Java7 classes should no longer need reflection

[pjfanning]

• Since Jackson 2.14, Java 8 is minimum needed
• with newer Java releases, it is better to minimise the use of Java reflection
• In theory, we could roll this code into parent classes but removing classes might be regarded as a breaking change - in the unlikely scenario, that someone has subclassed this part of the code

[cowtowncoder]

I agree with the goals. But would this be problematic for Android users?

[pjfanning]

I agree with the goals. But would this be problematic for Android users?

I don't know much about Android. I sort of assumed CI build was set up to check. I thought I saw mention of Animal Sniffer being used to verify compatibility with Android API level 26.

[pjfanning]

I'll close this. Looks like this Java7 support class is needed for Android compatibility.

      <plugin>
	<groupId>org.codehaus.mojo</groupId>
	<artifactId>animal-sniffer-maven-plugin</artifactId>
	<version>1.22</version>
	<configuration>
          <signature>
            <groupId>com.toasttab.android</groupId>
            <artifactId>gummy-bears-api-${version.android.sdk}</artifactId>
            <version>${version.android.sdk.signature}</version>
          </signature>
	  <ignores>
            <!-- These are only accessed (safely) via "Java7SupportImpl.java" so ignore
              -->
	    <ignore>java.beans.ConstructorProperties</ignore>
	    <ignore>java.beans.Transient</ignore>
	    <ignore>java.nio.file.FileSystemNotFoundException</ignore>
	    <ignore>java.nio.file.Path</ignore>
	    <ignore>java.nio.file.Paths</ignore>
	    <ignore>java.nio.file.spi.FileSystemProvider</ignore>
	  </ignores>
	</configuration>
      </plugin>

[pjfanning]

It's possible that the java.nio classes are actually ok. Animal Sniffer only picks up on the 2 java.beans classes when I empty the ignores list.

[ERROR] /Users/pj.fanning/code/jackson-databind/src/main/java/com/fasterxml/jackson/databind/ext/Java7SupportImpl.java:29: Undefined reference: java.beans.Transient
[ERROR] /Users/pj.fanning/code/jackson-databind/src/main/java/com/fasterxml/jackson/databind/ext/Java7SupportImpl.java:31: Undefined reference: boolean java.beans.Transient.value()
[ERROR] /Users/pj.fanning/code/jackson-databind/src/main/java/com/fasterxml/jackson/databind/ext/Java7SupportImpl.java:38: Undefined reference: java.beans.ConstructorProperties
[ERROR] /Users/pj.fanning/code/jackson-databind/src/main/java/com/fasterxml/jackson/databind/ext/Java7SupportImpl.java:52: Undefined reference: java.beans.ConstructorProperties
[ERROR] /Users/pj.fanning/code/jackson-databind/src/main/java/com/fasterxml/jackson/databind/ext/Java7SupportImpl.java:54: Undefined reference: String[] java.beans.ConstructorProperties.value()
[ERROR] Failed to execute goal org.codehaus.mojo:animal-sniffer-maven-plugin:1.22:check (default-cli) on project jackson-databind: Signature errors found. Verify them and ignore them with the proper annotation if needed. -> [Help 1]
[ERROR] 

[cowtowncoder]

Ok, I think there are 2 things we can consider then:

1. Remove Reflection for java.nio classes if they are ok with ADK 26
2. See which ADK (if any?) would allow annotations, and consider future work for like Jackson 2.16 -- we can definitely raised ADK minimum over releases

For (2) we should probably file a new issue for 2.16 for follow-up work.

[pjfanning]

replaced by #3708