### Question:
ScalarOperandNode extends OperandNode { @Override public String toString() { return value; } ScalarOperandNode(DataType dataType, String value); String getValue(); @Override String toString();  }### Answer:
@Test public void testToString() { ScalarOperandNode scalarOperandNode = new ScalarOperandNode(DataType.VARCHAR, "abc"); assertSame(DataType.VARCHAR, scalarOperandNode.getDataType()); assertEquals("abc", scalarOperandNode.toString()); }