java對象和json資料轉換實現方式3-使用jackson實現

標籤：java對象轉換json   json轉換對象   json   jackson   

測試代碼：

package com.yanek.util.json;import java.io.IOException;import java.io.StringWriter;import java.util.ArrayList;import java.util.List;import com.fasterxml.jackson.core.JsonFactory;import com.fasterxml.jackson.core.JsonGenerator;import com.fasterxml.jackson.core.JsonParseException;import com.fasterxml.jackson.databind.JsonMappingException;import com.fasterxml.jackson.databind.ObjectMapper;public class JacksonUtil {/** * @param args */public static void main(String[] args) {Hotel h1=new Hotel();h1.setId(1);h1.setName("name1");Hotel h2=new Hotel();h2.setId(2);h2.setName("name2");RoomTypeVO t1=new RoomTypeVO();t1.setPrice("20");t1.setTypeid(1);t1.setTypename("nnn1");List<RoomTypeVO> RoomTypeVOs=new ArrayList<RoomTypeVO>();RoomTypeVOs.add(t1);RoomTypeVOs.add(t1);h1.setRoomTypeVOs(RoomTypeVOs);Hotel hotel=new Hotel();try {System.out.println("json1:::"+bean2Json(h1));String s=bean2Json(h1);hotel=json2Bean(s,Hotel.class);System.out.println("json2:::"+bean2Json(hotel));System.out.println("json3:::"+bean2Json(RoomTypeVOs));String s2=bean2Json(RoomTypeVOs);List<RoomTypeVO> RoomTypeVOs2=new ArrayList<RoomTypeVO>();RoomTypeVOs2=json2Bean(s2,List.class);System.out.println("json4:::"+bean2Json(RoomTypeVOs2));} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}public static String bean2Json(Object obj) throws IOException {        ObjectMapper mapper = new ObjectMapper();        StringWriter sw = new StringWriter();        JsonGenerator gen = new JsonFactory().createJsonGenerator(sw);        mapper.writeValue(gen, obj);        gen.close();        return sw.toString();    }    public static <T> T json2Bean(String jsonStr, Class<T> objClass)            throws JsonParseException, JsonMappingException, IOException {        ObjectMapper mapper = new ObjectMapper();        return mapper.readValue(jsonStr, objClass);    }}

輸出如下：

json1:::{"id":1,"name":"name1","roomTypeVOs":[{"typeid":1,"typename":"nnn1","price":"20"},{"typeid":1,"typename":"nnn1","price":"20"}]}json2:::{"id":1,"name":"name1","roomTypeVOs":[{"typeid":1,"typename":"nnn1","price":"20"},{"typeid":1,"typename":"nnn1","price":"20"}]}json3:::[{"typeid":1,"typename":"nnn1","price":"20"},{"typeid":1,"typename":"nnn1","price":"20"}]json4:::[{"typeid":1,"typename":"nnn1","price":"20"},{"typeid":1,"typename":"nnn1","price":"20"}]

相關實體類：

package com.yanek.util.json;import java.util.List;public class Hotel {public List<RoomTypeVO> getRoomTypeVOs() {return RoomTypeVOs;}public void setRoomTypeVOs(List<RoomTypeVO> roomTypeVOs) {RoomTypeVOs = roomTypeVOs;}private List<RoomTypeVO> RoomTypeVOs;public int getId() {return id;}public void setId(int id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}private int id;private String name;}package com.yanek.util.json;public class RoomTypeVO {public int getTypeid() {return typeid;}public void setTypeid(int typeid) {this.typeid = typeid;}public String getTypename() {return typename;}public void setTypename(String typename) {this.typename = typename;}public String getPrice() {return price;}public void setPrice(String price) {this.price = price;}private int typeid;private String typename;private String price;}