Json 与 JsonNode 转换

import java.io.IOException;
import java.util.Iterator;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

public class JacksonTest {

public static void main(String[] args) throws JsonParseException, JsonMappingException, IOException {
String json = "{\"username\":\"zhangsan\",\"性别\":\"男\",\"company\":{\"companyName\":\"中华\",\"address\":\"北京\"},\"cars\":[\"奔驰\",\"宝马\"]}";
ObjectMapper mapper = new ObjectMapper();
//JSON ----> JsonNode
JsonNode rootNode = mapper.readTree(json);
Iterator<String> keys = rootNode.fieldNames();
while(keys.hasNext()){
String fieldName = keys.next();
System.out.println(fieldName + ": " + rootNode.path(fieldName).toString());
}
//JsonNode ----> JSON
System.out.println(mapper.writeValueAsString(rootNode));
}

}