在json字符串转java bean时，一般的对象，可以直接转，如：一个学生类，属性有姓名、年龄等

public class Student implements java.io.Serializable{    /**     * @Fields serialVersionUID : TODO    */     private static final long serialVersionUID = -1943961352036134112L;    private String sname;    private Integer age;    public String getSname() {        return sname;    }    public void setSname(String sname) {        this.sname = sname;    }    public Integer getAge() {        return age;    }    public void setAge(Integer age) {        this.age = age;    }    }

由字符串转java bean时可以使用以下方法：

JSONObject jobj = JSONObject.fromObject(str);Student s = (Student) JSONObject.tobean(jobj，Student.class);

是没有问题的，但是如果属性中含有复杂的类型，当其中属性有类似List , Map ,ArrayList、自定义的类型，如List<Teacher> teachers, 就不可以了。 会报错：MorphDynaBean cannot be cast to con.test……

在JSONObject.toBean的时候如果转换的类中有集合,可以先定义Map<String, Class> classMap = new HashMap<String, Class>();在classMap中put你要转换的类中的集合名,像:classMap.put("teachers", Teacher.class);然后在toBean()的时候把参数加上, 像:Student student=(Student) JSONObject.toBean(str, Student.class, classMap);

 

比如我定义了如下类型：

import java.util.List;/** * * 
Tiltle: AnalysisModel.java 
* 
Description:模型类  
* @author biyutong* @date Jun 11, 2012 9:37:54 AM * @version:V1.0 */public class AnalysisModel implements java.io.Serializable{    /**     * 固定条件     */    private List
     
       regularCondtionList;//    /**     * 动态条件     */    private List
      
        dynamicConFieldList;    /**     * 结果     */    private List
       
         resultField;    /**     * 获取前多少条数据     */    private Integer topnum;    /**     * 顺序还是随机     */    private String sortFlag;    /**     * 备注     */    private String remark;    /**     * 模型名称     */    private String modelName;    /**     * 对应的xml文件名称     */    private String fileName;    public List
        
          getRegularCondtionList() {        return regularCondtionList;    }    public void setRegularCondtionList(List
         
           regularCondtionList) {        this.regularCondtionList = regularCondtionList;    }    public List
          
            getDynamicConFieldList() { return dynamicConFieldList; } public void setDynamicConFieldList(List
           
             dynamicConFieldList) { this.dynamicConFieldList = dynamicConFieldList; } public Integer getTopnum() { return topnum; } public void setTopnum(Integer topnum) { this.topnum = topnum; } public String getSortFlag() { return sortFlag; } public void setSortFlag(String sortFlag) { this.sortFlag = sortFlag; } public String getRemark() { return remark; } public void setRemark(String remark) { this.remark = remark; } public String getModelName() { return modelName; } public void setModelName(String modelName) { this.modelName = modelName; } public List
            
              getResultField() { return resultField; } public void setResultField(List
             
               resultField) { this.resultField = resultField; } public String getFileName() { return fileName; } public void setFileName(String fileName) { this.fileName = fileName; } }
             
            
           
          
         
        
       
      
     

在转化的时候需要这样来写：

Map
     
       classMap = new HashMap
      
       ();classMap.put("regularCondtionList", Condition.class);classMap.put("dynamicConFieldList", ConditionField.class);classMap.put("resultField", ResultField.class);AnalysisModel analysisModel=(AnalysisModel) JSONObject.toBean(str, AnalysisModel.class, classMap);
      
     

 

from: http://biyutong.iteye.com/blog/1566708