#### `HeroBase` - the base class { #herobase-the-base-class }

Let's start with a `HeroBase` model that has all the **fields that are shared** by all the models:

* `name`
* `age`

{* ../../docs_src/sql_databases/tutorial002_an_py310.py ln[7:9] hl[7:9] *}

#### `Hero` - the *table model* { #hero-the-table-model }

    assertThat((long) arraysDim1 * arraysDim2).isNotEqualTo((long) (arraysDim1 * arraysDim2));

    double[][] arrays = new double[arraysDim1][];
    // it's shared to avoid using too much memory in tests
    double[] sharedArray = new double[arraysDim2];
    Arrays.fill(arrays, sharedArray);

    try {
      Doubles.concat(arrays);
      fail();

    super.doConnect();
}

@Override
public void close() throws IOException {
    try {
        super.close();
    } finally {
        // Don't release directory lease on close - it may be shared
        // Lease will be cleaned up by the lease manager
    }
}
```

### 5.2 Session Integration
```java
// In SmbSession.java
private DirectoryLeaseManager directoryLeaseManager;

It contains an `APIRouter` with some admin *path operations* that your organization shares between several projects.

For this example it will be super simple. But let's say that because it is shared with other projects in the organization, we cannot modify it and add a `prefix`, `dependencies`, `tags`, etc. directly to the `APIRouter`:

```Python hl_lines="3" title="app/internal/admin.py"

 * #runOneIteration} takes longer than its schedule defines, then subsequent executions may start
 * late. Also, all life cycle methods are executed with a lock held, so subclasses can safely modify
 * shared state without additional synchronization necessary for visibility to later executions of
 * the life cycle methods.
 *
 * <h3>Usage Example</h3>
 *

// BucketAlreadyExists the requested bucket name is not available.
type BucketAlreadyExists GenericError

func (e BucketAlreadyExists) Error() string {
	return "The requested bucket name is not available. The bucket namespace is shared by all users of the system. Please select a different name and try again."
}

// BucketAlreadyOwnedByYou already owned by you.
type BucketAlreadyOwnedByYou GenericError

            readBuffer.writeAll(receiveBuffer)
            if (wasEmpty) {
              notifyAll()
            }
          }
        }
      }

      // Update the connection flow control, as this is a shared resource.
      // Even if our stream doesn't need more data, others might.
      // But delay updating the stream flow control until that stream has been
      // consumed
      updateConnectionFlowControl(byteCount)

   * '\\u5432'} would yield the byte array {@code {0x54, 0x32}}.
   *
   * <p>If you need to convert and concatenate several values (possibly even of different types),
   * use a shared {@link java.nio.ByteBuffer} instance, or use {@link
   * com.google.common.io.ByteStreams#newDataOutput()} to get a growable buffer.
   */
  @GwtIncompatible // doesn't work
  public static byte[] toByteArray(char value) {

   * (short) 0x1234} would yield the byte array {@code {0x12, 0x34}}.
   *
   * <p>If you need to convert and concatenate several values (possibly even of different types),
   * use a shared {@link java.nio.ByteBuffer} instance, or use {@link
   * com.google.common.io.ByteStreams#newDataOutput()} to get a growable buffer.
   */
  @GwtIncompatible // doesn't work
  public static byte[] toByteArray(short value) {

  private static void testConcatOverflow(int arraysDim1, int arraysDim2) {
    assertThat((long) arraysDim1 * arraysDim2).isNotEqualTo((long) (arraysDim1 * arraysDim2));

    int[][] arrays = new int[arraysDim1][];
    // it's shared to avoid using too much memory in tests
    int[] sharedArray = new int[arraysDim2];
    Arrays.fill(arrays, sharedArray);

    try {
      Ints.concat(arrays);
      fail();