"Spring Combat"--7 injection of complex collection types

Before explaining the basic types of spring and the injection of bean references, let's take a look at the injection of complex collection types, such as List, Set, map, and so on.

Mastering multiple languages is a basic skill for programmers.

Here we do a small example, the programmer is a bean instance, and the Master programming language is put into a collection type to inject.

In simple terms:

A list is a collection that is identified by an ordinal number.

Set is similar to list but the element does not allow repetition.

Map is a self-defined key-value pair, and the key value can be any type.

The Bean implementation class

 Public classProgrammer { PublicProgrammer () {}//injection of List and set    PrivateCollection<language>language;  Public voidSetLanguage (collection<language>language) {         This. Language =language; }     Public voidworking () { for(Language lang:language) {System. out. println ("working on"+lang.using()); }    }    //the injection of map    PrivateMap<string,language>Lang;  Public voidSetlang (map<string,language>Lang) {         This. lang =Lang; }     Public voidstudying () { for(String key:lang.keySet ()) {System. out. Print (key+" : "); Language Language= lang.Get(key); System. out. println ("studying on"+language.using()); }    }}

Some of the other required interfaces and implementation classes

 Public Interface Language {    publicusing();}

View Code

 Public class Java implements language{    publicusing() {        return' Java " ;    }    }

View Code

 Public class CPP implements language{    publicusing() {        return' C + + " ;    }}

View CodeThe spring configuration file is as follows

<?xml version="1.0"encoding="UTF-8"? ><beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"xmlns="Http://www.springframework.org/schema/beans"xsi:schemalocation="Http://www.springframework.org/schema/beanshttp//www.springframework.org/schema/beans/spring-beans-3.0.xsd "><bean id="Java" class="Com.spring.test.collector.Java"/> <bean id="CPP" class="com.spring.test.collector.Cpp"/> <bean id="Xingoo" class="Com.spring.test.collector.Programmer"> <property name="language"> <list> <refbean="Java"/> <refbean="CPP"/> </list> </property> </bean> <bean id="Halo" class="Com.spring.test.collector.Programmer"> <property name="language"> <Set> <refbean="Java"/> </Set> </property> </bean> <bean id="Zhang3" class="Com.spring.test.collector.Programmer"> <property name="Lang"> <map> <!--key is a string key-ref key for other beans--<!--value value is str ing value-ref value for other bean references--<entry key="Java"value-ref="Java"/> <entry key="CPP"value-ref="CPP"/> </map> </property> </bean></beans>

Gets the bean instance and uses the

 Public classTest { Public Static voidMain (string[] args) {ApplicationContext ctx=NewClasspathxmlapplicationcontext ("Bean.xml"); System. out. println ("[Xingoo]"); Programmer Programmer= (Programmer) Ctx.getbean ("Xingoo");        Programmer.working (); System. out. println ("[Halo]"); Programmer Programmer1= (Programmer) Ctx.getbean ("Halo");        Programmer1.working (); System. out. println ("[Zhang3]"); Programmer Programmer2= (Programmer) Ctx.getbean ("Zhang3");    Programmer2.studying (); }}

Execution Result:

[xingoo]working on javaworking on C+ +[halo]working on Java[zhang3]java:studying on javacpp:studying on C< /c1>++

"Spring Combat"--7 injection of complex collection types