JDK 9 RFR of JDK-8155516: Suppress warnings from uses of deprecated Class.newInstance langtools

[Jonathan Gibbons]

Thanks for the update.

-- Jon

On 05/02/2016 05:57 PM, Joseph D. Darcy wrote:
> Hi Jon,
>
> I filed the follow-up issue
>
>     JDK-8155880: Fix langtools usage of the deprecated 
> Class.newInstance method
>
> Cheers,
>
> -Joe
>
> On 4/27/2016 4:59 PM, Jonathan Gibbons wrote:
>> Joe,
>>
>> I guess this is OK for now, but as a general policy for langtools, I 
>> hope we are not going to see @SuppressWarnings proliferating 
>> throughout the code.  If a method has been deprecated, it is 
>> presumably for a good reason (<cough> Optional.get </cough>) and 
>> there should in general be a replacement, and we should endeavor to 
>> improve the quality of the code base by using the recommended 
>> replacements, rather than perpetuating the sins of our predecessors.
>>
>> As for @SuppressWarnings, the review yesterday had a credible use of 
>> the annotation insofar as the replacement method was not available in 
>> JDK 8, which (for the duration of JDK 9 development) is our bootstrap 
>> compiler.
>>
>> For all of Stuart's protestations that these are not breaking 
>> changes, we are sure doing a lot of high priority reacting to 
>> non-breaking changes!
>>
>> -- Jon
>>
>> On 04/27/2016 04:21 PM, Jonathan Gibbons wrote:
>>> What is the recommended approach for avoiding the issue, as compared 
>>> to sweeping it under the carpet?
>>>
>>> -- Jon
>>>
>>>
>>> On 04/27/2016 02:27 PM, Joseph D. Darcy wrote:
>>>> Hello,
>>>>
>>>> As part of the effort to address
>>>>
>>>>     JDK-6850612: Deprecate Class.newInstance since it violates the 
>>>> checked exception language contract
>>>>
>>>> the uses of Class.newInstance in the langtools repo have to be 
>>>> address in some way, either by suppressing the resulting warning or 
>>>> by refactoring the code to use other recommended idioms.
>>>>
>>>> Please review the fix for
>>>>
>>>>     JDK-8155516: Suppress warnings from uses of deprecated 
>>>> Class.newInstance langtools
>>>>     http://cr.openjdk.java.net/~darcy/8155516.0/
>>>>
>>>> which takes the suppression approach.
>>>>
>>>> Patch below.
>>>>
>>>> Thanks,
>>>>
>>>> -Joe
>>>>
>>>> --- 
>>>> old/src/java.compiler/share/classes/javax/tools/ToolProvider.java 
>>>> 2016-04-27 14:16:21.269126143 -0700
>>>> +++ 
>>>> new/src/java.compiler/share/classes/javax/tools/ToolProvider.java 
>>>> 2016-04-27 14:16:21.177126140 -0700
>>>> @@ -123,7 +123,9 @@
>>>>      private static <T> T getSystemTool(Class<T> clazz, String 
>>>> moduleName, String className) {
>>>>          if (useLegacy) {
>>>>              try {
>>>> -                return Class.forName(className, true, 
>>>> ClassLoader.getSystemClassLoader()).asSubclass(clazz).newInstance();
>>>> +                @SuppressWarnings("deprecation")
>>>> +                T result = Class.forName(className, true, 
>>>> ClassLoader.getSystemClassLoader()).asSubclass(clazz).newInstance();
>>>> +                return result;
>>>>              } catch (ReflectiveOperationException e) {
>>>>                  throw new Error(e);
>>>>              }
>>>> --- 
>>>> old/src/jdk.compiler/share/classes/com/sun/tools/javac/processing/JavacProcessingEnvironment.java 
>>>> 2016-04-27 14:16:21.573126153 -0700
>>>> +++ 
>>>> new/src/jdk.compiler/share/classes/com/sun/tools/javac/processing/JavacProcessingEnvironment.java 
