Javadoc for generated gRPC classes has warnings and errors

[idelpivnitskiy]

Motivation:

Generated gRPC classes have javadoc with illegal HTML characters
< and > and misses some @param. It causes build failures when
project compiles with -Xwerror flag.

Modifications:

• Replace parametrized types with non-parametrized for javadoc @link;
• Add missing @param;
• Include generated classes into testJavadoc task for
  servicetalk-grpc-protoc;

Result:

Project generates javadoc successfully when run with -Xwerror flag.

[Scottmitch]

looks like we still have some javadoc warnings due to generics <> still. here is how we can run javadoc validation during testing ... looks like protobuf-java also has some warnings so we won't be able to commit this yet but we can leave it commented out in the code to evaluate (and open an issue with protobuf-java).

diff --git a/servicetalk-grpc-protoc/build.gradle b/servicetalk-grpc-protoc/build.gradle
index e9e0ee541..1e024012b 100644
--- a/servicetalk-grpc-protoc/build.gradle
+++ b/servicetalk-grpc-protoc/build.gradle
@@ -108,3 +108,18 @@ afterEvaluate {
 clean {
   delete protobuf.generatedFilesBaseDir
 }
+
+sourceSets {
+  testJavaDocSourceSet {
+    java.srcDir file("$buildDir/generated/sources/proto")
+    sourceSets.test.allJava
+  }
+}
+
+task testJavadoc(type: Javadoc) {
+  source = sourceSets.testJavaDocSourceSet.allJava
+  classpath = sourceSets.test.compileClasspath
+  destinationDir = file("${buildDir}/tmp/testjavadoc")
+}
+
+test.finalizedBy(testJavadoc)

[Scottmitch]

lets see if build passes, we may have to deactivate testing javadoc as part of the build bcz protobuf-java has some javadoc issues. however the error detection doesn't always flag it...

> Task :servicetalk-grpc-protoc:testJavadoc
/Users/scott/git/servicetalk/servicetalk-grpc-protoc/build/generated/sources/proto/test/java/test/shared/TestShared.java:1507: warning: no @param for value
      public Builder setUntilValue(