#vulnerable code 
                             @Test
	@Category(org.imixs.workflow.ItemCollection.class)
	public void testFileData() {
		ItemCollection itemColSource = new ItemCollection();

		// add a dummy file
		byte[] empty = { 0 };
		itemColSource.addFile(empty, "test1.txt", "application/xml");

		ItemCollection itemColTarget = new ItemCollection();

		itemColTarget.addFileData(itemColSource.getFileData("test1.txt"));

		FileData filedata = itemColTarget.getFileData("test1.txt");
		Assert.assertNotNull(filedata);
		Assert.assertEquals("test1.txt", filedata.getName());
		Assert.assertEquals("application/xml", filedata.getContentType());

		// test the byte content of itemColSource
		Map<String, List<Object>> conedFiles1 = itemColSource.getFiles();
		List<Object> fileContent1 = conedFiles1.get("test1.txt");
		byte[] file1Data1 = (byte[]) fileContent1.get(1);
		// we expect the new dummy array { 1, 2, 3 }
		Assert.assertArrayEquals(empty, file1Data1);

		// test the byte content of itemColTarget
		conedFiles1 = itemColTarget.getFiles();
		fileContent1 = conedFiles1.get("test1.txt");
		file1Data1 = (byte[]) fileContent1.get(1);
		// we expect the new dummy array { 1, 2, 3 }
		Assert.assertArrayEquals(empty, file1Data1);

	} 
                            #location 28 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                             @Test
	@Category(org.imixs.workflow.ItemCollection.class)
	public void testFileData() {
		ItemCollection itemColSource = new ItemCollection();

		// add a dummy file
		byte[] empty = { 0 };
		itemColSource.addFileData(new FileData( "test1.txt", empty,"application/xml",null));

		ItemCollection itemColTarget = new ItemCollection();

		itemColTarget.addFileData(itemColSource.getFileData("test1.txt"));

		FileData filedata = itemColTarget.getFileData("test1.txt");
		Assert.assertNotNull(filedata);
		Assert.assertEquals("test1.txt", filedata.getName());
		Assert.assertEquals("application/xml", filedata.getContentType());

		// test the byte content of itemColSource
		byte[] file1Data1 =itemColSource.getFileData("test1.txt").getContent();
		// we expect the new dummy array { 1, 2, 3 }
		Assert.assertArrayEquals(empty, file1Data1);

		// test the byte content of itemColTarget
		file1Data1 = itemColTarget.getFileData("test1.txt").getContent();
		// we expect the new dummy array { 1, 2, 3 }
		Assert.assertArrayEquals(empty, file1Data1);

	}