java - 使用 json-lib 转换为 java 会抛出 ClassCastException

Question

我正在使用json-lib将 json 对象转换为 java。 代码如下:

public class JsonConvertorDemo {

    public static void main(String[] args) {
        B b1 = new B("b1");
        Map<String, B> bMap = new HashMap<String, B>();
        bMap.put("key1", b1);
        A a1 = new A(bMap);

        JSONObject jsonObject = JSONObject.fromObject(a1);
        String json = jsonObject.toString();
        jsonObject = JSONObject.fromObject(json);

        Map<String, Class> classMap = new HashMap<String, Class>();
        classMap.put("bMap", Map.class);
        a1 = (A) JSONObject.toBean(jsonObject, A.class, classMap);

        bMap = a1.getbMap();
        System.out.println(bMap.get("key1").getB1());
    }
}

public class A {
    private Map<String, B> bMap = new HashMap<String, B>();
    public A() {}
    public A(Map<String, B> bMap) {
        this.bMap = bMap;
    }
    public Map<String, B> getbMap() {
        return bMap;
    }
    public void setbMap(Map<String, B> bMap) {
        this.bMap = bMap;
    }
}

public class B {
    private String b1;
    public B() {}
    public B(String b1) {
        this.b1 = b1;
    }
    public String getB1() {
        return b1;
    }
    public void setB1(String b1) {
        this.b1 = b1;
    }
}

它抛出以下异常:

Exception in thread "main" java.lang.ClassCastException:
net.sf.ezmorph.bean.MorphDynaBean cannot be cast to code.orgexample.json.B
at code.orgexample.json.JsonConvertorDemo.main(JsonConvertorDemo.java:30)

有没有办法在 json-lib 中指定 map 值的类类型？

非常感谢您的帮助。

Answer 1

上面写着here fromObject 接受 JSON 格式的字符串、Maps、DynaBeans 和 JavaBeans