The client (browser) will know that the response comes from the correct server because it is using the cryptography they agreed using the **HTTPS certificate** before.

### Multiple Applications { #multiple-applications }

In the same server (or servers), there could be **multiple applications**, for example, other API programs or a database.

import java.util.Set;

/**
 * Filter to only retain objects in the given scope or better. This implementation allows the accumulation of multiple
 * scopes and their associated implied scopes, so that the user can filter apply a series of implication rules in a
 * single step. This should be a more efficient implementation of multiple standard {@link ScopeArtifactFilter}
 * instances ORed together.
 *
 */

  }

  /**
   * Returns the number of times {@link Cache} lookup methods have returned an uncached (newly
   * loaded) value, or null. Multiple concurrent calls to {@link Cache} lookup methods on an absent
   * value can result in multiple misses, all returning the results of a single cache load
   * operation.
   */
  public long missCount() {
    return missCount;
  }

  /**

  }

  /**
   * Returns the number of times {@link Cache} lookup methods have returned an uncached (newly
   * loaded) value, or null. Multiple concurrent calls to {@link Cache} lookup methods on an absent
   * value can result in multiple misses, all returning the results of a single cache load
   * operation.
   */
  public long missCount() {
    return missCount;
  }

  /**

        new SecureRandom().nextBytes(secondFileId);

        // When - set file ID multiple times
        assertDoesNotThrow(() -> {
            request.setFileId(firstFileId);
            request.setFileId(secondFileId);
            request.setFileId(testFileId);
        }, "Should handle multiple setFileId calls");
    }

    @Test
    @DisplayName("Should test interface with anonymous implementation")

```
KEY:
etcd  federate multiple clusters for IAM and Bucket DNS

ARGS:
endpoints*       (csv)       comma separated list of etcd endpoints e.g. "http://localhost:2379"
path_prefix      (path)      namespace prefix to isolate tenants e.g. "customer1/"

 *       <a href="https://developer.android.com/studio/build/shrink-code">R8 and Proguard</a>.
 *   <li>It doesn't offer a way to wait for multiple events before taking action. For example, it
 *       doesn't offer a way to wait for multiple producers to all report that they're "ready," nor
 *       does it offer a way to batch multiple events from a single producer together.
 *   <li>It doesn't support backpressure and other features needed for resilience.

        File file = cos.getFile();
        assertTrue(file.exists());
        cos.close();
    }

    @Test
    public void testMultipleWrites() throws IOException {
        // Multiple write calls should accumulate
        ContentOutputStream cos = new ContentOutputStream(10, Curl.tmpDir);
        cos.write(new byte[] { 0, 1, 2 });
        assertTrue(cos.isInMemory());

<div class="screenshot">
<img src="/img/tutorial/sql-databases/image01.png">
</div>

## Update the App with Multiple Models { #update-the-app-with-multiple-models }

Now let's **refactor** this app a bit to increase **security** and **versatility**.

      Integer uid = uids.get(obj);
      if (uid == null) {
        // One or more integer values could be skipped in the event of a race
        // to generate a UID for the same object from multiple threads, but
        // that shouldn't be a problem.
        uid = counter.getAndIncrement();
        Integer alreadySet = uids.putIfAbsent(obj, uid);
        if (alreadySet != null) {
          uid = alreadySet;