你可以使用XStream——它真的很方便。请看这里的例子

package com.thoughtworks.xstream.json.test;

import com.thoughtworks.xstream.XStream;
import com.thoughtworks.xstream.io.json.JettisonMappedXmlDriver;

public class WriteTest {

    public static void main(String[] args) {

      HashMap<String,String> map = new HashMap<String,String>();
      map.add("1", "a");
      map.add("2", "b");
      XStream xstream = new XStream(new JettisonMappedXmlDriver());

      System.out.println(xstream.toXML(map));       

    }

}

您可以使用Jackson将Map转换为JSON，如下所示:

Map<String,Object> map = new HashMap<>();
//You can convert any Object.
String[] value1 = new String[] { "value11", "value12", "value13" };
String[] value2 = new String[] { "value21", "value22", "value23" };
map.put("key1", value1);
map.put("key2", value2);
map.put("key3","string1");
map.put("key4","string2");

String json = new ObjectMapper().writeValueAsString(map);
System.out.println(json);

Jackson的Maven依赖:

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.5.3</version>
    <scope>compile</scope>
</dependency>

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.5.3</version>
    <scope>compile</scope>
</dependency>

If you are using `JSONObject` library, you can convert map to `JSON` as follows: JSONObject Library: import org.json.JSONObject; Map<String, Object> map = new HashMap<>(); // Convert a map having list of values. String[] value1 = new String[] { "value11", "value12", "value13" }; String[] value2 = new String[] { "value21", "value22", "value23" }; map.put("key1", value1); map.put("key2", value2); JSONObject json = new JSONObject(map); System.out.println(json); Maven Dependencies for `JSONObject` : <dependency> <groupId>org.json</groupId> <artifactId>json</artifactId> <version>20140107</version> </dependency> Hope this will help. Happy coding.

你可以使用:

new JSONObject(map);

其他函数可以从它的文档中获得 http://stleary.github.io/JSON-java/index.html

如果您正在使用JSR 374:用于JSON处理的Java API (javax JSON) 这似乎很管用:

    JsonObjectBuilder job = Json.createObjectBuilder((Map<String, Object>) obj);
    JsonObject jsonObject = job.build();

这通常是Json库的工作，你不应该尝试自己做。所有json库都应该实现您所要求的内容，而且您可以做到 在页面底部的json.org上找到Java Json库的列表。

我找到了另一种处理方法。

Map obj=new HashMap();    
obj.put("name","sonoo");    
obj.put("age",new Integer(27));    
obj.put("salary",new Double(600000));   
String jsonText = JSONValue.toJSONString(obj);  
System.out.print(jsonText);

希望这能有所帮助。

谢谢。