@Test public void withMetaData() { StringColumn stringColumn = StringColumn.builder(NAME).build(); IntColumn intColumn = IntColumn.builder(AGE).build(); DataFrame df = DataFrame.ofAll(stringColumn, intColumn); Map<String, String> metaData = LinkedHashMap.of("foo", "bar"); DataFrame withMetaData = df.withMetaData(metaData); assertEquals(metaData, withMetaData.getMetaData()); assertEquals(2, withMetaData.getColumnCount()); }