json字符串如何转换为java对象

public static void main(String[] args) {        String json="{"+                        "'PriceProductType': '1',"+                        "'PriceRouteType': 'OW',"+                        "'PriceList': [{"+                            "'PassengerType': 'ADT',"+                            "'FareBasis': 'Y93',"+                            "'TourCode': 'EH',"+                            "'Discount': '93',"+                            "'EI': '免费更改',"+                            "'Comment': 'null',"+                            "'Baggage': '20KG',"+                            "'ValidityPeriod': 'null',"+                            "'MinStay': 'null',"+                            "'PriceValue': 1760,"+                            "'RSP': 1890,"+                            "'RefundedFlag': true,"+                            "'RefundedComment': '航班起飞前2小时（含），免费退票；航班起飞前2小时内及航班起飞后，收取10%的退票手续费（退票手续费不得低于50元）。',"+                            "'ChangedComment': '免费改期；允许签转；',"+                            "'RescheduledFlag': true,"+                            "'FreeChangeTimes': 99,"+                            "'UpgradeFlag': true,"+                            "'ChangeAirLineFlag': true,"+                            "'YPrice': 1890,"+                            "'FareID': '17292',"+                            "'YQTax': 100,"+                            "'CNTax': 50,"+                            "'CombineRuleInfo': 'null',"+                            "'FareSign': 'AD489916A9561C9757E00F2475E60CDBDD5E66C2'" +                        "}]" +                    "}";        json = json.replace("null", "1111");        System.out.println(json);        Map<String, Object> classMap = new HashMap<String, Object> ();        classMap.put( "PriceList", HOPrice.class );                        HOProductPrice bean = (HOProductPrice)JSONObject.toBean( JSONObject.fromObject(json), HOProductPrice.class, classMap);        System.out.println(bean);            }public class HOProductPrice {    public HOProductPrice() {        super();    }    private String PriceProductType = "";    private String PriceRouteType = "";    private List<HOPrice> PriceList;//set,get}public class HOPrice {    public HOPrice() {        super();    }    private String PassengerType = "";    private String FareBasis = "";    private String TourCode = "";    private String Discount = "";    private String EI = "";    //    private String Comment = "";    private String Baggage = "";    private String ValidityPeriod = "";    private String MinStay = "";    private double PriceValue = 0.0 ;    private double RSP = 0.0 ;    //    private boolean  RefundedFlag;    private String RefundedComment = "";    private String ChangedComment = "";    private boolean  RescheduledFlag;    private int FreeChangeTimes = 0 ;    private boolean ChangeAirLineFlag;    private boolean UpgradeFlag ;    private double YPrice = 0.0  ;  //    private String FareID = "";    private double YQTax = 0.0;     //    private double CNTax = 0.0;     //    private String FareSign = "";    private String CombineRuleInfo="";//set,get}

import net.sf.json.JSONObject;public class JsonTest {    public static void main(String[] args) {        String str = "{\"lendperson\":\"李四\",\"lendcompany\":\"有限公司\",\"checkperson\":\"李四\",\"lenddate\":\"2010-07-19T00:00:00\",\"lendcounts\":4,\"" +                "passports\":[{\"passportid\":\"d\",\"name\":\"李豫川\",\"passporttype\":\"K\"},{\"passportid\":\"K9051\",\"name\":\"李平\",\"passporttype\":\"K\"}," +                "{\"passportid\":\"K90517\",\"name\":\"袁寒梅\",\"passporttype\":\"K\"},{\"passportid\":\"K905199\",\"name\":\"贺明\",\"passporttype\":\"K\"}]}";                JSONObject j = JSONObject.fromObject(str);        System.out.println(j.get("lendperson"));    }}