RFR JDK-8046282: SA update

[A. Sundararajan]

Since SA is java code, we could have it cleaner..

my 2 cents,
-Sundar

On Monday 09 June 2014 02:40 PM, Poonam Bajaj wrote:
> Hi Sundar,
>
> Yes, it is possible to do that. e.g.  G1YCType can be defined like this.
>
> public enum G1YCType {
>   Normal ("Normal"),
>   InitialMark ("Initial Mark"),
>   DuringMark ("During Mark"),
>   Mixed ("Mixed"),
>   G1YCTypeEndSentinel ("Unknown")
>
>   private final String value;
>
>   G1YCType(String val) {
>     this.value = val;
>   }
>   public String value() {
>     return value;
>   }
> }
>
> But, my purpose of having a class and an enum being used in that class 
> was to have the similar kind of code structure on the SA side as is 
> present on the hotspot side. e.g the above is defined as the following 
> on the hotspot side:
>
> 030 enum G1YCType {
> 031   Normal,
> 032   InitialMark,
> 033   DuringMark,
> 034   Mixed,
> 035   G1YCTypeEndSentinel
> 036 };
> 037
> 038 class G1YCTypeHelper {
> 039  public:
> 040   static const char* to_string(G1YCType type) {
> 041     switch(type) {
> 042       case Normal: return "Normal";
> 043       case InitialMark: return "Initial Mark";
> 044       case DuringMark: return "During Mark";
> 045       case Mixed: return "Mixed";
> 046       default: ShouldNotReachHere(); return NULL;
> 047     }
> 048   }
> 049 };
>
> And I have tried to replicate the same on the SA side so that one can 
> easily understand and map the definitions on both the sides.
>
>   27 public class G1YCTypeHelper {
>   28
>   29   public enum G1YCType {
>   30     Normal,
>   31     InitialMark,
>   32     DuringMark,
>   33     Mixed,
>   34     G1YCTypeEndSentinel
>   35   }
>   36
>   37   public static String toString(G1YCType type) {
>   38     switch (type) {
>   39     case Normal:
>   40       return "Normal";
>   41     case InitialMark:
>   42       return "Initial Mark";
>   43     case DuringMark:
>   44       return "During Mark";
>   45     case Mixed:
>   46       return "Mixed";
>   47     default:
>   48       return null;
>   49     }
>   50   }
>   51 }
>
>
> Please let me know if this is still a concern for you.
>
> Thanks,
> Poonam
>
> On 6/9/2014 10:38 AM, A. Sundararajan wrote:
>> The pattern of enum within a class and toString helper to return 
>> string description of it -- is used for many cases.
>>
>> Why not use enums with String accepting constructor and toString (or 
>> new method called "toDescription()) override? You could have add 
>> "Unknown" in these enums to map to an option that is available in VM 
>> -- but not in SA.
>>
>> Since it is a debugger it is expected to work with incomplete info.. 
>> so whereever you map a VM data structure element to java enum, you 
>> can map unknown enum constants to "Unknown" on Java side.  Of course, 
>> if there is a sentinel element defined in VM side, you could use that 
>> itself - no need for "Unknown" in such cases.
>>
>> It'd nice to simplify that class-within-enum pattern...
>>
>> -Sundar
>>
>> On Saturday 07 June 2014 02:48 PM, Poonam Bajaj wrote:
>>> Hi,
>>>
>>> Please review these changes for the bug 8046282 for JDK 9. These 
>>> changes add some definitions on the SA side and the supporting code 
>>> on the hotspot side.
>>>
>>> Webrev: http://cr.openjdk.java.net/~poonam/8046282/webrev.00/
>>> Bug: https://bugs.openjdk.java.net/browse/JDK-8046282
>>>
>>> Thanks,
>>> Poonam
>>>
>>