if (StringUtil.isBlank(text)) {
            return null;
        }
        final String target = getDetectText(text);
        final LanguageResult result = detector.detect(target);
        if (logger.isDebugEnabled()) {
            logger.debug("detected lang:{}({}) from {}", result, result.getRawScore(), target);
        }
        return getSupportedLanguage(result.getLanguage());
    }

        return backingMap.getEntry(entryIndex);
      }
    };
  }

  /** Allocation-free implementation of {@code target.addAll(this)}. */
  void addTo(Multiset<? super E> target) {
    checkNotNull(target);
    for (int i = backingMap.firstIndex(); i >= 0; i = backingMap.nextIndex(i)) {
      target.add(backingMap.getKey(i), backingMap.getValue(i));
    }
  }

  @Override
  final int distinctElements() {

import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

import com.google.common.annotations.GwtCompatible;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import javax.annotation.Nonnull;
import javax.annotation.meta.TypeQualifierDefault;

/**
 * Marks all "top-level" types as non-null in a way that is recognized by Kotlin. Note that this

import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

import com.google.common.annotations.GwtCompatible;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import javax.annotation.Nonnull;
import javax.annotation.meta.TypeQualifierDefault;

/**
 * Marks all "top-level" types as non-null in a way that is recognized by Kotlin. Note that this

 * the License.
 */

package com.google.common.eventbus;

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Marks a method as an event subscriber.
 *
 * <p>The type of event will be indicated by the method's first (and only) parameter, which cannot

import static java.lang.annotation.ElementType.TYPE;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

import com.google.common.annotations.GwtCompatible;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import javax.annotation.Nonnull;
import javax.annotation.meta.TypeQualifierDefault;

/**
 * Marks all "top-level" types as non-null in a way that is recognized by Kotlin. Note that this

      @Override
      Appendable get(int sz) {
        return new StringBuilder(sz);
      }
    };

    abstract Appendable get(int sz);
  }

  @Param CopyStrategy strategy;
  @Param TargetSupplier target;

  @Param({"10", "1024", "1048576"})
  int size;

  String data;

  @BeforeExperiment
  public void setUp() {
    // precalculate some random strings of ascii characters.

      @Override
      Appendable get(int sz) {
        return new StringBuilder(sz);
      }
    };

    abstract Appendable get(int sz);
  }

  @Param CopyStrategy strategy;
  @Param TargetSupplier target;

  @Param({"10", "1024", "1048576"})
  int size;

  String data;

  @BeforeExperiment
  public void setUp() {
    // precalculate some random strings of ascii characters.

# 表单数据

接收的不是 JSON，而是表单字段时，要使用 `Form`。

/// info | "说明"

要使用表单，需预先安装 <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>。

例如，`pip install python-multipart`。

///

## 导入 `Form`

从 `fastapi` 导入 `Form`：

```Python hl_lines="1"
{!../../docs_src/request_forms/tutorial001.py!}
```

## 定义 `Form` 参数

创建表单（`Form`）参数的方式与 `Body` 和 `Query` 一样：

Par défaut, **FastAPI** convertirait automatiquement cette valeur de retour en JSON en utilisant le `jsonable_encoder` expliqué dans [JSON Compatible Encoder](../tutorial/encoder.md){.internal-link target=_blank}.

Ensuite, en arrière-plan, il mettra ces données JSON-compatible (par exemple un `dict`) à l'intérieur d'un `JSONResponse` qui sera utilisé pour envoyer la réponse au client.