* be used to decide whether to apply a test to a given class-under-test.
 *
 * <p>This is needed because annotations can't implement interfaces, which is also why reflection is
 * used to extract values from the properties of the various annotations.
 *
 * @author George van den Driessche
 */
@Target(value = {ElementType.ANNOTATION_TYPE})
@Retention(value = RetentionPolicy.RUNTIME)
@Documented
@GwtCompatible

    // requireNonNull accommodates Android's @RecentlyNullable annotation on ThreadLocal.get
    return requireNonNull(DEST_TL.get());
  }

  /**
   * A thread-local destination buffer to keep us from creating new buffers. The starting size is
   * 1024 characters. If we grow past this we don't put it back in the threadlocal, we just keep
   * going and grow as needed.
   */
  private static final ThreadLocal<char[]> DEST_TL =

 * be used to decide whether to apply a test to a given class-under-test.
 *
 * <p>This is needed because annotations can't implement interfaces, which is also why reflection is
 * used to extract values from the properties of the various annotations.
 *
 * @author George van den Driessche
 */
@Target(value = {ElementType.ANNOTATION_TYPE})
@Retention(value = RetentionPolicy.RUNTIME)
@Documented
@GwtCompatible

 * be primitive. If this annotation is applied to methods with zero parameters, or more than one
 * parameter, the object containing the method will not be able to register for event delivery from
 * the {@link EventBus}.
 *
 * <p>Unless also annotated with @{@link AllowConcurrentEvents}, event subscriber methods will be
 * invoked serially by each event bus that they are registered with.
 *
 * @author Cliff Biffle

		//	ExpectedRegexp: regexp.MustCompile("Configure istioctl defaults"),
		//	WantException:  false,
		//},
		{ // case 1
			Args: strings.Split("list", " "),
			ExpectedOutput: `FLAG                    VALUE            FROM
authority                                default
cert-dir                                 default
insecure                                 default
istioNamespace          istio-system     default

import org.codelibs.fess.crawler.entity.ExtractData;
import org.codelibs.fess.crawler.exception.CrawlerSystemException;
import org.codelibs.fess.crawler.exception.ExtractException;

/**
 * Gets a text from . file.
 *
 * @author shinsuke
 *
 */
public class MsVisioExtractor extends AbstractExtractor {

    /*
     * (non-Javadoc)
     *

  integrity sha512-OrZaX2Mb+rJCpH/6CpSqt9xFVpN++x01XnN2ie9g6P5/3xelLAkXWVADpdz1IHD/KFfEXyE6V0U01OQ3UO2rEg==
  dependencies:
    resolve-from "^5.0.0"

resolve-from@^5.0.0:
  version "5.0.0"
  resolved "https://registry.yarnpkg.com/resolve-from/-/resolve-from-5.0.0.tgz#c35225843df8f776df21c57557bc087e9dfdfc69"
  integrity sha512-qYg9KP24dD5qka9J47d0aVky0N+b4fTU89LN9iDnjB5waksiC49rvMB0PrUJQGoTmH50XPiqOvAjDfaijGxYZw==

                Set.of("{aaa TO *}"), //
                buildQuery("{aaa TO *}"));

        assertQueryContext(

      file.exists();
      fail("Did not get expected SecurityException");
    } catch (SecurityException expected) {
    }
    ClassPath classPath = ClassPath.from(getClass().getClassLoader());
    // ClassPath may contain resources from the boot class loader; just not from the class path.
    for (ResourceInfo resource : classPath.getResources()) {
      assertThat(resource.getResourceName()).doesNotContain("com/google/common/reflect/");
    }

然后，您可以调用该 Python 程序：

<div class="termy">

```console
// 这里我们还没有设置环境变量
$ python main.py

// 因为我们没有设置环境变量，所以我们得到默认值

Hello World from Python

// 但是如果我们先创建一个环境变量
$ export MY_NAME="Wade Wilson"

// 然后再次调用程序
$ python main.py

// 现在它可以读取环境变量

Hello Wade Wilson from Python
```

</div>

由于环境变量可以在代码之外设置，但可以由代码读取，并且不需要与其他文件一起存储（提交到 `git`），因此通常将它们用于配置或设置。