Java 尝试使用 String.split("\\?") 时的意外行为
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Unexpected behaviour when trying to use String.split("\\?")
提问by fredcrs
So I have a string that is like this:
所以我有一个像这样的字符串：
"Some text here?Some number here"
and I need to split those, I am using String.split("\\?"), but if I have a string like this:
我需要拆分这些，我正在使用String.split("\\?")，但如果我有这样的字符串：
"This is a string with, comma?1234567"
I have it splitted in the comma(,) too. And if I have this String:
我也把它用逗号（,）分开了。如果我有这个字符串：
"That′s a problem here?123456"
It also splits on ′, So how can I fix this?
它也分裂了′，那么我该如何解决这个问题呢？
采纳答案by Richard H
I am not seeing this behaviour: (nor would I expect to)
我没有看到这种行为：（我也不希望看到）
String s ="hello?1000";
String[] fields = s.split("\?");
for (String field : fields) {
System.out.println(field);
}
yields:
产量：
hello
你好
1000
1000
Introducing a comma "," or an apostrophe "'" doesn't make any difference to the split:
引入逗号“,”或撇号“'”对拆分没有任何影响：
String s ="he,llo?1000";
yields:
产量：
he,llo
你好
1000
1000
String s ="he'llo?1000";
yields:
产量：
he'llo
你好
1000
1000
The spilt also works fine if you have any spaces in your input string. I can only suggest that your regex is not what you think it is!
如果输入字符串中有任何空格，溢出也可以正常工作。我只能建议您的正则表达式不是您认为的那样！
回答by michel.iamit
Looks like a typical regex problem. I am using this for example to split
看起来像一个典型的正则表达式问题。例如，我正在使用它来拆分
name (code)
into a pair with the name and the code separate:
成对，名称和代码分开：
RE regex = new RE("(.*) \W(.*)\W");
if(!regex.match(term)){
throw new InvalidArgumentException("the given term does not match the regelar expression:'NAME (ID)'");
}
Pair<String,String> pair=new Pair<String,String>(regex.getParen(1),regex.getParen(2));
return pair;
回答by michel.iamit
this is the solution: (EDIT: it's even simpler)
这是解决方案：（编辑：它更简单）
public static Pair<String,String> getSplittedByQuestionMark(String term){
String[] list=term.split("[?]");
return new Pair<String,String>(list[0],list[1]);
}
i tested it:
我测试了它：
@Test
public void testGetSplittedByQuestionMark(){
ArrayList<String> terms=new ArrayList<String>();
ArrayList<Pair<String,String>> expected=new ArrayList<Pair<String,String>>();
terms.add("test?a");
terms.add("test?20");
terms.add("test, with comma?ab10");
expected.add(new Pair<String,String>("test","a"));
expected.add(new Pair<String,String>("test","20"));
expected.add(new Pair<String,String>("test, with comma","ab10"));
for(int i=0;i<terms.size();i++){
Pair<String,String> answer = StringStandardRegex.getSplittedByQuestionMark(terms.get(i));
assertTrue("answer="+answer.getFirst(),answer.getFirst().equals(expected.get(i).getFirst()));
assertTrue("answer="+answer.getSecond(),answer.getSecond().equals(expected.get(i).getSecond()));
}
}
[EDIT after remark below] I have added a test, Now I don;t see what's the problem, this works as well (and is even more simpel):
[在下面评论后编辑]我添加了一个测试，现在我不知道有什么问题，这也有效（甚至更简单）：
@Test
public void testGetSplittedByQuestionMarkNotUsingRegex(){
ArrayList<String> terms=new ArrayList<String>();
ArrayList<Pair<String,String>> expected=new ArrayList<Pair<String,String>>();
terms.add("test?a");
terms.add("test?20");
terms.add("test, with comma?ab10");
expected.add(new Pair<String,String>("test","a"));
expected.add(new Pair<String,String>("test","20"));
expected.add(new Pair<String,String>("test, with comma","ab10"));
for(int i=0;i<terms.size();i++){
String[] answer=terms.get(i).split("\?");
assertTrue("answer="+answer[0],answer[0].equals(expected.get(i).getFirst()));
assertTrue("answer="+answer[1],answer[1].equals(expected.get(i).getSecond()));
}
}
