装配Bean（一）

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装配Bean：

在spring容器内拼凑bean叫做装配。装配bean的时候，需要告诉容器哪些bean以及容器如何使用依赖注入将它们配合在一起。

配置bean的细节：

① scope 的说明：

尽量使用 scope=”singleton”,不要使用prototype,因为这样对我们的性能影响较大.

例子：


package com.hsp.collection;

import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;

public class Department {

    private String name;
    private String[] empName;// 数组
    private List<Employee> empList;// list集合
    private Set<Employee> empsets;// set集合
    private Map<String, Employee> empMaps;// map集合
    private Properties pp;// Properties的使用

    
    //************************************************
    public Set<Employee> getEmpsets() {
        return empsets;
    }

    public void setEmpsets(Set<Employee> empsets) {
        this.empsets = empsets;
    }

    public String[] getEmpName() {
        return empName;
    }

    public void setEmpName(String[] empName) {
        this.empName = empName;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public List<Employee> getEmpList() {
        return empList;
    }

    public void setEmpList(List<Employee> empList) {
        this.empList = empList;
    }

    public Map<String, Employee> getEmpMaps() {
        return empMaps;
    }

    public void setEmpMaps(Map<String, Employee> empMaps) {
        this.empMaps = empMaps;
    }

    public Properties getPp() {
        return pp;
    }

    public void setPp(Properties pp) {
        this.pp = pp;
    }

}


package com.hsp.collection;

public class Employee {
	
	private String name;
	private int id;

	public int getId() {
		return id;
	}

	public void setId(int id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}
}


<?xml version="1.0" encoding="utf-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
	xmlns:tx="http://www.springframework.org/schema/tx"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
				http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-2.5.xsd
				http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">

	<bean id="department" class="com.hsp.collection.Department">
		<property name="name" value="财务部" />

		<!-- 给数组注入值 -->
		<property name="empName">
			<list>
				<value>小明</value>
				<value>小明小明</value>
				<value>小明小明小明小明</value>
			</list>
		</property>

		<!-- 给list注入值 list 中可以有相当的对象 -->
		<property name="empList">
			<list>
				<ref bean="emp2" />
				<ref bean="emp1" />
				<ref bean="emp1" />
				<ref bean="emp1" />
				<ref bean="emp1" />
				<ref bean="emp1" />
				<ref bean="emp1" />
			</list>
		</property>
		
		<!-- 给set注入值  set不能有相同的对象,覆盖了 -->
		<property name="empsets">
			<set>
				<ref bean="emp1" />
				<ref bean="emp2" />
				<ref bean="emp2" />
				<ref bean="emp2" />
				<ref bean="emp2" />
			</set>
		</property>
		
		<!-- 给map注入值 map只要key不一样，就可以装配value -->
		<property name="empMaps">
			<map>
				<entry key="11" value-ref="emp1" />
				<entry key="22" value-ref="emp2" />
				<entry key="22" value-ref="emp1" />
			</map>
		</property>
		
		<!-- 给属性集合配置 -->
		<property name="pp">
			<props>
				<prop key="pp1">abcd</prop>
				<prop key="pp2">hello</prop>
			</props>
		</property>
	</bean>


	<bean id="emp1" class="com.hsp.collection.Employee">
		<property name="name" value="北京" />
		<property name="id" value="1" />
	</bean>
	<bean id="emp2" class="com.hsp.collection.Employee">
		<property name="name" value="天津" />
		<property name="id" value="2" />
	</bean>
</beans>


package com.hsp.collection;

import java.util.Enumeration;
import java.util.Iterator;
import java.util.Map;
import java.util.Properties;
import java.util.Map.Entry;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class App1 {

	/**
	 * @param args
	 */
	public static void main(String[] args) {

		ApplicationContext ac = new ClassPathXmlApplicationContext("com/hsp/collection/beans.xml");
		Department department = (Department) ac.getBean("department");
		System.out.println(department.getName());

		System.out.println("**********通过数组取出数据*****");
		for (String emName : department.getEmpName()) {
			System.out.println(emName);
		}

		System.out.println("**********通过list集合取出数据*****");
		for (Employee e : department.getEmpList()) {
			System.out.println("name=" + e.getName() + " " + e.getId());
		}

		System.out.println("**********通过set集合取出数据*****");
		for (Employee e : department.getEmpsets()) {
			System.out.println("name=" + e.getName() + " " + e.getId());
		}

		System.out.println("*******通过map集合取出数据 迭代器****");
		// 1.迭代器
		Map<String, Employee> empmaps = department.getEmpMaps();
		Iterator it = empmaps.keySet().iterator();
		while (it.hasNext()) {
			String key = (String) it.next();
			Employee emp = empmaps.get(key);
			System.out.println("key=" + key + " " + emp.getName()+ " " + emp.getId());
		}

		System.out.println("*******通过map集合取出数据 简洁方法****");
		// 2.简洁方法
		for (Entry<String, Employee> entry1 : department.getEmpMaps().entrySet()) {
			System.out.println(entry1.getKey() + " " + entry1.getValue().getName()+ " " + entry1.getValue().getId());
		}

		System.out.println("*****通过Propertis取出数据*****");
		Properties pp = department.getPp();
		// System.out.println(pp.get("pp1").toString());
		for (Entry<Object, Object> entry : pp.entrySet()) {
			System.out.println(entry.getKey().toString() + " " + entry.getValue().toString());
		}
		
		System.out.println("*****通过Enumeration取出*****");
		Enumeration en = pp.keys();
		while (en.hasMoreElements()) {
			String key = (String) en.nextElement();
			System.out.println(key + " " + pp.getProperty(key));
		}
	}

}


财务部
**********通过数组取出数据*****
小明
小明小明
小明小明小明小明
**********通过list集合取出数据*****
name=天津 2
name=北京 1
name=北京 1
name=北京 1
name=北京 1
name=北京 1
name=北京 1
**********通过set集合取出数据*****
name=北京 1
name=天津 2
*******通过map集合取出数据 迭代器****
key=11 北京 1
key=22 北京 1
*******通过map集合取出数据 简洁方法****
11 北京 1
22 北京 1
*****通过Propertis取出数据*****
pp2 hello
pp1 abcd
*****通过Enumeration取出*****
pp2 hello
pp1 abcd