### Question:
TenantAndIdEmittableKey extends EmittableKey { public Text getIdField() { return fieldNames[ID_FIELD]; } TenantAndIdEmittableKey();  TenantAndIdEmittableKey(final String tenantIdFieldName, final String idFieldName); Text getTenantId(); void setTenantId(final Text id); Text getTenantIdField(); Text getId(); void setId(final Text id); Text getIdField(); @Override void readFields(DataInput data); @Override void write(DataOutput data); @Override String toString(); @Override BSONObject toBSON(); @Override int hashCode(); @Override boolean equals(Object obj); @Override int compareTo(EmittableKey other);  }### Answer:
@Test public void testGetIdField() { TenantAndIdEmittableKey key = new TenantAndIdEmittableKey("meta.data.tenantId", "test.id.key.field"); assertEquals(key.getIdField().toString(), "test.id.key.field"); }