### Question:
StringField implements FieldType<String> { @Override public boolean hasDefaultValue() { return hasDefaultValue; } StringField(final Types type);  StringField(final String defaultValue, final Types type);  StringField(final Types type, final String length);  StringField(final Types type, final String length, final String defaultValue); @Override Types getType(); long getLength(); @Override String getDefaultValue(); @Override boolean hasDefaultValue(); @Override String convert(Object objValue); @Override JSONObject toJson();  }### Answer:
@Test public void testHasDefaultValue() throws OperationException { System.out.println("hasDefaultValue"); StringField instance; instance = new StringField(Types.STRING); assertFalse(instance.hasDefaultValue()); instance = new StringField(Types.STRING, "100"); assertFalse(instance.hasDefaultValue()); instance = new StringField("something", Types.STRING); assertTrue(instance.hasDefaultValue()); instance = new StringField(Types.STRING, "100", "something"); assertTrue(instance.hasDefaultValue()); }