Spring some summary

Three ways to instantiate beans in Spring: 1) using class constructors   <bean id= "OrderService" class= "Cn.itcast.OrderService"/> 2) Using static factory methods for instantiation   <bean id= "Personservice" class= "Cn.itacast.OrderFactory" factory-method= "Createorder"/>   public class orderfactory{       public static Orderservicebean Createorder () {    &N Bsp        return new Orderservicebean ();       } } 3) Using instance factory method instantiation   & Nbsp;<bean id= "Personservicefactory" class= "cn.itcast.service.OrderFactory"/>   <bean id= " Personservice "factory-bean=" Personservicefactory "factory-method=" Createorder "/>   public class orderfactory{       public static Orderservicebean Createorder () {          & nbsp  return new Orderservicebean ();       } }  beans scope:  .singleton    In each spring IOC container, a bean defines only one instance of an object. By default, the     Bean is initialized when the container is started. ButIs that we can specify the bean node's lazy-init= "true" to defer initialization of the bean, which is only initialized when the     bean is used for the first time. such as:    <bean id= "xxx" class= "Class full class name" lazy-init= "true"/>    if you want to apply lazy initialization to all beans, You can set defult-lazy-init= "true" at the root node beans, as follows:    <beans default-lazy-init= "true" ...> . prototype       Every bean that gets from the container is a new object.   .request  .session  Global session  Injection dependent objects   &NBSP;1) Basic type Object injection    <bean id= " OrderService "class=" Orderservicebean ">        <constructor-arg index=" 0 "type=" Java.lang.String "value=" xxx "/>  //constructor injection         <property name=" name "value=" Zhao "/>  //Zodiac Setter Method injection    </bean>   2) Inject other bean    methods 1:        <bean id= "Orderdao" class= "service. Orderdaobean "/><bean id=" OrderService "class=" service. Orderservicebean ">   <property name=" Orderdao "ref=" Orderdao "/></bean>    Method 2: Use the innerDepartment Bean (internal Bean cannot be used by other beans)          <bean id= "OrderService" class= "service. Orderservicebean ">   <property name=" Orderdao ">        <bean class=" Service. Orderdaobean "/>   </property></bean> assemble assembly type:   public class Orderservicebean { Private set<string> sets=new hashset<string> ();p rivate list<string> lists=new ArrayList<String > ();p rivate Properties Properties=new properties ();p rivate map<string,string> maps=new hashmap<string, String> ();  //setter and Getter methods omitted ...} The configuration file for the collection is as follows: <?xml version= "1.0" encoding= "UTF-8"? ><beans xmlns= "http://www.springframework.org/schema/ Beans "xmlns:xsi=" http://www.w3.org/2001/XMLSchema-instance "xsi:schemalocation=" http://www.springframework.org/ Schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd ">  <bean id=" order " class= "Cn.itcast.service.OrderServiceBean" > <property Name= "Lists" ><list><value>hujingwei</value><value>wanglei</value></list ></property> <property name= "Sets" ><set><value>set</value></set> </property> <property name= "Maps" ><map><entry key= Hujingwei "value="/><entry key= "Wanglei" value= "/></map></property> <property name=" Properties "><props> <prop key= ">sss</prop></props></property> </bean></beans> " Automatic assembly   in Java code, the @autowired or @resource annotation is used to assemble, the difference between the two annotations is:  @Autowired by default is assembled by type, @Resource by default is assembled by name, when the name match is not found   is only assembled by type.   @Autowired annotations are assembled by assembly type, by default the dependent object must exist, and if   is allowed to be a null value, you can set its Required property to false. If we want to assemble by name, we can use it together with @qualifier annotations  . The following:  @Autowired   @Qualifier ("Personorderbean")   private Persondao Persondao;

Spring Some summary