### Question:
SpannerConnectionConfiguration { public String getFullyQualifiedDatabaseName() { return this.fullyQualifiedDbName; } private  SpannerConnectionConfiguration(String url, GoogleCredentials credentials); private  SpannerConnectionConfiguration(
      String projectId,
      String instanceName,
      String databaseName,
      GoogleCredentials credentials); String getProjectId(); String getInstanceName(); String getDatabaseName(); String getFullyQualifiedDatabaseName(); GoogleCredentials getCredentials(); int getPartialResultSetFetchSize(); Duration getDdlOperationTimeout(); Duration getDdlOperationPollInterval(); int getThreadPoolSize(); @Override boolean equals(Object o); @Override int hashCode();  }### Answer:
@Test public void nonNullConstructorParametersPassPreconditions() { SpannerConnectionConfiguration config = this.configurationBuilder .setProjectId("project1") .setInstanceName("an-instance") .setDatabaseName("db") .build(); assertThat(config.getFullyQualifiedDatabaseName()) .isEqualTo("projects/project1/instances/an-instance/databases/db"); }
@Test public void databaseUrlExtracting() { SpannerConnectionConfiguration config = this.configurationBuilder .setUrl("r2dbc:spanner: + "projects/my-project/instances/my-instance/databases/my-database") .build(); assertThat(config.getFullyQualifiedDatabaseName()) .isEqualTo("projects/my-project/instances/my-instance/databases/my-database"); }