCCompliance_CoreProperties_OnlyOneCorePropertiesPartFAIL.docx");
	OPCPackage pkg = OPCPackage.open(is)) {
	assertNotNull(pkg);
	}
	}, "M4.1 should be being relaxed");

	// We will use the first core properties, and ignore the others

	try (InputStream is = openSampleStream("MultipleCoreProperties.docx");
	OPCPackage pkg = OPCPackage.open(is)) {

	// We can see 2 by type
	assertEquals(2, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
	// But only the first one by relationship
	assertEquals(1, pkg.getPartsByRelationshipType(PackageRelationshipTypes.CORE_PROPERTIES).size());
	// It should be core.xml not the older core1.xml
	assertEquals(
	"/docProps/core.xml",
	pkg.getPartsByRelationshipType(PackageRelationshipTypes.CORE_PROPERTIES).get(0).getPartName().toString()
	);
	}
	}

	private static URI createURI(String text) {
	try {
	return new URI(text);
	} catch (URISyntaxException e) {
	throw new RuntimeException(e);
	}
	}

	/**
	* Test M4.1 rule.
	*/
	@Test
	void testOnlyOneCorePropertiesPart_AddRelationship() throws IOException, InvalidFormatException {
	try (InputStream is = openComplianceSampleStream("OPCCompliance_CoreProperties_OnlyOneCorePropertiesPart.docx")) {
	OPCPackage pkg = OPCPackage.open(is);
	URI partUri = createURI("/docProps/core2.xml");
	InvalidOperationException e = assertThrows(InvalidOperationException.class, () ->
	pkg.addRelationship(PackagingURIHelper.createPartName(partUri), TargetMode.INTERNAL, PackageRelationshipTypes.CORE_PROPERTIES),
	"expected OPC compliance exception was not thrown"
	);
	assertEquals("OPC Compliance error [M4.1]: can't add another core properties part ! Use the built-in package method instead.", e.getMessage());
	pkg.revert();
	}
	}

	/**
	* Test M4.1 rule.
	*/
	@Test
	void testOnlyOneCorePropertiesPart_AddPart() throws InvalidFormatException, IOException {
	String sampleFileName = "OPCCompliance_CoreProperties_OnlyOneCorePropertiesPart.docx";
	try (OPCPackage pkg = OPCPackage.open(POIDataSamples.getOpenXML4JInstance().getFile(sampleFileName).getPath())) {

	URI partUri = createURI("/docProps/core2.xml");
	InvalidOperationException e = assertThrows(InvalidOperationException.class, () ->
	pkg.createPart(PackagingURIHelper.createPartName(partUri), ContentTypes.CORE_PROPERTIES_PART),
	"expected OPC compliance exception was not thrown");
	assertEquals("OPC Compliance error [M4.1]: you try to add more than one core properties relationship in the package !", e.getMessage());
	pkg.revert();
	}
	}

	/**
	* Test M4.2 rule.
	*/
	@Test
	void testDoNotUseCompatibilityMarkup() throws IOException {
	String msg = extractInvalidFormatMessage("DoNotUseCompatibilityMarkupFAIL.docx");
	assertEquals("OPC Compliance error [M4.2]: A format consumer shall consider the use of the Markup Compatibility namespace to be an error.", msg);
	}

	/**
	* Test M4.3 rule.
	*/
	@Test
	void testDCTermsNamespaceLimitedUse() throws IOException {
	String msg = extractInvalidFormatMessage("DCTermsNamespaceLimitedUseFAIL.docx");
	assertEquals("OPC Compliance error [M4.3]: Producers shall not create a document element that contains refinements to the Dublin Core elements, except for the two specified in the schema: <dcterms:created> and <dcterms:modified> Consumers shall consider a document element that violates this constraint to be an error.", msg);
	}

	/**
	* Test M4.4 rule.
	*/
	@Test
	void testUnauthorizedXMLLangAttribute() throws IOException {
	String msg = extractInvalidFormatMessage("UnauthorizedXMLLangAttributeFAIL.docx");
	assertEquals("OPC Compliance error [M4.4]: Producers shall not create a document element that contains the xml:lang attribute. Consumers shall consider a document element that violates this constraint to be an error.", msg);
	}