>>>> 2016-04-27 14:16:21.489126150 -0700
>>>> @@ -282,6 +282,7 @@
>>>>
>>>>          if (options.isSet(XPRINT)) {
>>>>              try {
>>>> +                @SuppressWarnings("deprecation")
>>>>                  Processor processor = 
>>>> PrintingProcessor.class.newInstance();
>>>>                  processorIterator = List.of(processor).iterator();
>>>>              } catch (Throwable t) {
>>>> @@ -549,8 +550,9 @@
>>>>                          try {
>>>>                              Class<?> processorClass = 
>>>> processorCL.loadClass(processorName);
>>>>                              ensureReadable(processorClass);
>>>> -                            processor =
>>>> -                                (Processor) 
>>>> (processorClass.newInstance());
>>>> + @SuppressWarnings("deprecation")
>>>> +                            Object tmp = 
>>>> processorClass.newInstance();
>>>> +                            processor = (Processor) tmp;
>>>>                          } catch (ClassNotFoundException cnfe) {
>>>> log.error("proc.processor.not.found", processorName);
>>>>                              return false;
>>>> --- 
>>>> old/src/jdk.compiler/share/classes/com/sun/tools/sjavac/options/Option.java 
>>>> 2016-04-27 14:16:21.881126163 -0700
>>>> +++ 
>>>> new/src/jdk.compiler/share/classes/com/sun/tools/sjavac/options/Option.java 
>>>> 2016-04-27 14:16:21.797126161 -0700
>>>> @@ -151,6 +151,7 @@
>>>>              // Construct transformer
>>>>              try {
>>>>                  Class<?> trCls = Class.forName(classname);
>>>> +                @SuppressWarnings("deprecation")
>>>>                  Transformer transformer = (Transformer) 
>>>> trCls.newInstance();
>>>>                  transformer.setExtra(extra);
>>>>                  helper.addTransformer(suffix, transformer);
>>>> --- 
>>>> old/src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/toolkit/taglets/TagletManager.java 
>>>> 2016-04-27 14:16:22.181126173 -0700
>>>> +++ 
>>>> new/src/jdk.javadoc/share/classes/jdk/javadoc/internal/doclets/toolkit/taglets/TagletManager.java 
>>>> 2016-04-27 14:16:22.097126171 -0700
>>>> @@ -247,6 +247,7 @@
>>>>              tagClassLoader = fileManager.getClassLoader(TAGLET_PATH);
>>>>              Class<?> customTagClass = 
>>>> tagClassLoader.loadClass(classname);
>>>>              ensureReadable(customTagClass);
>>>> +            @SuppressWarnings("deprecation")
>>>>              Object instance = customTagClass.newInstance();
>>>>              Taglet newLegacy = new 
>>>> UserTaglet((jdk.javadoc.doclet.taglet.Taglet)instance);
>>>>              String tname = newLegacy.getName();
>>>> --- 
>>>> old/src/jdk.javadoc/share/classes/jdk/javadoc/internal/tool/Start.java 
>>>> 2016-04-27 14:16:22.481126183 -0700
>>>> +++ 
>>>> new/src/jdk.javadoc/share/classes/jdk/javadoc/internal/tool/Start.java 
>>>> 2016-04-27 14:16:22.393126180 -0700
>>>> @@ -252,7 +252,9 @@
>>>>              initMessager();
>>>>              messager.setLocale(locale);
>>>>              try {
>>>> -                doclet = (Doclet) docletClass.newInstance();
>>>> +                @SuppressWarnings("deprecation")
>>>> +                Object o = docletClass.newInstance();
>>>> +                doclet = (Doclet) o;
>>>>              } catch (InstantiationException | 
>>>> IllegalAccessException exc) {
>>>>                  exc.printStackTrace();
>>>>                  if (!apiMode) {
>>>>
>>>
>>
>