@Test
  public void getPropertiesFileShouldUsePathInSystemProperty() throws Exception {
    File propertiesFile = temporaryFolder.newFile("test.properties");
    System.setProperty(PROPERTIES_FILE_PROPERTY, propertiesFile.getCanonicalPath());
    new Properties().store(new FileWriter(propertiesFile, false), testName.getMethodName());

    String value = DistributedSystem.getPropertiesFile();

    assertThat(value).isEqualTo(propertiesFile.getCanonicalPath());
  }
Integration tests for DistributedSystem class. These tests require file system I/O.
geode-core/src/integrationTest/java/org/apache/geode/distributed/DistributedSystemIntegrationTest.java