Backport PR #16506 to 8.x: Avoid to access Java DeprecatedAlias value…

… other than Ruby's one

Update Settings to_hash method to also skip Java DeprecatedAlias and not just the Ruby one.
With PR #15679 was introduced org.logstash.settings.DeprecatedAlias which mirrors the behaviour of Ruby class Setting::DeprecatedAlias. The equality check at Logstash::Settings, as descibed in #16505 (comment), is implemented comparing the maps.
The conversion of Settings to the corresponding maps filtered out the Ruby implementation of DeprecatedAlias but not the Java one.
This PR adds also the Java one to the list of filter.

(cherry picked from commit 5d4825f)

Co-authored-by: Andrea Selva <[email protected]>

logstash-core/lib/logstash/settings.rb

@@ -154,7 +154,7 @@ def set_value(setting_name, value, graceful = false)
     def to_hash
       hash = {}
       @settings.each do |name, setting|
-        next if setting.kind_of? Setting::DeprecatedAlias
+        next if (setting.kind_of? Setting::DeprecatedAlias) || (setting.kind_of? Java::org.logstash.settings.DeprecatedAlias)
         hash[name] = setting.value
       end
       hash

logstash-core/spec/logstash/settings_spec.rb

@@ -62,6 +62,28 @@
     end
   end
 
+  describe "#to_hash" do
+    let(:java_deprecated_alias) { LogStash::Setting::Boolean.new("java.actual", true).with_deprecated_alias("java.deprecated") }
+    let(:ruby_deprecated_alias) { LogStash::Setting::PortRange.new("ruby.actual", 9600..9700).with_deprecated_alias("ruby.deprecated") }
+    let(:non_deprecated) { LogStash::Setting::Boolean.new("plain_setting", false) }
+
+    before :each do
+      subject.register(java_deprecated_alias)
+      subject.register(ruby_deprecated_alias)
+      subject.register(non_deprecated)
+    end
+
+    it "filter deprecated alias settings" do
+      generated_settings_hash = subject.to_hash
+
+      expect(generated_settings_hash).not_to have_key("java.deprecated")
+      expect(generated_settings_hash).not_to have_key("ruby.deprecated")
+      expect(generated_settings_hash).to have_key("java.actual")
+      expect(generated_settings_hash).to have_key("ruby.actual")
+      expect(generated_settings_hash).to have_key("plain_setting")
+    end
+  end
+
   describe "#get_subset" do
     let(:numeric_setting_1) { LogStash::Setting.new("num.1", Numeric, 1) }
     let(:numeric_setting_2) { LogStash::Setting.new("num.2", Numeric, 2) }