如何将 JAVA 8 过滤器用于以下代码 [关闭]

Question

String url="/acct/StatsClientListService?clientType=AllClient";
List<String> urlQueryParams =new ArrayList<String>();
String clientType =null;
String urlBool = null;
List<String> urlSplit = Pattern.compile("\\?").splitAsStream(url).collect(Collectors.toList());
//condition based results
if(urlSplit.size() == 2){
    urlQueryParams=Pattern.compile("&").splitAsStream(urlSplit.get(1)).collect(Collectors.toList());
    if(urlQueryParams.size() == 2 ){
        clientType = urlQueryParams.get(0).split("=")[1];
        urlBool = urlQueryParams.get(0).split("=")[1];
        System.out.println("clientType --  "+clientType + "   urlBool ---- "+urlBool);
    }
    else{
        clientType = urlQueryParams.get(0).split("=")[1];
        System.out.println("clientType --  "+clientType);
    }
}
else{
    System.out.println("url without params");
}

Answer 1

跟随 sn-p 可能是一个起点。

URL url = new URL("http://example.com/acct/StatsClientListService"
        + "?clientType=AllClient&something=interesting");
Stream.of(url.getQuery().split("&"))
        .collect(Collectors.toMap(
                s -> s.replaceFirst("^(.*)=.*", "$1"), 
                s -> s.replaceFirst("^.*=(.*)", "$1")))
        .forEach((k, v) -> 
                System.out.printf("param: %s  value: %s%n", k, v)
        );

输出

param: clientType  value: AllClient
param: something  value: interesting

编辑如果 URL 字符串只包含路径和（可选的）查询，您可以从这个 sn-p 开始。

String urlString = "/acct/StatsClientListService"
        + "?clientType=AllClient&something=interesting";
if (urlString.contains("?")) {
    String query = urlString.substring(urlString.indexOf("?") + 1);
    Stream.of(query.split("&"))
        .collect(Collectors.toMap(
                s -> s.replaceFirst("^(.*)=.*", "$1"),
                s -> s.replaceFirst("^.*=(.*)", "$1")))
        .forEach((k, v)
                -> System.out.printf("param: %s  value: %s%n", k, v)
        );
}

输出

param: clientType  value: AllClient
param: something  value: interesting

注意需要对urlString 进行额外检查。取决于可能的值。