关于Java：Java——从文字值对实例化一个哈希图

Java - instantiate a hashmap from literal value pairs

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我想用Java中的文字实例化Java哈希映射。我使用的是Java 8。

我从Java书中的函数编程中看到，你可以用列表来完成：

1	final List<String> cities = Arrays.asList("Albany","Boulder","Chicago","Denver","Eugene");

但是我还没有看到如何用散列图做类似的事情。

我可以这样创建散列图：

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import java.util.HashMap;
import java.util.Map;

public class ShortestPath1 {
public static void main(final String[] args) {
final Map<String,Integer> station2nlc = new HashMap<String, Integer>();
station2nlc.put("Ealing Broadway", 319000);
station2nlc.put("Ealing Common", 319005);
station2nlc.put("Acton Town LT", 50000);
station2nlc.put("Chiswick Park LT", 54500);
station2nlc.put("Turnham Green LT", 73400);
station2nlc.put("Stamford Brook LT", 71300);
station2nlc.put("Ravenscourt Park LT", 68200);
station2nlc.put("Hammersmith LT", 59300);
station2nlc.put("Barons Court LT", 51600);
station2nlc.put("West Kensington", 76000);
station2nlc.put("Earls Court LT", 56200);
station2nlc.put("West Kensington LT", 76000);

System.out.println("Ealing has NLC:" + station2nlc.get("Ealing Broadway"));
}
}

但是这种语法意味着Java正在构建每行指令的HASMAP。可能是这样。

为了比较，C++中的例子是我认为可能的：

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#include <string>
#include <unordered_map>
#include <iostream>

int main() {
std::unordered_map<std::string, int> station2nlc(
{
{"Ealing Broadway", 319000 },
{"Ealing Common", 319005 },
{"Acton Town LT", 50000 },
{"Chiswick Park LT", 54500 },
{"Turnham Green LT", 73400 },
{"Stamford Brook LT", 71300 },
{"Ravenscourt Park LT", 68200 },
{"Hammersmith LT", 59300 },
{"Barons Court LT", 51600 },
{"West Kensington", 76000 },
{"Earls Court LT", 56200 },
{"West Kensington LT", 76000 },
});

std::cout <<"Ealing has NLC:" << station2nlc["Ealing Broadway"] << std::endl;
}