*
   * <ul>
   *   <li>{@link #JAVA_EXT_DIRS} was deprecated in Java 8 and removed in Java 9. We have not
   *       confirmed whether it is available under older versions.
   *   <li>{@link #JAVA_COMPILER}, while still listed as required as of Java 15, is typically not
   *       available even under older version.
   *   <li>Any property may be cleared through APIs like {@link System#clearProperty}.

  }

  @Override
  public final boolean equals(@Nullable Object obj) {
    if (obj instanceof Subscriber) {
      Subscriber that = (Subscriber) obj;
      // Use == so that different equal instances will still receive events.
      // We only guard against the case that the same object is registered
      // multiple times
      return target == that.target && method.equals(that.method);
    }
    return false;
  }

     */
    SmbPipeResource getPipe(String url, int pipeType) throws CIFSException;

    /**
     * Close all connections and release resources associated with this context
     *
     * @return whether any connection was still in use
     * @throws CIFSException if an error occurs during cleanup
     */
    boolean close() throws CIFSException;

    /**
     * Get the configuration object for this context
     *

        // Assert - verify interaction with dependency
        verify(tree, times(1)).connectLogon(context);
        verify(tree, never()).close();
    }

    @Test
    @DisplayName("connectLogon accepts null context but still invokes")
    void connectLogon_withNull_isInvoked() throws Exception {
        // Act
        tree.connectLogon(null);

        // Assert - even null should be passed through to implementation

            return EndpointPair.unordered(requireNonNull(node), otherNode);
          }
        }
        // Add to visited set *after* processing neighbors so we still include self-loops.
        visitedNodes.add(node);
        if (!advance()) {
          visitedNodes = null;
          return endOfData();
        }
      }
    }
  }

```

////

## Recap { #recap }

Apart from all the fancy words used here, the **Dependency Injection** system is quite simple.

Just functions that look the same as the *path operation functions*.

But still, it is very powerful, and allows you to declare arbitrarily deeply nested dependency "graphs" (trees).

/// tip

All this might not seem as useful with these simple examples.

    // Test multiple registrations of the same engine
    public void test_multipleRegistrations() {
        testScriptEngine.register();
        testScriptEngine.register(); // Register again

        // Should still work without errors
        ScriptEngine retrieved = scriptEngineFactory.getScriptEngine("testEngine");
        assertNotNull(retrieved);
        assertEquals(testScriptEngine, retrieved);
    }

            java: 21
            root-pom: pom.xml
    runs-on: ${{ matrix.os }}
    env:
      ROOT_POM: ${{ matrix.root-pom }}
    steps:
      # Cancel any previous runs for the same branch that are still running.
      - name: 'Cancel previous runs'
        uses: styfle/cancel-workflow-action@85880fa0301c86cca9da44039ee3bb12d3bedbfa # 0.12.1
        with:
          access_token: ${{ github.token }}

## HTTPX { #httpx }

Even if your **FastAPI** application uses normal `def` functions instead of `async def`, it is still an `async` application underneath.

   * buildOrThrow(), or vice versa. So in particular, if we modify alternatingKeysAndValues to
   * eliminate duplicate keys (for buildKeepingLast()) then we have to ensure that a later call to
   * buildOrThrow() will still throw as if the duplicates had not been eliminated. And the exception
   * message must mention two values that were associated with the duplicate key in two different