JAVA中使用正则表达式的若干方法.docx

JAVA中使用正则表达式的若干方法正则的具体写法不是重点，一般常用的还是比较简单的主要想说的是在JAVA里使用正则的几种情况先来定义两个变量：?1、被查找的字符串：str2、要查找的关键字（或正则表达式）：keywordPattern?情况一：判断str里是否含有keywordPattern??1?import?java.util.regex.Matcher;?2?import?java.util.regex.Pattern;?3??4?public?class?RegTest?{?5?????public?static?void?main(String[]?args)?{?6?????????String?str?=?我是人。。我是好人。。我是好男人。。-?-?!!;?7?????????Pattern?keywordPattern?=?Ppile(好男人);?8?????????Matcher?matcher?=?keywordPattern.matcher(str);?9?????????System.out.println(str.find());10?????}11?}输出：true?情况二：判断str是否完全符合keywordPattern，可用于邮箱验证等情况??1?public?class?RegTest?{?2?????public?static?void?main(String[]?args)?{?3?????????String?str?=?abcd1234ABCD;?4?????????Pattern?keywordPattern?=?Ppile(^[a-zA-Z0-9]+$);?5?????????Matcher?matcher?=?keywordPattern.matcher(str);?6??7?????????System.out.println(matcher.matches());?8?????????//System.out.println(matcher.find());?也可以实现同样的效果?9?????}10?}输出：true?情况三：将str中符合keywordPattern的字符都替换掉??1?import?java.util.regex.Matcher;?2?import?java.util.regex.Pattern;?3??4?public?class?RegTest?{?5?????public?static?void?main(String[]?args)?{?6?????????String?str?=?abcd1234ABCD;?7?????????Pattern?keywordPattern?=?Ppile([0-9]);?8?????????Matcher?matcher?=?keywordPattern.matcher(str);?9?10?????????System.out.println(matcher.replaceAll(@));11?????}12?}?输出：abcd@@@@ABCD情况四：将str中符合keywordPattern的字符替换掉一部分，某些被替换的字符还需保留???1?import?java.util.regex.Matcher;?2?import?java.util.regex.Pattern;?3??4?public?class?RegTest?{?5?????public?static?void?main(String[]?args)?{?6?????????String?str?=?12[3]456[7]890;?7?????????Pattern?keywordPattern?=?Ppile(\\[(\\d)\\]);?8?????????Matcher?matcher?=?keywordPattern.matcher(str);?9?10?????????System.out.println(matcher.replaceAll($1));11?????}12?}?输出：1234567890?情况五：将str中符合keywordPattern的字符替换掉一部分，某些被替换的字符还需做为参数进行处理??1?import?java.util.regex.Matcher;????2?import?java.util.regex.Pattern;????3????4?public?class?RegTest?{????5?????public?static?void?main(String[]?args)?{????6?????????String?str?=?a[b]cdef[g]hij[k]lmn;????7????????