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.

// Addr2line is a minimal simulation of the GNU addr2line tool,
// just enough to support pprof.
//
// Usage:
//
//	go tool addr2line binary
//
// Addr2line reads hexadecimal addresses, one per line and with optional 0x prefix,
// from standard input. For each input address, addr2line prints two output lines,
// first the name of the function containing the address and second the file:line

        // MS-SMB2 3.2.4.1.6: Alternative Channel Creation
        // Channel binding requires SMB2_SESSION_FLAG_BINDING (0x01) in session setup

        // Calculate channel binding hash per MS-SMB2 3.2.5.3.1
        byte[] bindingInfo = calculateBindingInfo(channel);
        byte[] bindingHash = calculateBindingHash(bindingInfo);
        channel.setBindingHash(bindingHash);

        assertEquals(6, packet.length);
    }

    @Test
    void writeTrailerWireFormatShouldReturnZero() {
        // Test that writeTrailerWireFormat always returns 0, as per its implementation.
        SessionRetargetResponsePacket packet = new SessionRetargetResponsePacket();
        assertEquals(0, packet.writeTrailerWireFormat(new byte[0], 0));
    }

    @Test

import org.jspecify.annotations.Nullable;

/**
 * A set multimap which forwards all its method calls to another set multimap. Subclasses should
 * override one or more methods to modify the behavior of the backing multimap as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class does <i>not</i> forward calls to {@code

import org.jspecify.annotations.Nullable;

/**
 * An iterator which forwards all its method calls to another iterator. Subclasses should override
 * one or more methods to modify the behavior of the backing iterator as desired per the <a
 * href="http://en.wikipedia.org/wiki/Decorator_pattern">decorator pattern</a>.
 *
 * <p><b>{@code default} method warning:</b> This class forwards calls to <i>only some</i> {@code

      safeMax = -1;
      safeMin = Integer.MAX_VALUE;
    }
    this.safeMin = safeMin;
    this.safeMax = safeMax;

    // This is a bit of a hack but lets us do quicker per-character checks in
    // the fast path code. The safe min/max values are very unlikely to extend
    // into the range of surrogate characters, but if they do we must not test

 *     .add("publicobject.com", "sha256/lCppFqbkrlJ3EcVFAkeip0+44VaoJUymbnOaEUk7tEU=")
 *     .build();
 * ```
 *
 * ## Domain Patterns
 *
 * Pinning is per-hostname and/or per-wildcard pattern. To pin both `publicobject.com` and
 * `www.publicobject.com` you must configure both hostnames. Or you may use patterns to match
 * sets of related domain names. The following forms are permitted:
 *

      return arrayListValues(DEFAULT_EXPECTED_VALUES_PER_KEY);
    }

    /**
     * Uses an {@link ArrayList} to store value collections, initialized to expect the specified
     * number of values per key.
     *
     * @throws IllegalArgumentException if {@code expectedValuesPerKey < 0}
     */
    public ListMultimapBuilder<K0, @Nullable Object> arrayListValues(int expectedValuesPerKey) {

      return arrayListValues(DEFAULT_EXPECTED_VALUES_PER_KEY);
    }

    /**
     * Uses an {@link ArrayList} to store value collections, initialized to expect the specified
     * number of values per key.
     *
     * @throws IllegalArgumentException if {@code expectedValuesPerKey < 0}
     */
    public ListMultimapBuilder<K0, @Nullable Object> arrayListValues(int expectedValuesPerKey) {