}

        @Test
        @DisplayName("should have valid plugin upgrade definitions")
        void shouldHaveValidPluginUpgradeDefinitions() throws Exception {
            List<PluginUpgrade> upgrades = PluginUpgradeStrategy.getPluginUpgrades();

            for (PluginUpgrade upgrade : upgrades) {
                assertNotNull(upgrade.groupId(), "Plugin upgrade should have groupId");

            if (isVersionBelow(currentVersion, upgrade.minVersion)) {
                Editor editor = new Editor(pomDocument);
                editor.setTextContent(versionElement, upgrade.minVersion);
                context.detail("Upgraded " + upgrade.groupId + ":" + upgrade.artifactId + " from " + currentVersion
                        + " to " + upgrade.minVersion + " in " + sectionName);
                return true;

                            phaseElement.textContent(newPhase);
                            context.detail("Upgraded phase: " + currentPhase + " → " + newPhase);
                            upgrades++;
                        }
                    }
                }
            }
        }

        return upgrades;
    }

                            || description.toLowerCase().contains("upgrade"),
                    "Description should mention model or upgrade");
        }
    }

    @Nested
    @DisplayName("Phase Upgrades")
    class PhaseUpgradeTests {

        @Test
        @DisplayName("should upgrade deprecated phases to Maven 4 equivalents in 4.1.0")

 * </ul>
 *
 * <h3>Plugin Upgrades</h3>
 * When {@code --plugins} option is enabled (or by default), upgrades plugins known to fail with Maven 4:
 * <ul>
 *   <li><strong>maven-exec-plugin</strong>: Upgrades to version 3.2.0 or higher</li>
 *   <li><strong>maven-enforcer-plugin</strong>: Upgrades to version 3.0.0 or higher</li>
 *   <li><strong>flatten-maven-plugin</strong>: Upgrades to version 1.2.7 or higher</li>

      }

    /**
     * Attempts to perform a web socket upgrade on the connection.
     * This will overwrite any previously set status, body, or streamHandler.
     */
    public fun webSocketUpgrade(listener: WebSocketListener): Builder =
      apply {
        status = "HTTP/1.1 101 Switching Protocols"
        setHeader("Connection", "Upgrade")
        setHeader("Upgrade", "websocket")
        webSocketListener = listener
      }

* `upgrade`: Upgrades

   [Gradle plugin][japicmp_gradle] to enforce binary compatibility.

 * **Java source compatibility** is the ability to upgrade Java uses of OkHttp 3.x to 4.x without
   changing `.java` files.

 * **Kotlin source compatibility** is the ability to upgrade Kotlin uses of OkHttp 3.x to 4.x
   without changing `.kt` files.

With a few small exceptions (below), OkHttp 4.x is both binary- and Java source-compatible with

    coders call this and we don't want their users to suffer.


## Version 4.0.0

_2019-06-26_

**This release upgrades OkHttp to Kotlin.** We tried our best to make fast and safe to upgrade
from OkHttp 3.x. We wrote an [upgrade guide][upgrading_to_okhttp_4] to help with the migration and a
[blog post][okhttp4_blog_post] to explain it.

 *  Fix: Target Java 8 bytecode for Java and Kotlin.

 *  New: Support request bodies on HTTP/1.1 connection upgrades.
 *  New: `EventListener.plus()` makes it easier to observe events in multiple listeners.
 *  Fix: Don't spam logs with _‘Method isLoggable in android.util.Log not mocked.’_ when using
    OkHttp in Robolectric and Paparazzi tests.
 *  Upgrade: [Kotlin 2.2.21][kotlin_2_2_21].
 *  Upgrade: [Okio 3.16.2][okio_3_16_2].