bug1 fastJson循环引用引发一个bug
fastJson可以将一个对象序列化为json,也可以通过反序列化出一个完整的对象。且支持循环引用。
package com.sincetimes.website.core.common.support;
import com.sincetimes.website.core.common.vo.ToStringAbstract;
/** ::new */
public class DataSimpleVO {
public String name;
public Object value;
public Object value1;
public DataSimpleVO() {
}
public DataSimpleVO(String name,Object value) {
this.name = name;
this.value = value;
}
@Override
public String toString() {
return "DataSimpleVO [name=" + name + ",value=" + value + ",value1=" + value1 + "]";
}
}
DataSimpleVO a = new DataSimpleVO("a",1);
DataSimpleVO b = new DataSimpleVO("b",2);
b.value = a;
Map<String,Object> map = new HashMap<>();
map.put(a.name,a);
b.value1 = map;
String jsonStr = JSON.toJSONString(b);
System.out.println(jsonStr);
DataSimpleVO obj = JSON.parSEObject(jsonStr,DataSimpleVO.class);
System.out.println(obj.toString());
执行结果
{"name":"b","value":{"name":"a","value":1},"value1":{"a":{"$ref":"$.value"}}}
DataSimpleVO [name=b,value={"name":"a",value1={"a":{"name":"a","value":1}}]
反序列化成功
改一下代码
DataSimpleVO a = new DataSimpleVO("a",2);
b.value1 = a;
Map<String,a);
b.value = map;
String jsonStr = JSON.toJSONString(b);
System.out.println(jsonStr);
DataSimpleVO obj = JSON.parSEObject(jsonStr,"value":{"a":{"name":"a","value":1}},"value1":{"$ref":"$.value.a"}}
DataSimpleVO [name=b,value={"a":{"name":"a",value1=null]
b中的value1为空,反序列化失败
bug2 要序列化的类含有Class类型属性引起的循环递归无法结束最后内存溢出
要序列化、反序列化的类
public class Request implements Serializable {
private static final long serialVersionUID = -3145939364922415428L;
private Class<?> clazz;
private String method;
private Object param;
public Class<?> getClazz() {
return clazz;
}
public void setClazz(Class<?> clazz) {
this.clazz = clazz;
}
public String getMethod() {
return method;
}
public void setMethod(String method) {
this.method = method;
}
public Object getParam() {
return param;
}
public void setParam(Object param) {
this.param = param;
}
public Object invoke(Object bean) throws Exception {
return clazz.getMethod(method,param.getClass()).invoke(bean,param);
}
}
触发bug
Request r = new Request();
r.setClazz(Integer.class);
String s = JSON.toJSONString(r,SerializerFeature.WriteClassName);
System.out.println(s);
JSON.parSEObject(s);//bug 触发
我们看看内部
public static JSONObject parSEObject(String text) {
Object obj = parse(text);
if (obj instanceof JSONObject) {
return (JSONObject) obj;
}
return (JSONObject) JSON.toJSON(obj);
}
如果改为JSON.parSEObject(s,Request.class);或者直接使用JSON.parse(str)就没问题。
最后的建议: 不要使用JSON.parSEObject(…)只使用JSON.parse(str);
原文链接:https://www.f2er.com/json/288824.html