### Question:
ElasticApmTracerBuilder { public ElasticApmTracer build() { return build(false); } ElasticApmTracerBuilder();  ElasticApmTracerBuilder(@Nullable String agentArguments); ElasticApmTracerBuilder configurationRegistry(ConfigurationRegistry configurationRegistry); ElasticApmTracerBuilder reporter(Reporter reporter); ElasticApmTracerBuilder withObjectPoolFactory(ObjectPoolFactory objectPoolFactory); ElasticApmTracerBuilder withLifecycleListener(LifecycleListener listener); ElasticApmTracer build(); ElasticApmTracer buildAndStart();  }### Answer:
@Test void testConfigFileLocation(@TempDir Path tempDir) throws IOException { Path file = Files.createFile(tempDir.resolve("elastic-apm-test.properties")); Files.write(file, List.of("instrument=false")); System.setProperty("elastic.apm." + CoreConfiguration.CONFIG_FILE, file.toString()); ConfigurationRegistry configurationRegistry = new ElasticApmTracerBuilder().build().getConfigurationRegistry(); CoreConfiguration config = configurationRegistry.getConfig(CoreConfiguration.class); assertThat(config.isInstrument()).isFalse(); configurationRegistry.getString(CoreConfiguration.CONFIG_FILE); assertThat(configurationRegistry.getString(CoreConfiguration.CONFIG_FILE)).isEqualTo(file.toString()); }
@Test void testTempAttacherPropertiesFile(@TempDir Path tempDir) throws Exception { Path file = Files.createFile(tempDir.resolve("elstcapm.tmp")); Files.write(file, List.of("instrument=false")); ConfigurationRegistry configurationRegistry = new ElasticApmTracerBuilder("c=" + file.toAbsolutePath()).build().getConfigurationRegistry(); CoreConfiguration config = configurationRegistry.getConfig(CoreConfiguration.class); assertThat(config.isInstrument()).isFalse(); }