LGTM 👍

@Runrioter @simonetripodi

What benefit does this change have for MyBatis users? I know If applied this change in existing implementation class, compile warning(unchecked warning) occur. I thinks have not benefit for user by only this change. Also at least, I think should wait to apply this change until next minor or major version up(Probably, we should be consider to modify the Plugin#wrap method together too).

WDYT?

@kazuki43zoo

What benefit does this change have for MyBatis users?

No. Just refactor this for coding easily without unnecessary casting

compile warning(unchecked warning) occur

Can you paste compile warning here ?

Can you paste compile warning here ?

• The above source code (inner class that use in MyBatis's test case)

  @Intercepts({
      @Signature(type = Map.class, method = "get", args = {Object.class})})
  public static class AlwaysMapPlugin implements Interceptor {
    @Override
    public Object intercept(Invocation invocation) {
      return "Always";
    }

    @Override
    public Object plugin(Object target) {
      return Plugin.wrap(target, this);
    }

    @Override
    public void setProperties(Properties properties) {
    }
  }

For prevent above waring, developer need to change existing source code as follow:

• Add @SuppressWaring("unchecked") on method level

    @Override
    @SuppressWarnings("unchecked")
    public Object plugin(Object target) {
      return Plugin.wrap(target, this);
    }

• Change method signature and adding cast that return value of Plugin#wrap (And need to add the @SuppressWaring("unchecked") for unchecked cast...)

    @Override
    @SuppressWarnings("unchecked")
    public <T> T plugin(T target) {
      return (T) Plugin.wrap(target, this);
    }

Libraries code will polishing but the user's point of view, it seems that there is no benefit to applying this change (in my opinion).

Thanks for your clarify. This is a little break when we override this method. I will modify Plugin#wrap too.