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Merge pull request giantray#3 from zhongjianluxian/why-is-printing-b-dramatically-slower-than-printing

Update why-is-printing-b-dramatically-slower-than-printing.md, translated the second most voted answer

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`@@ -51,7 +51,7 @@`
`51`	`51`	`- 我在Netbeans 7.2中运行测试,由控制台显示输出`
`52`	`52`	- 我使用了`System.nanoTime()`来计算时间
`53`	`53`
`54`		`-## 解答`
	`54`	`+## 解答一`
`55`	`55`
`56`	`56`	纯粹的推测是因为你使用的终端尝试使用[单词换行][1]而不是字符换行,并且它认为`B`是一个单词而`#`却不是。所以当它到达行尾并且寻找一个换行的地方的时候,如果是`#`就可以马上换行;而如果是`B`,它则需要花更长时间搜索,因为可能会有更多的内容才能换行(在某些终端会非常费时,比如说它会先输出退格再输出空格去覆盖被换行的那部分字符)。
`57`	`57`
`@@ -61,4 +61,54 @@`
`61`	`61`	`[1]: http://en.wikipedia.org/wiki/Word_wrap`
`62`	`62`
`63`	`63`
	`64`	`+##解答二`
	`65`	`+`
	`66`	+我用Eclipse和Netbeans 8.0.2做了测试,他们的Java版本都是1.8;我用了`System.nanoTime()`来计时。
	`67`	`+`
	`68`	`+##Eclipse:`
	`69`	`+`
	`70`	`+我得到了用时相同的结果 - 大约1.564秒。`
	`71`	`+`
	`72`	`+##Netbeans:`
	`73`	`+`
	`74`	`+* 使用"#": 1.536秒`
	`75`	`+* 使用"B": 44.164秒`
	`76`	`+`
	`77`	`+所以看起来像是Netbeans输出到控制台的性能问题。`
	`78`	`+`
	`79`	+在做了更多研究以后我发现问题所在是Netbeans [换行][1] 的最大缓存(这并不限于`System.out.println`命令),参见以下代码:
	`80`	`+`
	`81`	`+ for (int i = 0; i < 1000; i++) {`
	`82`	`+ long t1 = System.nanoTime();`
	`83`	`+ System.out.print("BBB......BBB"); \\<-contain 1000 "B"`
	`84`	`+ long t2 = System.nanoTime();`
	`85`	`+ System.out.println(t2-t1);`
	`86`	`+ System.out.println("");`
	`87`	`+ }`
	`88`	`+`
	`89`	`+每一个循环所花费的时间都不到1毫秒,除了每第五个循环会花掉大约225毫秒。像这样(单位是毫秒):`
	`90`	`+`
	`91`	`+ BBB...31744`
	`92`	`+ BBB...31744`
	`93`	`+ BBB...31744`
	`94`	`+ BBB...31744`
	`95`	`+ BBB...226365807`
	`96`	`+ BBB...31744`
	`97`	`+ BBB...31744`
	`98`	`+ BBB...31744`
	`99`	`+ BBB...31744`
	`100`	`+ BBB...226365807`
	`101`	`+ .`
	`102`	`+ .`
	`103`	`+ .`
	`104`	`+`
	`105`	`+以此类推。`
	`106`	`+`
	`107`	`+##总结:`
	`108`	`+`
	`109`	`+1. 使用Eclipse打印"B"完全没有问题`
	`110`	`+1. Netbeans有换行的问题但是可以被解决(因为在Eclipse并没有这个问题)(而不用在B后面添加空格("B "))。`
	`111`	`+`
	`112`	`+ [1]: http://en.wikipedia.org/wiki/Line_wrap_and_word_wrap`
	`113`	`+`
`64`	`114`	`stackoverflow原址:http://stackoverflow.com/questions/21947452/why-is-printing-b-dramatically-slower-than-printing`

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