### EventListener.Factory

In the preceding example we used a field, `callStartNanos`, to track the elapsed time of each event. This is handy, but it won’t work if multiple calls are executing concurrently. To accommodate this, use a `Factory` to create a new `EventListener` instance for each `Call`. This allows each listener to keep call-specific state.

pkg crypto/x509, method (InsecureAlgorithmError) Error() string
pkg crypto/x509, method (SignatureAlgorithm) String() string
pkg crypto/x509, type InsecureAlgorithmError int
pkg database/sql, method (*DB) SetConnMaxLifetime(time.Duration)
pkg debug/dwarf, const ClassUnknown = 0
pkg debug/dwarf, const ClassUnknown Class
pkg debug/elf, const COMPRESS_HIOS = 1879048191
pkg debug/elf, const COMPRESS_HIOS CompressionType

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.opensearch.config.bsentity.dbmeta;

import java.time.LocalDateTime;
import java.util.List;
import java.util.Map;

import org.codelibs.fess.opensearch.config.exentity.ElevateWord;
import org.dbflute.Entity;
import org.dbflute.dbmeta.AbstractDBMeta;

import assertk.assertions.isEqualTo
import assertk.assertions.isInstanceOf
import assertk.assertions.isNotSameAs
import java.io.IOException
import java.net.Proxy
import java.security.cert.X509Certificate
import java.time.Duration
import kotlin.test.assertFailsWith
import mockwebserver3.MockResponse
import mockwebserver3.MockWebServer
import mockwebserver3.SocketEffect.CloseSocket
import mockwebserver3.junit5.StartStop

 * either express or implied. See the License for the specific language
 * governing permissions and limitations under the License.
 */
package org.codelibs.fess.opensearch.log.bsentity.dbmeta;

import java.time.LocalDateTime;
import java.util.List;
import java.util.Map;

import org.codelibs.fess.opensearch.log.exentity.ClickLog;
import org.dbflute.Entity;
import org.dbflute.dbmeta.AbstractDBMeta;

OkHttp 4.x upgrades our implementation language from Java to Kotlin and keeps everything else the
same. We’ve chosen Kotlin because it gives us powerful new capabilities while integrating closely
with Java.

We spent a lot of time and energy on retaining strict compatibility with OkHttp 3.x. We’re even
keeping the package name the same: `okhttp3`!

There are three kinds of compatibility we’re tracking:

import org.jspecify.annotations.Nullable;

/**
 * Executor ensuring that all Runnables submitted are executed in order, using the provided
 * Executor, and sequentially such that no two will ever be running at the same time.
 *
 * <p>Tasks submitted to {@link #execute(Runnable)} are executed in FIFO order.
 *
 * <p>The execution of tasks is done by one thread as long as there are tasks left in the queue.

        Smb2LeaseKey key = leaseManager.requestLease(path, requestedState);
        assertNotNull(leaseManager.getLease(key));

        // Wait a bit and then cleanup with a very short expiration time
        Thread.sleep(10);
        int cleaned = leaseManager.cleanupExpiredLeases(1); // 1ms expiration

        assertEquals(1, cleaned);
        assertNull(leaseManager.getLease(key));
    }

    @Test

            // Submit a write that will throw inside the writer thread
            w.write(payload, payload.length, out);

            // Give the writer thread time to process and set exception
            w.wait(100);
        }

        // Wait a bit more to ensure exception is captured
        Thread.sleep(100);

The same models are shared among requests, so, it's not one model per request, or one per user or something similar.

Let's imagine that loading the model can **take quite some time**, because it has to read a lot of **data from disk**. So you don't want to do it for every request.