[ji] should allow calling protected Java method with send

[kares]

... works on Java 8 but not on 10(+)

jruby 9.2.1.0-SNAPSHOT (2.5.0) 2018-09-11 055a178 Java HotSpot(TM) 64-Bit Server VM 10.0.1+10 on 10.0.1+10 +jit [linux-x86_64]
irb(main):001:0> Java::JavaUtilLogging::StreamHandler.new.setOutputStream
Traceback (most recent call last):
        6: from /home/kares/workspace/oss/jruby/bin/jirb:13:in `<main>'
        5: from org/jruby/RubyKernel.java:1178:in `catch'
        4: from org/jruby/RubyKernel.java:1178:in `catch'
        3: from org/jruby/RubyKernel.java:1412:in `loop'
        2: from org/jruby/RubyKernel.java:1040:in `eval'
        1: from (irb):1:in `evaluate'
NoMethodError (undefined method `setOutputStream' for #<Java::JavaUtilLogging::StreamHandler:0x18a645fd>)
irb(main):002:0> Java::JavaUtilLogging::StreamHandler.new.send :setOutputStream, nil
Traceback (most recent call last):
        6: from /home/kares/workspace/oss/jruby/bin/jirb:13:in `<main>'
        5: from org/jruby/RubyKernel.java:1178:in `catch'
        4: from org/jruby/RubyKernel.java:1178:in `catch'
        3: from org/jruby/RubyKernel.java:1412:in `loop'
        2: from org/jruby/RubyKernel.java:1040:in `eval'
        1: from (irb):2:in `evaluate'
NoMethodError (undefined method `setOutputStream' for #<Java::JavaUtilLogging::StreamHandler:0x4650a407>)

the first failure is fine (although if it would be marked as a protected instance method the failure would be different), setOutputStream is a protected Java method, the second would be more Ruby if it worked ... this all works on Java 8 - would argue the direct call working is not something JRuby encouraged or specified, nevertheless the second from should work everywhere - seems like we can not set it accessible (due JDK modularization?).

extracted from: https://github.com/jruby/jruby/issues/4851#issuecomment-420378298

related - similar accessibility issue on Java 10: https://github.com/jruby/jruby/issues/5284

[prashantvithani]

@kares Is there any workaround to solve this other than downgrading to Java-8?

[ckpeter]

Can confirm that this is happening on Java 11. Trinidad is throwing exception on startup due to this.

I could not find any workaround except downgrading to Java 8, or on Java 11, manually going into Trinidad logging code and disabling the call.

Here is another test case:

puts "JRuby: #{JRUBY_VERSION}"
puts "Java: #{java.lang.System.getProperty('java.runtime.version')}"
obj = java.util.logging::ConsoleHandler.new
puts "java.util.logging::ConsoleHandler.set_output_stream: #{obj.methods.include?(:set_output_stream)}"

C:\dir>ver

Microsoft Windows [Version 10.0.17134.523]

C:\dir>set JAVA_HOME=\bin\jdk8

C:\dir>jruby test.rb JRuby: 9.2.5.0 Java: 1.8.0_92-b14 java.util.logging::ConsoleHandler.set_output_stream: true

C:\dir>set JAVA_HOME=\bin\jdk11

C:\dir>jruby test.rb JRuby: 9.2.5.0 Java: 11.0.2+9-LTS java.util.logging::ConsoleHandler.set_output_stream: false

[headius]

I stumbled on this looking for bugs about calling protected methods but I believe opening the target package to JRuby should work. The syntax for a target class a.b.Cookie should be something like:

.jruby.java_opts

--add-opens <module>/a.b=org.jruby.dist

Where <module> could be:

• an actual module name, if the target library is in a loaded module
• a generated module name, usually based on the filename of the jar

It will depend on the target library and how it is being loaded.

The org.jruby.dist might be org.jruby.base or org.jruby.complete if you are launching JRuby as a Java application rather than via our bin/jruby launcher.