private void dropFile(String fileName, int lines) throws IOException {
		PrintWriter writer = new PrintWriter(sourceDirName + "/" + fileName, "UTF-8");
		for (int i = 1; i <= lines; i++) {
			writer.write("foo");
			if (i < lines) {
				writer.write("\n");
			}
		}
		writer.close();
	}
@author David Turanski
@author Gunnar Hillert
@author Gary Russell
spring-xd-dirt/src/test/java/org/springframework/xd/dirt/stream/FileSourceModuleTests.java