/** Tests for repeated node and edge addition and removal in a {@link Graph}. */
@RunWith(JUnit4.class)

public final class GraphMutationTest {
  private static final int NUM_TRIALS = 50;
  private static final int NUM_NODES = 100;
  private static final int NUM_EDGES = 1000;
  private static final int NODE_POOL_SIZE = 1000; // must be >> NUM_NODES

  @Test
  public void directedGraph() {
    testGraphMutation(GraphBuilder.directed());
  }

                        <modelVersion>4.0.0</modelVersion>

                        <groupId>org.apache.maven.samples</groupId>
                        <artifactId>sample</artifactId>
                        <version>1.0.0</version>

                        <dependencyManagement>
                          <dependencies>
                            <dependency>
                              <groupId>org.junit</groupId>

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and install `jinja2`:

<div class="termy">

```console
$ pip install jinja2

---> 100%
```

</div>

## Using `Jinja2Templates`

* Import `Jinja2Templates`.
* Create a `templates` object that you can reuse later.
* Declare a `Request` parameter in the *path operation* that will return a template.

**FastAPI** 支持多种模板引擎。

Flask 等工具使用的 Jinja2 是最用的模板引擎。

在 Starlette 的支持下，**FastAPI** 应用可以直接使用工具轻易地配置 Jinja2。

## 安装依赖项

安装 `jinja2`：

<div class="termy">

```console
$ pip install jinja2

---> 100%
```

</div>

## 使用 `Jinja2Templates`

* 导入 `Jinja2Templates`
* 创建可复用的 `templates` 对象
* 在返回模板的*路径操作*中声明 `Request` 参数

func NewReader(readCloser io.ReadCloser, args *ReaderArgs) *Reader {
	readCloser = &syncReadCloser{rc: readCloser}
	d := jstream.NewDecoder(io.LimitReader(readCloser, maxDocumentSize), 0).ObjectAsKVS().MaxDepth(100)
	return &Reader{
		args:       args,
		decoder:    d,
		valueCh:    d.Stream(),
		readCloser: readCloser,
	}
}

// syncReadCloser will wrap a readcloser and make it safe to call Close while

        return LaRequestUtil.getOptionalRequest().map(request -> {
            String query = (String) request.getAttribute(key);
            if (query == null) {
                final StringBuilder buf = new StringBuilder(100);
                final Enumeration<String> names = request.getParameterNames();
                while (names.hasMoreElements()) {
                    final String name = names.nextElement();

                    logger.debug("Failed to process an input stream.", e);
                }
            }
        }
    }

    public String getOutput() {
        final StringBuilder buf = new StringBuilder(100);
        for (final String value : list) {
            buf.append(value).append("\n");
        }
        return buf.toString();
    }

    public boolean contains(final String value) {

 *
 * <p>The ticker can be configured so that the time is incremented whenever {@link #read} is called:
 * see {@link #setAutoIncrementStep}.
 *
 * <p>This class is thread-safe.
 *
 * @author Jige Yu
 * @since 10.0
 */
@ElementTypesAreNonnullByDefault
@GwtCompatible
public class FakeTicker extends Ticker {

  private final AtomicLong nanos = new AtomicLong();
  private volatile long autoIncrementStepNanos;

 * ExecutionException} or {@link UncheckedExecutionException}. This allows the client code to
 * continue to distinguish between exceptions and errors, even when they come from other threads.
 *
 * @author Chris Povirk
 * @since 10.0
 */
@GwtCompatible
@ElementTypesAreNonnullByDefault
public class ExecutionError extends Error {
  /*
   * Ideally, this class would have exposed only constructors that require a non-null cause. See

		}
		if rs != nil {
			t.Errorf("Case %d: Got non-nil rs though err != nil: %v", i, rs)
		}
	}

	invalidRangeSpecs := []string{
		"bytes=5-3",
		"bytes=10-10",
		"bytes=10-",
		"bytes=100-",
		"bytes=-0",
	}
	for i, irs := range invalidRangeSpecs {
		var err1, err2 error
		var rs *HTTPRangeSpec
		var o, l int64
		rs, err1 = parseRequestRangeSpec(irs)
		if err1 == nil {