tidy up access to hooks

runtime/src/main/java/org/capnproto/CallContext.java

@@ -33,7 +33,7 @@ public class CallContext<Params, Results> {
     }
 
     public final <SubParams, Results> CompletableFuture<java.lang.Void> tailCall(Request<SubParams, Results> tailRequest) {
-        return this.hook.tailCall(tailRequest.getHook());
+        return this.hook.tailCall(tailRequest.hook);
     }
 
     public final void allowCancellation() {

runtime/src/main/java/org/capnproto/Capability.java

@@ -119,7 +119,7 @@ public final class Capability {
         protected <T> StreamingRequest<T> newStreamingCall(FromPointerBuilder<T> paramsBuilder,
                                                            long interfaceId, short methodId) {
             var request = hook.newCall(interfaceId, methodId);
-            return new StreamingRequest<> (paramsBuilder, request.params, request.hook);
+            return new StreamingRequest<> (paramsBuilder, request.getParams(), request.hook);
         }
     }
 

runtime/src/main/java/org/capnproto/Request.java

@@ -4,8 +4,8 @@ import java.util.concurrent.CompletableFuture;
 
 public class Request<Params, Results> {
 
-    Params params;
-    PipelineFactory<Results> pipelineFactory;
+    protected Params params;
+    private PipelineFactory<Results> pipelineFactory;
     RequestHook hook;
 
     public Request(Params params,
@@ -20,10 +20,6 @@ public class Request<Params, Results> {
         return params;
     }
 
-    public RequestHook getHook() {
-        return this.hook;
-    }
-
     public Results send() {
         var typelessPromise = this.hook.send();
         this.hook = null; // prevent reuse
@@ -31,6 +27,7 @@ public class Request<Params, Results> {
     }
 
     static <P, R> Request<P, R> newBrokenRequest(Throwable exc) {
+
         final MessageBuilder message = new MessageBuilder();
 
         var hook = new RequestHook() {

runtime/src/main/java/org/capnproto/Response.java

@@ -15,10 +15,6 @@ public class Response<Results> {
         return this.results;
     }
 
-    public ResponseHook getHook() {
-        return this.hook;
-    }
-
     static <R> Response<R> fromTypeless(FromPointerReader<R> resultsFactory,
                                         Response<AnyPointer.Reader> typeless) {
         return new Response<>(typeless.getResults().getAs(resultsFactory), typeless.hook);