java中正则表达式的应用

java.util.regex   Pattern的应用

 1 public static void main(String[] args) {
 2         //简单的正则匹配。从给定的字符串中匹配正则表达式
 3         //匹配到返回true  匹配不到返回false
 4         String regex_0 = "(\\;|\\?|\\‘|\"|%)";
 5         String s="sx?fdfs‘sd";
 6         Pattern pattern = Pattern.compile(regex_0);
 7         Matcher matcher = pattern.matcher(s);
 8         boolean as=matcher.find();//返回true 匹配到?
 9         boolean dd=matcher.find();//返回true 匹配到‘
10         boolean ss=matcher.find();//返回false 没有匹配到特殊符号
11
12
13         String regex_1=pattern.pattern();//返回当前匹配器的正则表达式  (\;|\?|\‘|"|%)
14         String string=pattern.toString();//返回 (\;|\?|\‘|"|%)
15
16         String regex_s="\\d+";
17         boolean falg=Pattern.matches(regex_s,"897");//返回 true
18
19
20         String regex_2="(\\,)";
21         String on="sxf,sxd,dong,leng";
22         Pattern pattern2=Pattern.compile(regex_2);
23         String[] ad=pattern2.split(on);//[sxf, sxd, dong, leng]
24
25         String regex_3="([0-9]+)|(\\,)";
26         String on2="sxf8sxs94sxy0df,hsl879dzq,xjt  45   ";
27         Pattern pattern3=Pattern.compile(regex_3);
28         String[] y=pattern3.split(on2);//[sxf, sxs, sxy, df, hsl, dzq, xjt  ,    ]
29         String[] x=pattern3.split(on2,3);//[sxf, sxs, sxy0df,hsl879dzq,xjt  45   ](当3>0 匹配3-1次，数组长度不大于3，数组最后一个是除匹配到的剩余的串)
30         String[] z=pattern3.split(on2,9);//[sxf, sxs, sxy, df, hsl, dzq, xjt  ,    ]
31         String[] h=pattern3.split(on2,-1);//[sxf, sxs, sxy, df, hsl, dzq, xjt  ,    ](当第二个参数<0,匹配次数不受限制，数组长度为任意长度)
32         String[] m=pattern3.split(on2,0);//[sxf, sxs, sxy, df, hsl, dzq, xjt  ,    ]
33     }