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Java 阵列: 识别矢量中含有常数的元素
原标题:Java Arrays: Identify elements of a vector with constants

我有一个字符串数组( String[ < < > ), 包含多个代表 XPath 查询的字符串对象。 这些查询是在设计时预先确定的。 此数组将传递给一个执行查询的对象, 然后返回一个有结果的 Map< String, ArrayList< String> & gt;


{Query that originated the result, Results vector}


ArrayList<String> firstQueryResults = xpathResults.getObject(modelQueries[0]);
... logic pertaining only to the first query results ...

以整数取回结果(在第一个查询中为“0”), 对我来说似乎并不好, 所以我想知道是否有可能通过类似 enum 的常数来辨别结果, 以便更清楚:

... = xpathResults.getObject(QueryDictionary.MODEL_PACKAGE);
... = xpathResults.getObject(QueryDictionary.COMPONENT_PACKAGE);
... = xpathResults.getObject(ModelQueries.PACKAGE);
... = xpathResults.getObject(ComponentQueries.PACKAGE);

I thought of using maps (i.e. Map<String, String> as in Map {ID, Query}) but I have still to reference the queries via an hardcoded string (e.g. "Package"). I also thought of using enums but i have several query sets (Model, Component, ...) and I also need to get all the query in a set in a String[] form in order to pass them to the object who performs the queries.


您可以使用标记界面 :

public interface QueryType {

然后您的 enums 可以执行此接口 :

public enum ModelQueries implements QueryType {

public enum ComponentQueries implements QueryType {


您的 getObject 方法可以接受类型 的参数。 您是否正在寻找类似的东西? 请告诉我如果我没有正确理解您的问题 。



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