小编GAK*_*GAK的帖子

    var map1= new Map();
    map1.set("one",1);
    var map2 = new Map();
    map2.set("two",2);
   concatMap = {};
   concatMap['one']= map1;
   concatMap['two']= map2;
 JSON.stringify(concatMap);

//输出：“ {”一个“：{}，”两个“：{}}”

我也尝试过：

concatMap = {};
concatMap.one= map1;
concatMap.two= map2;

为什么在使用JSON.stringify（）时得到空对象而不是地图1和地图2？

我对 AWS ALB 的 curl 命令不起作用

    curl -v --cacert "/filepath/cert.pem" --cert "filepath/cert.pem:password" \
https://xxxxx.us-east-1.elb.amazonaws.com/xxxx/xxxx \
-H "Accept:application/json" \
-H "Content-Type:application/json" \
-H "Host:myhost.com"

给出以下错误：

 HTTP/1.1 200 Connection established
* Proxy replied OK to CONNECT request
* ALPN, offering h2
* ALPN, offering http/1.1
* Cipher selection: ALL:!EXPORT:!EXPORT40:!EXPORT56:!aNULL:!LOW:!RC4:@STRENGTH
* successfully set certificate verify locations:
*   CAfile: /filepath/cert.pem
  CApath: none
* TLSv1.2 (OUT), TLS handshake, Client hello (1):
* LibreSSL SSL_connect: SSL_ERROR_SYSCALL in connection to xxx.xxx.us-east-1.elb.amazonaws.com:443 
* stopped the pause stream!
* …

我有一个简单的用户和角色实体，具有一对多映射。一个用户具有多个角色。当我尝试保存用户实体时出现错误。我在调用持久化之前设置角色对象用户。

下面是实体的快照。

用户：

package com.petpe.ejbadmin.entity;

import java.io.Serializable;
import java.util.Date;
import java.util.Set;

import javax.annotation.Generated;
import javax.persistence.Basic;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.NamedQueries;
import javax.persistence.NamedQuery;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import javax.persistence.Temporal;
import javax.persistence.TemporalType;
import javax.validation.constraints.NotNull;
import javax.validation.constraints.Size;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlTransient;


@Entity
@Table(name = "users")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "User.findAll", query = "SELECT u FROM User u"),
    @NamedQuery(name = "User.findByUsernameandPassword", query = "SELECT u FROM User u WHERE u.username = :username AND …