## What is "Dependency Injection" { #what-is-dependency-injection }

**"Dependency Injection"** means, in programming, that there is a way for your code (in this case, your *path operation functions*) to declare things that it requires to work and use: "dependencies".

And then, that system (in this case **FastAPI**) will take care of doing whatever is needed to provide your code with those needed dependencies ("inject" the dependencies).

		return healEntryResult{
			bytes:   sz,
			skipped: true,
		}
	}

	// Collect updates to tracker from concurrent healEntry calls
	results := make(chan healEntryResult, 1000)
	quitting := make(chan struct{})
	defer func() {
		close(results)
		<-quitting
	}()

	go func() {
		for res := range results {
			if res.entryDone {
				tracker.setObject(res.name)

     * AggregateFutureState.
     *
     * Here, we check that we're able to force AbstractFutureState to select SynchronizedHelper, and
     * below, we actually run the AbstractFutureTest methods under that scenario.
     */
    checkHelperVersion(NO_ATOMIC_REFERENCE_FIELD_UPDATER, "SynchronizedHelper");

    // Then, run the actual tests under each alternative classloader:

    /*

	// Perform callhome once and then keep running it at regular intervals.
	performCallhome(ctx)

	callhomeTimer := time.NewTimer(globalCallhomeConfig.FrequencyDur())
	defer callhomeTimer.Stop()

	for {
		if !globalCallhomeConfig.Enabled() {
			// Stop the processing as callhome got disabled
			return false
		}

		select {
		case <-ctx.Done():
			// indicates that we do not need to run callhome anymore

      this.safeMax = safeMax;
      return this;
    }

    /**
     * Sets the replacement string for any characters outside the 'safe' range that have no explicit
     * replacement. If {@code unsafeReplacement} is {@code null} then no replacement will occur, if
     * it is {@code ""} then the unsafe characters are removed from the output.
     *
     * @param unsafeReplacement the string to replace unsafe characters

  /*
   * This is a public type so that the Android test runner can create an instance directly as it
   * insists upon doing. It then runs the test, which behaves exactly like this package's existing
   * PackageSanityTests. (The test would run on the JVM, too, if not for the suppression below, and
   * that would be a problem because it violates small-test rules. Note that we strip the

/**
 * <p>
 *   Deferred is a class that represents a deferred computation.
 *   It is similar to a Promise in JavaScript.
 *   It allows you to register callbacks that will be executed when the computation is complete,
 *   either successfully (resolve) or with an error (reject).
 * </p>
 *
 * <p>
 *   The Deferred class has a Promise inner class that allows you to register callbacks

```JSON
{"item_id":3}
```

/// check

Notice that the value your function received (and returned) is `3`, as a Python `int`, not a string `"3"`.

So, with that type declaration, **FastAPI** gives you automatic request <abbr title="converting the string that comes from an HTTP request into Python data">"parsing"</abbr>.

///

## Data validation { #data-validation }

 * they are thin wrapper around {@link java.util.Collections#emptySet()}, {@link
 * Collections#singleton(Object)} and {@link java.util.LinkedHashSet} for empty, singleton and
 * regular sets respectively. For the sorted sets, it's a thin wrapper around {@link
 * java.util.TreeSet}.
 *
 * @see ImmutableSortedSet
 * @author Hayward Chan
 */
@SuppressWarnings("serial") // Serialization only done in GWT.

    if [ -z "$JAVA_HOME" ]; then
      if [ -x "/usr/libexec/java_home" ]; then
        export JAVA_HOME="`/usr/libexec/java_home`"
      else
        export JAVA_HOME="/Library/Java/Home"
      fi
    fi
    ;;
esac

if [ -z "$JAVA_HOME" ] ; then
  if [ -r /etc/gentoo-release ] ; then
    JAVA_HOME=`java-config --jre-home`
  fi
fi

if [ -z "$M2_HOME" ] ; then