Stellen wir uns vor, wir möchten eine Abhängigkeit haben, die prüft, ob ein Query-Parameter `q` einen vordefinierten Inhalt hat.

Aber wir wollen diesen vordefinierten Inhalt per Parameter festlegen können.

## Eine „aufrufbare“ Instanz

In Python gibt es eine Möglichkeit, eine Instanz einer Klasse „aufrufbar“ („callable“) zu machen.

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.io.IOException;

/**
 * Package-protected abstract class that implements the line reading algorithm used by {@link
 * LineReader}. Line separators are per {@link java.io.BufferedReader}: line feed, carriage return,
 * or carriage return followed immediately by a linefeed.
 *
 * <p>Subclasses must implement {@link #handleLine}, call {@link #add} to pass character data, and

import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.io.IOException;

/**
 * Package-protected abstract class that implements the line reading algorithm used by {@link
 * LineReader}. Line separators are per {@link java.io.BufferedReader}: line feed, carriage return,
 * or carriage return followed immediately by a linefeed.
 *
 * <p>Subclasses must implement {@link #handleLine}, call {@link #add} to pass character data, and

import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * A queue which forwards all its method calls to another queue. Subclasses should override one or
 * more methods to modify the behavior of the backing queue as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingQueue} forward <b>indiscriminately</b> to the

   * numbers of keys and values without rehashing.
   *
   * @param expectedKeys the expected number of distinct keys
   * @param expectedValuesPerKey the expected average number of values per key
   * @throws IllegalArgumentException if {@code expectedKeys} or {@code expectedValuesPerKey} is
   *     negative
   */
  public static <K extends @Nullable Object, V extends @Nullable Object>

          <type>String</type>
          <defaultValue>per-lookup</defaultValue>
          <description>Specify the instantiation strategy.</description>
        </field>
        <field>
          <name>executionStrategy</name>
          <version>1.0.0/1.1.0</version>
          <type>String</type>
          <description>
            Specify the execution strategy: {@code once-per-session}, {@code always}.
          </description>

 {{{http://www.slf4j.org/manual.html#swapping}"SLF4J bindings"}}.

 Logging configuration loading is actually done by logging implementation, without any Maven extensions to support merging
 Maven installation configuration with per-user configuration for example:
 <<<$\{maven.conf}/logging>>> directory was added to core's classpath (see <<<$\{maven.home}/bin/m2.conf>>>). See your implementation
 documentation for details on file names, formats, and so on.

        assertEquals("org.apache.maven.plugin.jar.JarMojo", md.getImplementation());
        assertEquals("antrun", md.getComponentConfigurator());
        assertEquals("java", md.getLanguage());
        assertEquals("per-lookup", md.getInstantiationStrategy());
        assertEquals("some-goal", md.getExecuteGoal());
        assertEquals("generate-sources", md.getExecutePhase());
        assertEquals("cobertura", md.getExecuteLifecycle());

}

// API server instances report the versions they can decode and the version they
// encode objects to when persisting objects in the backend.
message StorageVersionStatus {
  // The reported versions per API server instance.
  // +optional
  // +listType=map
  // +listMapKey=apiServerID
  repeated ServerStorageVersion storageVersions = 1;

  // If all API server instances agree on the same encoding storage version,

/**
 * A {@link BlockingDeque} which forwards all its method calls to another {@code BlockingDeque}.
 * Subclasses should override one or more methods to modify the behavior of the backing deque as
 * desired per the <a href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>Warning:</b> The methods of {@code ForwardingBlockingDeque} forward <b>indiscriminately</b>