net.sf.ezmorph.bean.MorphDynaBean cannot be cast to

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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
但是如果存在List集合就会出新net.sf.ezmorph.bean.MorphDynaBean cannot be cast to 错误。
解决方法：

public class Student implements java.io.Serializable{
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/**
* @Fields serialVersionUID : TODO3 Z/ M2 Z) }# S. ?, G. w
*/
private static final long serialVersionUID = -1943961352036134112L;: ?" M+ P3 F7 s a& I! j
private String sname;
private Integer age;
public String getSname() {# a9 |& C$ T4 o6 e
return sname;: [- e% L s" o. f% K" M; g4 R
}
public void setSname(String sname) {
this.sname = sname;
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public Integer getAge() {
return age;
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public void setAge(Integer age) {
this.age = age;
}
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}

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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);

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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;% T$ O3 t2 ]1 m4 j1 n
/**' k* J2 D0 c# T' T3 J
*
* <P>Tiltle: AnalysisModel.java </P>
* <P>Description:模型类 </P>
* @author biyutong i) x7 Q7 T% b: }
* @date Jun 11, 2012 9:37:54 AM . L" v2 j" d# X$ A$ D
* @version:V1.0
*/. F; q- w; J( a% p* O! k
public class AnalysisModel implements java.io.Serializable{
% ?$ m4 U9 }+ Z* \0 B! ^6 Q
/**
* 固定条件 p/ a/ r9 j) h3 \0 B5 w5 S
*/' w& s c! L7 g3 c7 \
private List<Condition> regularCondtionList;//- j L9 m6 W2 H/ [6 Z) v6 V
/**$ @# A1 e) ?* \) x
* 动态条件 T5 H% p2 H) J m& E
*/
private List<ConditionField> dynamicConFieldList;
/**
* 结果
*/
private List<ResultField> resultField;- u5 A- ?$ J6 T
/**# l) `) B, s3 k2 U" p3 d3 g) q
* 获取前多少条数据
*/
private Integer topnum;
/**2 C8 F8 g$ D# W, U9 _
* 顺序还是随机
*/. J& F: o$ z; T6 Z X u4 L: J- U; x
private String sortFlag;
/**% o# c+ C; ~6 s: u' ~
* 备注
*/
private String remark;6 Z5 |) h/ X P) o5 f; |
/**
* 模型名称# ?# d9 ^2 O8 g9 N2 H& a
*/
private String modelName;4 O8 d* ^# Z( s
/**
* 对应的xml文件名称
*/% u& p0 p9 p+ l5 q+ L: u6 m: D3 o9 I
private String fileName;- m: `" g1 `5 c9 _7 `; {
public List<Condition> getRegularCondtionList() {
return regularCondtionList;5 v5 L* u' Z; \0 E1 l% X
}
public void setRegularCondtionList(List<Condition> regularCondtionList) {
this.regularCondtionList = regularCondtionList;3 u; m$ L( w3 n
}
public List<ConditionField> getDynamicConFieldList() {
return dynamicConFieldList;
}
public void setDynamicConFieldList(List<ConditionField> dynamicConFieldList) {) r7 W+ j }) v" [
this.dynamicConFieldList = dynamicConFieldList;
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public Integer getTopnum() {' c+ ~% ?" J6 i1 c2 Q# l6 q
return topnum;2 Y0 a$ a* C8 k% ~6 @
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public void setTopnum(Integer topnum) {
this.topnum = topnum;
}
public String getSortFlag() {: k' B: _ F2 b: V
return sortFlag;. {" J+ n2 A6 J
}5 }. C D3 _* L3 ? D. F1 E
public void setSortFlag(String sortFlag) {
this.sortFlag = sortFlag;4 B" k# x6 t: l$ G1 E% e) d3 x7 U
} E. T2 R" J. }3 X- t
public String getRemark() {
return remark;8 M. |/ N; { n% b" r
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public void setRemark(String remark) {4 q" X) z+ T0 l* r" ?- B4 z
this.remark = remark;3 k& b( R; R5 c% M6 {4 P
}
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public String getModelName() { D T8 y2 p: U* t7 d4 U. A! V, o; e
return modelName;
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public void setModelName(String modelName) {) c, _- R' S2 k- c4 T% _
this.modelName = modelName;
}, |. y" r5 \2 V9 Z8 `' a* D/ D* I
public List<ResultField> getResultField() {/ g* b) E8 R! w e& s
return resultField;7 }3 i. g; A, U+ d; j
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public void setResultField(List<ResultField> resultField) {
this.resultField = resultField;! o' ?9 z2 {, E
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public String getFileName() {$ q( ^3 @$ x3 ^! F# H: H4 R( ^
return fileName;/ [9 N, H6 o1 n6 w. K0 v
}
public void setFileName(String fileName) {
this.fileName = fileName;2 W: w$ H6 h$ `# U
}
}

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在转化的时候需要这样来写：

Map<String, Class> classMap = new HashMap<String, Class>();/ w1 c6 K3 C8 Z
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classMap.put("regularCondtionList", Condition.class);
classMap.put("dynamicConFieldList", ConditionField.class);
classMap.put("resultField", ResultField.class);
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AnalysisModel analysisModel=(AnalysisModel) JSONObject.toBean(str, AnalysisModel.class, classMap);

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