java 如何将 hashMap 转换为 Json 文件
声明：本页面是StackOverFlow热门问题的中英对照翻译，遵循CC BY-SA 4.0协议，如果您需要使用它，必须同样遵循CC BY-SA许可，注明原文地址和作者信息，同时你必须将它归于原作者（不是我）：StackOverFlow
原文地址: http://stackoverflow.com/questions/11851603/
Warning: these are provided under cc-by-sa 4.0 license. You are free to use/share it, But you must attribute it to the original authors (not me):
StackOverFlow
how to convert hashMap to Json file
提问by NewCodeLearner
I am leaning Java.
我正在学习 Java。
I have to transfer a Hashmap to Server using rpc.
我必须使用 rpc 将 Hashmap 传输到服务器。
HashMap
哈希表
Map<String, String> testMap = new HashMap<String, String>();
testMap .put("1", "abc");
testMap .put("2", "ezc");
testMap .put("3", "afc");
testMap .put("4", "cvc");
..
how to do that.
怎么做。
采纳答案by Prso
See this link if its helps..
如果有帮助，请参阅此链接。
http://www.mkyong.com/java/how-to-convert-java-map-to-from-json-Hymanson/
http://www.mkyong.com/java/how-to-convert-java-map-to-from-json-Hymanson/
import com.fasterxml.Hymanson.databind.ObjectMapper;
ObjectMapper mapper = new ObjectMapper();
Map<String, String> testMap = new HashMap<String, String>();
testMap .put("1", "abc");
testMap .put("2", "ezc");
testMap .put("3", "afc");
testMap .put("4", "cvc");
mapper.writeValue(new File("c:\user.json"), testMap);
回答by Steve Kuo
Take a look at Hymanson JSON processor. In particular the code will look something like:
看看Hymanson JSON 处理器。特别是代码看起来像：
Map map = your map
ObjectMapper mapper = new ObjectMapper();
String json = mapper.writeValueAsString(map);
If you want pretty JSON (multiple lines) for debugging, then use:
如果您想要漂亮的 JSON（多行）进行调试，请使用：
String json = mapper.defaultPrettyPrintingWriter().writeValueAsString(map);
回答by Byter
you can also try GSONlibrary. It is fast and easy to use.
The Below wrapper class will make your job even more easy
你也可以试试GSON图书馆。它快速且易于使用。下面的包装类将使您的工作更加轻松
public class ConvertJsonToObject {
private static Gson gson = new GsonBuilder().create();
public static final <T> T getFromJSON(String json, Class<T> clazz) {
return gson.fromJson(json, clazz);
}
public static final <T> String toJSON(T clazz) {
return gson.toJson(clazz);
}
}
All you need to do is
你需要做的就是
Map<String, String> testMap = new HashMap<String, String>();
testMap .put("1", "abc");
testMap .put("2", "ezc");
testMap .put("3", "afc");
testMap .put("4", "cvc");
String json = ConvertJsonToObject.toJSON(testMap);
and you can easily get your original Objectback on the other side
你可以很容易地original Object回到other side
Map<String, String> newTestMap = ConvertJsonToObject.getFromJSON(json,Map.class);
回答by Alain BUFERNE
I don't catch : HashMap is Serializable so should be able to be used between client and server?
我不明白：HashMap 是可序列化的，所以应该能够在客户端和服务器之间使用？
