blocks|key|1354248|text|它指示在请求尝试访问servlet之前不会启动它。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1354249|如果load-+on+-startup大于或等于0，那么当容器启动时，它将按照您设置的load+on+startup值的升序启动servlet+(例如，0、1、2、5、10，依此类推)。|1354250|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

It indicates that the servlet won't be started until a request tries to access it.

If load-on-startup is greater than or equal to zero then when the container starts it will start that servlet in ascending order of the load on startup value you put there (ie 0, 1 then 2 then 5 then 10 and so on).

blocks|key|1354280|text|是的，它可以有相同的value....the，给启动时加载编号的原因是定义服务器加载所有servlet的顺序。值为0的servlet将首先加载，值为1的servlet将在此之后加载。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1354281|如果两个servlet在启动时加载的值与相同，那么将按照从上到下在web.xml中声明它们的方式进行加载。首先加载web.xml中最先出现的servlet，然后再加载另一个servlet。|1354282|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

yes it can have same value....the reason for giving numbers to load-on-startup is to define a sequence for server to load all the servlet. servlet with 0 load-on-startup value will load first and servlet with value 1 will load after that. 

if two servlets will have the same value for load-on-startup than it will be loaded how they are declared in the web.xml from top to bottom. the servlet which comes first in the web.xml will be loaded first and the other will be loaded after that.

blocks|key|1569506|text|servlet容器在启动期间或发出第一个请求时加载servlet。servlet的加载取决于"web.xml“文件中的”启动时加载“属性。如果属性有一个正整数(0到128)，那么servlet将随容器的加载一起加载，否则它将在第一个服务请求到来时加载。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1569507|当servlet被加载时，一旦它被请求，那么它就被称为“延迟加载”。|1569508|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

The servlet container loads the servlet during startup or when the first request is made. The loading of the servlet depends on the attribute "load-on-startup" in "web.xml" file. If the attribute has a positive integer(0 to 128) then the servlet is load with the loading of the container otherwise it loads when the first request comes for service.

When the servlet is loaded once it gets request then it is called "Lazy loading".

blocks|key|1354377|text|如果值<0，则在请求到来时实例化serlet，否则>=0容器将按值的递增顺序加载。如果2个或更多的servlet具有相同的值，则web.xml中声明的servlet的顺序。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1354378|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

If the value is &lt;0, the serlet is instantiated when the request comes, else >=0 the container will load in the increasing order of the values. if 2 or more servlets have the same value, then the order of the servlets declared in the web.xml.

blocks|key|1569631|text|正如在其他答案中所述，这个servlet+0是可以接受的，如果没有任何其他load-on-startup+article，这将在加载和部署期间优先加载。load-on+statup的最佳用途是在第一个请求到来之前加载需要更长时间初始化的servlet，比如创建连接池或进行网络调用或占用大量资源的servlet，这将显著减少最初几个请求的响应时间。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1569632|entityMap|0|LINK|mutability|MUTABLE|url|http://javarevisited.blogspot.com/2011/12/load-on-startup-servlet-webxml-example.html^0|11|N|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

As stated on other answer and this <a href="http://javarevisited.blogspot.com/2011/12/load-on-startup-servlet-webxml-example.html" rel="nofollow">load-on-startup article</a> zero is acceptable and in the absent of any other servlet this will take priority on loading and loaded during deployment. Best use of load-on statup is to load servlets which takes longer time to initialize well before first request come like servlets which creates connection pool or make network call or hold bulky resource, this will significantly reduce response time for first few request.

