我试图去通过串并更换正则表达式匹配字符串的所有实例。 出于某种原因,当我使用if
然后它会工作,并更换正则表达式匹配的只是一个字符串实例。 当我改变了if
到while
则它在本身的一些奇怪的更换,使得第一正则表达式匹配字符串的一塌糊涂,而即使不触及其他...
pattern = Pattern.compile(regex);
matcher = pattern.matcher(docToProcess);
while (matcher.find()) {
start = matcher.start();
end = matcher.end();
match = docToProcess.substring(start, end);
stringBuilder.replace(start, end, createRef(match));
docToProcess = stringBuilder.toString();
}
除了从sysouts我只加了最后的分配。 看看是否有帮助:
// your snippet:
pattern = Pattern.compile(regex);
matcher = pattern.matcher(docToProcess);
while (matcher.find()) {
start = matcher.start();
end = matcher.end();
match = docToProcess.substring(start, end);
String rep = createRef(match);
stringBuilder.replace(start, end, rep);
docToProcess = stringBuilder.toString();
// my addition:
System.out.println("Found: '" + matcher.group() + "'");
System.out.println("Replacing with: '" + rep + "'");
System.out.println(" --> " + docToProcess);
matcher = pattern.matcher(docToProcess);
}
不知道到底你得到了什么问题,但也许这个例子有点帮助:
我想在这样的句子来更改名称:
- 杰克 - >阿尔伯特
- 阿尔伯特 - >保罗
- 保罗 - >杰克
我们可以用一点帮助做到这一点appendReplacement和appendTail从方法Matcher
类
//this method can use Map<String,String>, or maybe even be replaced with Map.get(key)
static String getReplacement(String name) {
if ("Jack".equals(name))
return "Albert";
else if ("Albert".equals(name))
return "Paul";
else
return "Jack";
}
public static void main(String[] args) {
String sentence = "Jack and Albert are goint to see Paul. Jack is tall, " +
"Albert small and Paul is not in home.";
Matcher m = Pattern.compile("Jack|Albert|Paul").matcher(sentence);
StringBuffer sb = new StringBuffer();
while (m.find()) {
m.appendReplacement(sb, getReplacement(m.group()));
}
m.appendTail(sb);
System.out.println(sb);
}
输出:
Albert and Paul are goint to see Jack. Albert is tall, Paul small and Jack is not in home.
如果createRef(匹配)返回一个字符串这是不相同的长度(结束 - 开始),则使用的是在docToProcess.substring(开始,结束)的索引将潜在地重叠。