question of compiler code

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Thank you very much.
 


Date: Tue, 1 Sep 2009 18:18:32 -0700
From: Jonathan.Gibbons at Sun.COM
Subject: Re: question of compiler code
To: shangzhongyong at hotmail.com
CC: compiler-dev at openjdk.java.net

ÎÒ²»ÖªµÀ wrote: 




I am sorry, I do not speak English, but there are problems on the compiler.
Hope to get help,Thanks.
 
(source code version:openjdk-7-ea-src-b70-20_aug_2009)
1,
--------------------------------------source begin
  package com.sun.tools.javac.util;
   public interface LayoutCharacters
    /** Tabulator character.
     */
    final static byte TAB   = 0x8;
---------------------------------------source end
---------------------------------------question begin
 TAB   = 0x8;???
(ASCII-TAB==0x9??)
---------------------------------------question end

Yes, this is an error, but the value TAB is unused, so 
there is no incorrect behavior. The value should be 
fixed or deleted. I have filed CR 6878146.




 
2,
--------------------------------------source begin
package com.sun.tools.javac.parser;
    private void scanOperator() {
        while (true) {
            putC har(ch);
            Name newname = names.fromChars(sbuf, 0, sp);
            if (keywords.key(newname) == IDENTIFIER) {
                sp--;
                break;
            }
---------------------------------------source end
---------------------------------------question begin
keywords.key(newname) == IDENTIFIER;
Special Operator--> IDENTIFIER  ? 
---------------------------------------question end
This looks like defensive programming since Keywords.key(Name)
can return IDENTIFIER. The normal exit from the loop is here:
            if (!isSpecial(ch)) break;


 
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Thanks


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