function Parent(parentName){
this.name = parentName;
}
Parent.prototype.printName = function(){
console.log(this.name);
}
var p = new Parent("Parent");
console.log(p);
function Child(parentName, childName){
Parent.call(this, parentName);
this.name = childName;
}
1. Child.prototype = Object.create(Parent.prototype);
2. Child.prototype = Parent.prototype;
var c = new Child("Parent","Child");
console.log(c);
有人可以告诉我上面的语句1和2之间的区别吗。无论哪种方式，子对象都可以调用c.printName（）;。
芹菜.py
from __future__ import absolute_import, unicode_literals
import os
from celery import Celery
from django.conf import settings
os.environ.setdefault('DJANGO_SETTINGS_MODULE', 'TwitterApiProxy.settings')
app = Celery('TwitterApiProxy')
app.config_from_object('django.conf:settings', namespace='CELERY')
app.autodiscover_tasks(lambda: settings.INSTALLED_APPS)
@app.on_after_configure.connect
def setup_periodic_tasks(sender, **kwargs):
# Calls test('hello') every 10 seconds.
sender.add_periodic_task(10.0, hello_test.s('hello'), name='add every 10')
@app.task
def hello_test(arg):
print(arg)
设置.py
CELERY_BROKER_URL = 'redis://localhost:6379'
CELERY_RESULT_BACKEND = 'redis://localhost:6379'
CELERY_ACCEPT_CONTENT = ['application/json']
CELERY_TASK_SERIALIZER = 'json'
CELERY_RESULT_SERIALIZER = 'json'
CELERY_TIMEZONE = 'America/Los_Angeles'
我想每 10 秒打印一次“你好”。所以celery -A TwitterApiProxy beat在我的终端中运行时，我看到如下：
LocalTime -> 2018-04-06 23:27:09
Configuration ->
. broker -> …我用pyenv安装了特定版本的python。pyenv version在终端输入时，我看到了3.5.0 (set by /Users/lcherukuri/.python-version)。但是当我打字的时候python3我得到了python3 command not found。如何解决这个问题？找不到pip3
用户.java
public class User implements Serializable{
@Id
@Size(min=5,max=15)
@Column(name="username", unique=true)
private String username;
@OneToMany(mappedBy="user")
private Collection<Role> roles;
public User(User user) {
this.username=user.username;
this.roles=user.getRoles();
}
}
角色.java
public class Role implements Serializable{
@Id
@GeneratedValue(strategy=GenerationType.AUTO)
private int id;
private String role;
@ManyToOne
@JoinColumn(name="username")
private User user;
}
UserServiceImpl.java
public class UserServiceImpl implements UserServiceDetails {
private UserRepo userRepo;
@Autowired
public void setUserRepo(UserRepo userRepo) {
this.userRepo = userRepo;
}
@Override
public UserDetails loadUserByUsername(String username)
throws UsernameNotFoundException {
User user=userRepo.findUserByUsername(username);
if(user == null) {
throw …user: {firstName: "loki", lastName: "ch"}
我将此用户存储在会话存储中.
$window.sessionStorage.user = user;
当我用它取回它时
$window.sessionStorage.user,我得到了:
[object Object]
我想要JSON.有什么建议？
@RestController
@RequestMapping(value = "/players")
public class REST {
@RequestMapping(method = RequestMethod.GET)
public List<Player> getAll() {
return service.getAll();
}
@RequestMapping(method = RequestMethod.GET, params = {"team", "score"})
public List<Player> getByPlayerAndScore(@RequestParam(value = "team") String team,
@RequestParam(value = "score", required = false) int score) {
return service.getByPlayerAndScore(team, score);
}
}
Q1:我期待第一种方法为url"/ players"工作(按预期工作)和第二种方法为url工作("/ players？team = xyz","/ players？team = xyz&score = 1000").spring使用method1 for"/ players？team = xyz".即使我指定得分为可选,除非我指定2个参数,弹簧是不使用第二种方法.如何解决这个问题以及编写控制器方法来处理这些类型请求的最佳方法是什么,用户可以发送不同的可用参数集(例如param1和param2,只有param1,只有param2等).
Q2:对于具有不同参数集的第二类查询,如何在DAO层中编写数据库查询.我应该编写单独的方法,每个方法使用不同的查询或一个方法使用多个if语句(如果用户发送'团队'将团队添加到数据库查询,如果用户发送'分数'将其添加到数据库查询......)
class Singleton:
instance = None
def __new__(cls):
if cls.instance is None:
cls.instance = super().__new__(cls)
return cls.instance
singleton_obj1 = Singleton()
singleton_obj2 = Singleton()
print(singleton_obj1)
print(singleton_obj2)
产量
<__main__.Singleton object at 0x10dbc0f60>
<__main__.Singleton object at 0x10dbc0f60>
有人可以解释这一行究竟发生了什么cls.instance = super().__new__(cls).哪一行代码有助于创建这个类Singleton？
$events=Event::all();
if (isset($scheduling) && $scheduling!=="All")
{
$events = $events->filter(function($event) use ($scheduling)
{
return $event->where('scheduling',$scheduling);
});
}
$events=$events->get();
可以有人纠正这个代码.内部过滤器不起作用.无论是否应用过滤器,结果都是相同的.我需要根据条件应用这样的批量过滤器
我正在使用postman客户端对JIRA API进行REST调用.它说"将您的凭据发布到http://jira.example.com:8090/jira/rest/auth/1/session "以获得SESSION.我尝试使用Form-data,application/x-www-form-urlencoded,raw等进行发布.没有任何效果.这是正确的方法.
以下是我正在遵循的教程:https://developer.atlassian.com/jiradev/jira-apis/jira-rest-apis/jira-rest-api-tutorials/jira-rest-api-example-cookie-based-认证
index.js
import { Human } from 'test';
export default Human;
我正在Human从中导入一个命名的出口test。我正在default从导出人，index.js以便允许其他人从而index.js不是导入人test。
例如：
import Human from 'index';
如何将以上2条语句组合index.js成一行？