Java 正则表达式

java.util.regex.Patternjava.util.regex.Matcher

1.Match

match 是从字符串最头部开始匹配，一直到结束，需要匹配整个串

String content = "Welcome, bob!";content.match("bob");    //falsecontent.match(".*bob")   //falsecontent.match(".*bob.*") //trueString str="test@yahoo.com.cn";Pattern pattern = Pattern.compile("[\\w\\.\\-]+@([\\w\\-]+\\.)+[\\w\\-]+",Pattern.CASE_INSENSITIVE);Matcher matcher = pattern.matcher(str);boolean a = matcher.matches(); //匹配的时候返回true

2.Find

boolean b = matcher.find(); //包含正则匹配的串为true// 找到所有匹配的串while(matcher.find()) {    String extracted = matcher.group(0)}

3.Replace

matcher.replaceFirst("")matcher.replaceAll("");

4.Group

group(0) 代表整个表达式String line = "#星座运势#20171013";String pattern = "\\#(\\p{L}*)\\#(\\d+)";  //\p{L}  匹配 unicode any kind of letter from any language// 创建 Pattern 对象Pattern r = Pattern.compile(pattern); // 现在创建 matcher 对象Matcher m = r.matcher(line);if (m.find( )) {   System.out.println("Found value: " + m.group(0) );    // "#星座运势#20171013"   System.out.println("Found value: " + m.group(1) );    // 星座运势   System.out.println("Found value: " + m.group(2) );    // 20171013} else {   System.out.println("NO MATCH");}