blocks|key|1354549|text|-->+(缺少启动时加载)标签首先当servlet部署到服务器中时，服务器负责创建servlet对象。例如:假设Servlet部署在服务器上，(Servlet对象在服务器上不可用)客户端第一次向servlet发送请求，然后服务器在默认构造函数的帮助下创建servlet对象，并立即调用init()。从那时起，当客户端发送请求时，只有服务方法将执行，因为对象已经可用|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1354550|如果在部署描述符中使用了load-+on+-start标记:在部署本身时，服务器根据标记之间提供的正值为servlet创建servlet对象。servlet类的对象创建顺序为0-128，首先创建编号为0的servlet，然后再创建其他编号。|1354551|如果我们为web.xml中的两个servlet提供相同的值，那么对象的创建将基于类在web.xml中的位置进行，并且在不同的服务器上也会有所不同。|1354552|如果我们在load+on+start标签之间提供了负值，那么服务器将不会创建servlet对象。|1354553|服务器为servlet创建对象的其他场景。|1354554|如果我们在web.xml中不使用load+on+start+up+tag，那么当每个客户端第一次发送请求时，项目就会被部署，服务器创建对象，服务器负责调用它的生命周期方法。然后，如果在服务器中修改了.class+(Tomcat)。同样，客户端发送修改servlet的请求，但是在tomcat的情况下，不会创建新的对象，并且服务器将使用现有的对象，除非服务器重新启动。但是在web逻辑类中，当任何.class文件在服务器中被修改时，没有重启服务器，如果它收到请求，服务器就会调用现有servlet上的destroy方法，并创建一个新的servlet对象，并调用init()进行初始化。|1354555|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|N|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|O|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|P|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|Q|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|R|8|@]|9|@]|A|$]]|$1|J|3|K|5|6|7|S|8|@]|9|@]|A|$]]|$1|L|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|M|$]]

--> 
(Absence of load-on-start-up) tag
First of all when ever servlet is deployed in the server, It is the responsibility of the server to creates the servlet object.
 Eg: Suppose Servlet is deployed in the server ,(Servlet Object is not available in server) client sends the request to the servlet for the first time then server creates the servlet object with help of default constructor 
and immediately calls init() . From that when ever client sends the request only service method will get executed as object is already available

If load-on-start-up tag is used in deployment descriptor:
 At the time of deployment itself the server creates the servlet object for the servlets based on the positive value provided in between the tags. The Creation of objects for the servlet classes will follow from 0-128
 0 number servlet will be created first and followed by other numbers.

If we provide same value for two servlets in web.xml then creation of objects will be done based on the position of classes in web.xml also varies from server to server.

If we provide negative value in between the load on start up tag then server wont create the servlet object. 

<h2>Other Scenarios where server creates the object for servlet.</h2>

If we dont use load on start up tag in web.xml, then project is deployed when ever client sends the request for the first time server creates the object and server is responsible for calling its life cycle methods. Then if a .class is been modified in the server(tomcat).
again client sends the request for modified servlet but in case of tomcat new object will not created and server make use of existing object unless restart of server takes place.
But in class of web-logic when ever .class file is modified in the server with out restarting the server if it receives a request then server calls the destroy method on existing servlet and creates a new servlet object and calls init() for its initilization.

blocks|key|1354599|text|它很简单，你甚至都没有料到。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1354600|如果该值为正，则在容器启动时加载|1354601|如果该值不是正数，则在发出请求时加载servelet。|1354602|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

It is simple as you don't even expect.

If the value is positive it loaded when the container starts

If the value is not positive than the servelet is loaded when the request is made.

I am getting a bit confused here. In our application we are having a few servlets defined. Here is the excerpt from the <code>web.xml</code> for one of the servlets:

<pre class="lang-xml prettyprint-override"><code>&lt;servlet&gt;
 &lt;servlet-name&gt;AxisServlet&lt;/servlet-name&gt;
 &lt;display-name&gt;Apache-Axis Servlet&lt;/display-name&gt;
 &lt;servlet-class&gt;com.foo.framework.axis2.http.FrameworkServlet&lt;/servlet-class&gt;
 &lt;load-on-startup&gt;0&lt;/load-on-startup&gt;
&lt;/servlet&gt; 
</code></pre>

As per my understanding the value for the <code>&lt;load-on-startup&gt;</code> has to be a positive integer in order for it to get loaded automatically. I looked up on google but the responses I came across only added to my confusion.

What does the servlet <load-on-startup> value signify

服务器

容器

我在这里有点困惑。在我们的应用程序中，我们定义了一些servlet。下面是其中一个servlet的web.xml摘录：<servlet> <servlet-name>AxisServlet</servlet-name> <display-name>Apache-Axis Servlet</display-n...

问servlet <load-on-startup>值意味着什么
EN

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问servlet <load-on-startup>值意味着什么EN

社区

活动

资源

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问servlet <load-on-startup>值意味着什么
EN