I am new to spring mvc and DI. I have came to know about the flow of the spring project and i know how the web projects in spring mvc is developed and worked on few projects too. All the annotation uses and xml configuration files in the spring mvc. But i am confused where the DI is used? and how the DI is implemented in spring with the help of IOC?? Can anyone please explain me the concept
我是春季mvc和DI的新手。 我已经开始了解春季项目的流程，并且我知道春季mvc中的web项目是如何开发的，并且也在少数项目上工作。 Spring MVC中的所有注释都使用xml配置文件。 但我很困惑在哪里使用DI？ 以及DI在IOC的帮助下如何在春季实施？ 任何人都可以向我解释DI和IOC的概念以及它们在spring mvc中的实现。 提前致谢！！！ DI和IOC通过web.xml创建dispatcherservlet。 从Spring MVC文档：DispatcherServlet为请求
This question already has an answer here: What is so bad about singletons? [closed] 36 answers If it was public, everybody could use Singleton.instance and would complain because it's null. Making it private forces them to use getInstance() , which guarantees to return a non-null instance. If it wasn't static, it would be an instance variable of Singleton, and you would thus need
这个问题在这里已经有了答案： 单身人士有什么不好？ [已关闭] 36个回答 如果它是公开的，每个人都可以使用Singleton.instance并会因为它为空而抱怨。 使它成为私人的强制他们使用getInstance() ，它保证返回一个非空的实例。 如果它不是静态的，它将是一个Singleton的实例变量，因此你需要一个Singleton实例来访问唯一的Singleton实例，这没有多大意义。
Possible Duplicate: What is so bad about Singletons? One of the drawbacks of using Singleton, as widely discussed in this stackoverflow question is that they hide the class dependencies in the code. However, we can make a singleton implement an interface while still obeying the two rules of singleton: single instance and global scope. Why is Singleton still said to hide dependencies? Hid
可能重复： 单身人士有什么不好？ 使用Singleton的一个缺点是，他们在代码中隐藏了类依赖。 但是，我们可以让单例实现一个接口，同时仍然遵守单例的两个规则：单实例和全局作用域。 为什么辛格尔顿仍然说隐藏依赖关系？ 隐藏依赖意味着从代码到单例没有可见的链接，因为单例可以从任何地方调用。 让单例实现接口不会改变问题。
There has been a lot written about this topic: Restarting transaction in MySQL after deadlock Deadlock found when trying to get lock; try restarting transaction : @RetryTransaction MySQL JDBC: Is there an option for automatic retry after InnoDB deadlock? Working around MySQL error "Deadlock found when trying to get lock; try restarting transaction" ... many more I find part
关于这个话题已经有很多文章了： 死锁后重新启动MySQL中的事务 尝试锁定时发现死锁; 尝试重新启动事务：@RetryTransaction MySQL JDBC：在InnoDB死锁之后是否有自动重试的选项？ 解决MySQL错误“试图锁定时发现死锁;尝试重新启动事务” ... 还有很多 我发现最后接受的答案特别有趣： 如果您正在使用InnoDB或任何行级事务性RDBMS，则任何写入事务都可能导致死锁，即使在完全正常的情况下也是如此。 较大的表，较大
I am yet to find a high-level definition of Spring beans that I can understand. I see them referenced often in Grails documentation and books, but I think that understanding what they are would be beneficial. So what are Spring beans? How can they be used? Do they have something to do with Dependency Injection? The objects that form the backbone of your application and that are managed by t
我还没有找到我能理解的Spring bean的高级定义。 我经常在Grails文档和书中看到它们，但我认为理解它们是有益的。 那么Spring bean是什么？ 他们如何使用？ 他们与依赖注入有关吗？ 构成应用程序主干和由Spring IoC *容器管理的对象称为bean。 bean是一个实例化，组装并由Spring IoC容器管理的对象。 这些bean是使用您提供给容器的配置元数据创建的，例如，以XML定义的形式。 更多来从SpringSource学习bean和范围：
I would like to arrange for a Spring instance object to be a Mock instead of the normally constructed instance in order to complete an integration test. The object being mocked is not injected by Spring into a member variable but rather is accessed by querying the Spring context. An example (for reference): class Service { public void doIt() { Helper helper = new Helper();
我想安排一个Spring实例对象作为Mock而不是通常构造的实例来完成集成测试。 被模拟的对象不是被Spring注入成员变量，而是通过查询Spring上下文来访问。 一个例子（供参考）： class Service { public void doIt() { Helper helper = new Helper(); helper.doIt(); } } class Helper { public void doIt() { BeanFactory factory = getBeanFactory(); // A function to get the bean fac
We have a project that uses Spring annotations to configure its context. To test this project we are using Mockito and it's Spring extension. In tests I need to override some beans with mock/spy version. With the @Mock / @Spy and @InjectMock annotations I have been able to use spy for beans using autowiring mechanism. Now I have a third party component which create another Spring conte
我们有一个使用Spring注释来配置其上下文的项目。 为了测试这个项目，我们使用Mockito ，它是Spring扩展。 在测试中，我需要用模拟/间谍版本来重写一些bean。 使用@Mock / @Spy和@InjectMock注释，我可以使用自动装配机制使用spy进行bean。 现在我有一个第三方组件创建另一个Spring上下文，然后将这两个上下文合并在一起。 该第三方组件使用对上下文的调用来检索bean： applicationContext.getBean(key); 在这种情况下
When testing with spring and @ContextConfiguration Is there an option to exclude some of the base class contexts? for example @ContextConfiguration(locations = {"context1.xml", "context2.xml"}) public class Base{ and extending class public class someClass extends Base{ now I want someClass to use context1.xml but NOT context2.xml. is there a way to exclude it? the issue is: I have a base c
当使用spring和@ContextConfiguration进行测试时是否有一个选项可以排除某些基类上下文？ 例如 @ContextConfiguration(locations = {"context1.xml", "context2.xml"}) public class Base{ 并扩大课程 public class someClass extends Base{ 现在我想让someClass使用context1.xml而不使用context2.xml。 有没有办法排除它？ 问题是：我的所有测试（300个测试）都有一个基类。 我希望所有的人都使用CONTEXT1这是一个模拟
I'd like to write some tests that check the XML Spring configuration of a deployed WAR. Unfortunately some beans require that some environment variables or system properties are set. How can I set an environment variable before the spring beans are initialized when using the convenient test style with @ContextConfiguration? @RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration(loca
我想编写一些测试来检查部署的WAR的XML Spring配置。 不幸的是一些bean需要设置一些环境变量或系统属性。 在使用方便的测试样式和@ContextConfiguration时，如何在spring bean初始化之前设置一个环境变量？ @RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration(locations = "classpath:whereever/context.xml") public class TestWarSpringContext { ... } 如果我使用注释来配置应用程序上下文，那么在Spring上
In spring scopes, if I use singleton ,it initialize all beans when it loads the configuration files before executing the logic. But if I use prototype as scope,the bean will be initialized as per the call.Am I right? Does singleton work as static and prototype as instance variable? MainJava.java: import org.springframework.context.support.AbstractApplicationContext; import org.springframewor
在Spring范围中，如果我使用singleton，它在执行逻辑之前加载配置文件时初始化所有的bean。 但是如果我使用原型作为范围，那么这个bean会根据这个调用进行初始化。我对吗？ 单身人士是否像实例变量一样工作为静态和原型？ MainJava.java： import org.springframework.context.support.AbstractApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; public class MainJava { p