Java正则-String.matches的坑 版本 java8

今天在处理一个正则匹配时，使用原来的方式写好正则表达式，在正则表达式在线测试网站测试正常；

放在测试用例中始终都时false；

String agent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36";

System.out.println("agent:"+agent.matches("/Mozilla|AppleWebKit|Chrome/i"));

网上一通查找，发现此文章 说正则表达式会在前后添加 ^$ 进行匹配，修改测试代码片段测试基本符合 

String agent = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.106 Safari/537.36";

System.out.println("agent:"+agent.matches("/Mozilla|AppleWebKit|Chrome/i"));  //false     System.out.println("agent2:"+Pattern.compile("Mozilla|AppleWebKit|Chrome").matcher(agent).matches());//false
System.out.println("agent2:"+agent.matches(".*[Mozilla|AppleWebKit|Chrome].*")); //true

随手打开Java8 的Pattern 源码，发现在javadoc中已经说明了匹配的方式

//Pattern.matches() 
public static boolean matches(String regex, CharSequence input) {
        Pattern p = Pattern.compile(regex);
        Matcher m = p.matcher(input);
        return m.matches();
    }




Matcher.matches()

/**
     * Attempts to match the entire region against the pattern.
     *
     * 
 If the match succeeds then more information can be obtained via the
     * start, end, and group methods.  
     *
     * @return  true if, and only if, the entire region sequence
     *          matches this matcher's pattern
     */
    public boolean matches() {
        return match(from, ENDANCHOR);
    }

仅在整个输入串匹配正则表达式的时候返回 true；