表示取出"EventType":" 到 "之间的字符串，非贪婪匹配

(?<="EventType":").*?(?=")

如果后面"也换成字符串的话，就把?=换成?<=即可

例子如下：

    public String getPattern(String str,String pattern){
        Pattern compile = Pattern.compile("(?<=\""+pattern+"\":\").*?(?=\")", Pattern.CASE_INSENSITIVE);
        Matcher matcher = compile.matcher(str);
        boolean b = matcher.find();
        if (b){
            return matcher.group(0);
        }else {
            return "";
        }
    }

    public static void main(String[] args) {
        String str = "{\"Header\":{\"DcdGuid\":\"${#DCDGuid}\",\"DevGuid\":\"${#DevGuid}\",\"Sid\":\"${#Sid}\",\"Timestamp\":\"${#Timestamp}\"},\"Data\":{\"AppName\":\"\",\"EventType\":\"LoginOper\",\"FunClassTag\":\"Login\",\"FunClassValue\":\"failure\",\"DiscoverTime\":\"${#RealTime}\",\"Details\":{\"LoginType\":\"-\",\"LoginSourceIp\":\"${1.3.6.1.4.1.2011.5.25.207.1.2.1.1.2.34}\",\"User\":\"${1.3.6.1.4.1.2011.5.25.207.1.2.1.1.4.34}\",\"Password\":\"-\"}}}";
        test test = new test();
        String eventType = test.getPattern(str,"EventType");
        String funClassTag = test.getPattern(str,"FunClassTag");
        String funClassValue = test.getPattern(str,"FunClassValue");
        System.out.println(eventType);
        System.out.println(funClassTag);
        System.out.println(funClassValue);
    }