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</o:shapelayout></xml><![endif]--></head><body lang=DE link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>>Hi Markus,<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:10.0pt;font-family:"Courier New"'>>Should we drop the srcBigin/srcEnd parameters, as they can be replaced by a subSequence(srcBegin, srcEnd) call?<o:p></o:p></span></p><p class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Chen, I do understand your idea and while originally I had the same in mind (it really <i>is</i> appealing!), I came up with a draft using the <b>original</b> </span><span style='font-size:10.0pt;font-family:"Courier New"'>String.getChars()</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> signature instead, due to the following drawbacks:<o:p></o:p></span></p><ul type=disc><li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>There might exist (possibly lotsof) </span><span style='font-size:10.0pt;font-family:"Courier New"'>CharSequence.getChars(int, int, char[], int)</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> implementations already, as this problem (and the idea how to solve it) is anything but new. At least such implementations are </span><span style='font-size:10.0pt;font-family:"Courier New"'>String</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>, </span><span style='font-size:10.0pt;font-family:"Courier New"'>StringBuilder</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> and </span><span style='font-size:10.0pt;font-family:"Courier New"'>StringBuffer</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>. If we come up with a different signature, then <b>none</b> of these already existing performance boosters will get used by </span><span style='font-size:10.0pt;font-family:"Courier New"'>Reader.of(CharSequence)</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> automatically - at least until they come up with alias methods. Effectively this leads to (possibly lots) of alias methods. At least it leads to alias methods in </span><span style='font-size:10.0pt;font-family:"Courier New"'>String</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>, </span><span style='font-size:10.0pt;font-family:"Courier New"'>StringBuilder</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>, </span><span style='font-size:10.0pt;font-family:"Courier New"'>StringBuffer</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> and </span><span style='font-size:10.0pt;font-family:"Courier New"'>CharBuffer</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>. In contrast, when keeping the signature copied from </span><span style='font-size:10.0pt;font-family:"Courier New"'>String.getChars</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>, chances are good that (possibly lots of) implementations will <i>instantly</i> be supported by </span><span style='font-size:10.0pt;font-family:"Courier New"'>Reader.of(CharSequence)</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> without alias methods. At least, </span><span style='font-size:10.0pt;font-family:"Courier New"'>String</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>, </span><span style='font-size:10.0pt;font-family:"Courier New"'>StringBuilder</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> and </span><span style='font-size:10.0pt;font-family:"Courier New"'>StringBuffer</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> will be.<o:p></o:p></span></li><li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Since decades people are now very used to </span><span style='font-size:10.0pt;font-family:"Courier New"'>StringBuilder.getChars(int, int, char[], int)</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>, so (possibly a lot of) people might simply <i>expect</i> us to come up with that lengthy signature. These people might be rather confused (if not to say frustrated) when we now force them to write an intermediate </span><span style='font-size:10.0pt;font-family:"Courier New"'>subSequence(int, int)</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> for something that was "such simple" before.<o:p></o:p></span></li><li class=MsoNormal style='mso-margin-top-alt:auto;mso-margin-bottom-alt:auto;mso-list:l0 level1 lfo1'><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'>Custom implementations of </span><span style='font-size:10.0pt;font-family:"Courier New"'>CharSequence.subSequence</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> could come up with the (performance-wise "bad") idea of creating <b>copies</b> instead of views. At least it seems like </span><span style='font-size:10.0pt;font-family:"Courier New"'>AbstractStringBuilder</span><span style='font-size:12.0pt;font-family:"Times New Roman","serif"'> is doing that, so chances are "good" that custom libs will do that, too. For example, because they need it for safety. Or possibly, because they have a technical reason that <i>enforces</i> a copy. That would (possibly massively, depending on the actual class) spoil the idea of performance-boosting this RFC is all about.<o:p></o:p></span></li></ul><p class=MsoNormal><span style='color:#1F497D'>-Markus<o:p></o:p></span></p></div></body></html>