Bring codebase up to more recent Java standards (#2422)

This includes using the new switch format (though IntelliJ does not yet
understand patterns including default so those aren't used), multiline strings,
replacing some unnecessary type declarations with <>, converting some classes to
records, replacing some Guava predicates with native Java code, and some other
miscellaneous Code Inspection fixes.

prober/src/main/java/google/registry/monitoring/blackbox/ProbingStep.java

@@ -72,9 +72,12 @@ public record ProbingStep(
   }
 
   @Override
-  public final String toString() {
+  public String toString() {
     return String.format(
-        "ProbingStep with Protocol: %s\n" + "OutboundMessage: %s\n",
+        """
+            ProbingStep with Protocol: %s
+            OutboundMessage: %s
+            """,
         protocol(), messageTemplate().getClass().getName());
   }
 

prober/src/main/java/google/registry/monitoring/blackbox/connection/ProbingAction.java

@@ -202,10 +202,12 @@ public abstract class ProbingAction implements Callable<ChannelFuture> {
   @Override
   public final String toString() {
     return String.format(
-        "ProbingAction with delay: %d\n"
-            + "outboundMessage: %s\n"
-            + "protocol: %s\n"
-            + "host: %s\n",
+        """
+            ProbingAction with delay: %d
+            outboundMessage: %s
+            protocol: %s
+            host: %s
+            """,
         delay().getStandardSeconds(), outboundMessage(), protocol(), host());
   }
 
@@ -268,7 +270,7 @@ public abstract class ProbingAction implements Callable<ChannelFuture> {
       if (channel == null) {
         bootstrap
             .handler(
-                new ChannelInitializer<Channel>() {
+                new ChannelInitializer<>() {
                   @Override
                   protected void initChannel(Channel outboundChannel) {
                     // Uses Handlers from Protocol to fill pipeline in order of provided handlers.

prober/src/main/java/google/registry/monitoring/blackbox/module/EppModule.java

@@ -264,11 +264,6 @@ public class EppModule {
     return new EppRequestMessage("hello", greetingResponse, null, (a, b) -> ImmutableMap.of());
   }
 
-  /**
-   * Set of all possible {@link EppRequestMessage}s paired with their expected {@link
-   * EppResponseMessage}s.
-   */
-
   /** {@link Provides} login {@link EppRequestMessage} with expected response of success. */
   @Provides
   @Named("loginSuccess")

prober/src/test/java/google/registry/monitoring/blackbox/handler/EppActionHandlerTest.java

@@ -75,20 +75,25 @@ class EppActionHandlerTest {
   private Document getResponse(EppResponseMessage response, boolean fail, String clTrid)
       throws Exception {
     switch (response.name()) {
-      case "greeting":
+      case "greeting" -> {
         if (fail) {
           return EppUtils.getBasicResponse(true, clTrid, SERVER_ID);
         } else {
           return EppUtils.getGreeting();
         }
-      case "domainExists":
+      }
+      case "domainExists" -> {
         return EppUtils.getDomainCheck(!fail, clTrid, SERVER_ID, DOMAIN_NAME);
-      case "domainNotExists":
+      }
+      case "domainNotExists" -> {
         return EppUtils.getDomainCheck(fail, clTrid, SERVER_ID, DOMAIN_NAME);
-      case "success":
+      }
+      case "success" -> {
         return EppUtils.getBasicResponse(!fail, clTrid, SERVER_ID);
-      default:
+      }
+      default -> {
         return EppUtils.getBasicResponse(fail, clTrid, SERVER_ID);
+      }
     }
   }
 

prober/src/test/java/google/registry/monitoring/blackbox/message/TestMessage.java

@@ -14,8 +14,6 @@
 
 package google.registry.monitoring.blackbox.message;
 
-import google.registry.monitoring.blackbox.exception.UndeterminedStateException;
-
 /**
  * {@link InboundMessageType} and {@link OutboundMessageType} type for the purpose of containing
  * String messages to be passed down channel
@@ -34,7 +32,7 @@ public class TestMessage implements OutboundMessageType, InboundMessageType {
   }
 
   @Override
-  public OutboundMessageType modifyMessage(String... args) throws UndeterminedStateException {
+  public OutboundMessageType modifyMessage(String... args) {
     message = args[0];
     return this;
   }

prober/src/test/java/google/registry/monitoring/blackbox/testserver/TestServer.java

@@ -56,7 +56,7 @@ public class TestServer {
       ImmutableList<? extends ChannelHandler> handlers) {
     // Creates ChannelInitializer with handlers specified
     ChannelInitializer<LocalChannel> serverInitializer =
-        new ChannelInitializer<LocalChannel>() {
+        new ChannelInitializer<>() {
           @Override
           protected void initChannel(LocalChannel ch) {
             for (ChannelHandler handler : handlers) {