1、String.split()String有个方法是分割字符串 .split()。但是有写字符串是需要转义才能分割，不然就会出错。需要转义的字符串：. $ | ( ) [ { ^ ? * + \ 共12个特殊字符，遇到以这些字符进行分割字符串的时候，需要在这些特殊字符前加双反斜杠 \例如：str.split("\.") str.split("\$") str.split("\|") str.split("\(") str.split("\)") str.split("\[")str.split("\{") str.split("\^") str.split("\?") str.split("\*") str.split("\+")str.split("\\")
2、源码：
public String[] split(String regex) {
return split(regex, 0);
}
public String[] split(String regex, int limit) {
/* fastpath if the regex is a
(1)one-char String and this character is not one of the
RegEx's meta characters ".$|()[{^?*+\\", or
(2)two-char String and the first char is the backslash and
the second is not the ascii digit or ascii letter.
*/
char ch = 0;
if (((regex.value.length == 1 &&
".$|()[{^?*+\\".indexOf(ch = regex.charAt(0)) == -1) ||
(regex.length() == 2 &&
regex.charAt(0) == '\\' &&
(((ch = regex.charAt(1))-'0')|('9'-ch)) < 0 &&
((ch-'a')|('z'-ch)) < 0 &&
((ch-'A')|('Z'-ch)) < 0)) &&
(ch < Character.MIN_HIGH_SURROGATE ||
ch > Character.MAX_LOW_SURROGATE))
{
int off = 0;
int next = 0;
boolean limited = limit > 0;
ArrayList<String> list = new ArrayList<>();
while ((next = indexOf(ch, off)) != -1) {
if (!limited || list.size() < limit - 1) {
list.add(substring(off, next));
off = next + 1;
} else { // last one
//assert (list.size() == limit - 1);
list.add(substring(off, value.length));
off = value.length;
break;
}
}
// If no match was found, return this
if (off == 0)
return new String[]{this};
// Add remaining segment
if (!limited || list.size() < limit)
list.add(substring(off, value.length));
// Construct result
int resultSize = list.size();
if (limit == 0)
while (resultSize > 0 && list.get(resultSize - 1).length() == 0)
resultSize--;
String[] result = new String[resultSize];
return list.subList(0, resultSize).toArray(result);
}
return Pattern.compile(regex).split(this, limit);
}
【1】单个符号作为分隔符
String address=”上海|上海市|闵行区|吴中路”;
String[] splitAddress=address.split(“\|”);
//如果以竖线为分隔符，则split的时候需要加上两个斜杠【\】进行转义
System.out.println(splitAddress[0]+splitAddress[1]+splitAddress[2]+splitAddress[3]);
String address=”上海上海市闵行区吴中路”;
String[] splitAddress=address.split(“\”);
System.out.println(splitAddress[0]+splitAddress[1]+splitAddress[2]+splitAddress[3]); String address=”上海:上海市:闵行区:吴中路”;
String[] splitAddress=address.split(“\:”);
System.out.println(splitAddress[0]+splitAddress[1]+splitAddress[2]+splitAddress[3]);
String address=”上海.上海市.闵行区.吴中路”;
String[] splitAddress=address.split(“\.”);
System.out.println(splitAddress[0]+splitAddress[1]+splitAddress[2]+splitAddress[3]);
String address=”上海上海市闵行区^吴中路”;
String[] splitAddress=address.split(“\^”);
System.out.println(splitAddress[0]+splitAddress[1]+splitAddress[2]+splitAddress[3]);
String address=”上海@上海市@闵行区@吴中路”;
String[] splitAddress=address.split(“@”);
System.out.println(splitAddress[0]+splitAddress[1]+splitAddress[2]+splitAddress[3]);
String address=”上海,上海市,闵行区,吴中路”;
String[] splitAddress=address.split(“,”);
System.out.println(splitAddress[0]+splitAddress[1]+splitAddress[2]+splitAddress[3]);
【2】多个符号作为分隔符
String address=”上海^上海市@闵行区#吴中路”;
String[] splitAddress=address.split(“\^|@|#”);
System.out.println(splitAddress[0]+splitAddress[1]+splitAddress[2]+splitAddress[3]);
格式小提示************************
String address = new
String(“192.168.13.240”);
String[] str = address.split(“\.”);
for(String s : str){
System.out.println(s);
}
输出格式：
192
168
13
240
System.out.println(splitAddress[0]+splitAddress[1]+splitAddress[2]+splitAddress[3]);
输出格式：上海上海市闵行区吴中路
总结：
（1）split表达式，其实就是一个正则表达式。* ^ |等符号在正则表达式中属于一种有特殊含义的字符，如果使用此种字符作为分隔符，必须使用转义符即\加以转义。
（2）如果使用多个分隔符则需要借助 |符号，如【2】所示，但需要转义符的仍然要加上分隔符进行处理。
本文来自 菜鸟Q_Q 的CSDN 博客 ，全文地址请点击：https://blog.csdn.net/qq_35812160/article/details/78604034?utm_source=copy
yanweihpu 的CSDN 博客 ，全文地址请点击：https://blog.csdn.net/yanweihpu/article/details/80499626?utm_source=copy