// 按指定模式在字符串查找
String line = "This order was placed for QT3000! OK?";
String pattern = "(\\D*)(\\d+)(.*)";
// 创建 Pattern 对象
Pattern r = Pattern.compile(pattern);
// 现在创建 matcher 对象
Matcher m = r.matcher(line);
找到所有匹配到的子串
String exp = "(.*?)\\((.*?)\\),";
Pattern pattern = Pattern.compile(exp);
String a = "Mary(12),Tom(20),Jhon(32),";
Matcher matcher = pattern.matcher(a);
while (matcher.find()) {
// 打印子串中的所有内容：0是完整子串。n要取等
int n = matcher.groupCount();
System.out.print(n);
for (int i = 0; i <= n; i++) {
System.out.print(" " + matcher.group(i));
}
System.out.println();
}
group()方法如果里面填写的是数字，那么返回的就是括号里面的内容
如果里面是名字，那么返回的就是尖括号里面的内容
所以，以数字取本质上和用名字取是一样的
java 获取正则表达式自身里面的变量
private static String[] getAllExpName(String exp) {
String reg = "<(\\w+)>";
Pattern pattern = Pattern.compile(reg);
Matcher matcher = pattern.matcher(exp);
String[] ans = new String[];
int cnt = 0;
while (matcher.find()){
ans[cnt++] = matcher.group();
}
return ans;
}