	/**
	* Test M4.5 rule.
	*/
	@Test
	void testLimitedXSITypeAttribute_NotPresent() throws IOException {
	String msg = extractInvalidFormatMessage("LimitedXSITypeAttribute_NotPresentFAIL.docx");
	assertEquals("The element 'created' must have the 'xsi:type' attribute present !", msg);
	}

	/**
	* Test M4.5 rule.
	*/
	@Test
	void testLimitedXSITypeAttribute_PresentWithUnauthorizedValue() throws IOException {
	String msg = extractInvalidFormatMessage("LimitedXSITypeAttribute_PresentWithUnauthorizedValueFAIL.docx");
	assertEquals("The element 'modified' must have the 'xsi:type' attribute with the value 'dcterms:W3CDTF', but had 'W3CDTF' !", msg);
	}

	/**
	* Document with no core properties - testing at the OPC level,
	* saving into a new stream
	*/
	@Test
	void testNoCoreProperties_saveNew() throws Exception {
	String sampleFileName = "OPCCompliance_NoCoreProperties.xlsx";
	ByteArrayOutputStream baos = new ByteArrayOutputStream();

	try (OPCPackage pkg = OPCPackage.open(POIDataSamples.getOpenXML4JInstance().getFile(sampleFileName).getPath())) {
	// Verify it has empty properties
	assertEquals(0, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
	assertNotNull(pkg.getPackageProperties());
	assertNotNull(pkg.getPackageProperties().getLanguageProperty());
	assertFalse(pkg.getPackageProperties().getLanguageProperty().isPresent());

	// Save and re-load
	pkg.save(baos);
	pkg.revert();
	}

	try (OPCPackage pkg = OPCPackage.open(new ByteArrayInputStream(baos.toByteArray()))) {
	// An Empty Properties part has been added in the save/load
	assertEquals(1, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
	assertNotNull(pkg.getPackageProperties());
	assertNotNull(pkg.getPackageProperties().getLanguageProperty());
	assertFalse(pkg.getPackageProperties().getLanguageProperty().isPresent());
	}

	// Open a new copy of it
	try (OPCPackage pkg = OPCPackage.open(POIDataSamples.getOpenXML4JInstance().getFile(sampleFileName).getPath())) {
	// Save and re-load, without having touched the properties yet
	baos.reset();
	pkg.save(baos);
	pkg.revert();
	}

	try (OPCPackage pkg = OPCPackage.open(new ByteArrayInputStream(baos.toByteArray()))) {
	// Check that this too added empty properties without error
	assertEquals(1, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
	assertNotNull(pkg.getPackageProperties());
	assertNotNull(pkg.getPackageProperties().getLanguageProperty());
	assertFalse(pkg.getPackageProperties().getLanguageProperty().isPresent());
	}
	}

	/**
	* Document with no core properties - testing at the OPC level,
	* from a temp-file, saving in-place
	*/
	@Test
	void testNoCoreProperties_saveInPlace() throws Exception {
	String sampleFileName = "OPCCompliance_NoCoreProperties.xlsx";

	// Copy this into a temp file, so we can play with it
	File tmp = TempFile.createTempFile("poi-test", ".opc");
	try (FileOutputStream out = new FileOutputStream(tmp);
	InputStream in = POIDataSamples.getOpenXML4JInstance().openResourceAsStream(sampleFileName)) {
	IOUtils.copy(in, out);
	}

	// Open it from that temp file
	try (OPCPackage pkg = OPCPackage.open(tmp)) {

	// Empty properties
	assertEquals(0, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
	assertNotNull(pkg.getPackageProperties());
	assertNotNull(pkg.getPackageProperties().getLanguageProperty());
	assertFalse(pkg.getPackageProperties().getLanguageProperty().isPresent());

	// Save and close
	}

	// Re-open and check
	try (OPCPackage pkg = OPCPackage.open(tmp)) {
	// An Empty Properties part has been added in the save/load
	assertEquals(1, pkg.getPartsByContentType(ContentTypes.CORE_PROPERTIES_PART).size());
	assertNotNull(pkg.getPackageProperties());
	assertNotNull(pkg.getPackageProperties().getLanguageProperty());
	assertFalse(pkg.getPackageProperties().getLanguageProperty().isPresent());

	// Finish and tidy
	pkg.revert();
	}
	assertTrue(tmp.delete());
	}
	}