Spring学习笔记-配置文件

Spring入门

1.导入坐标（pom.xml）

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context</artifactId>
      <version>5.3.15</version>
    </dependency>

2.创建接口类

package org.example.dao;

public interface UserDao {
    void save();
}

3.接口实现

package org.example.Impl;

import org.example.dao.UserDao;

public class UserDaoImpl implements UserDao {
    @Override
    public void save() {
        System.out.println("savr runing...");
    }
}

4.创建applicationContext.xml(resouces文件下)配置Bean

<bean id="userDao" class="org.example.Impl.UserDaoImpl"></bean>

5.创建applicationContext对象getBean

public class SpringTest {
    @Test
    public void test1(){
        ApplicationContext app = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserDao userDao = (UserDao) app.getBean("userDao");
        userDao.save();
    }
        
}

Spring配置文件

Bean标签基本配置

基本属性

  1. id:Bean实例在Spring容器中的唯一标识
  2. class：Bean的全限定名称
  3. scope:对象作用范围，取值如下：

  • single：默认值，单例的，当Spring核心被加载时，实例化配置的Bean实例

  • prototype:多例的,当调用getBean()方法时实例化Bean

  • request:WEB项目中,Spring创建一个Bean对象，将对象存到request域中

  • session：WEB项目中,Spring创建一个Bean对象，将对象存到session域中

  • global session：WEB项目中,应用在portlet中，如果没有portlet环境，那么global Session相当于session

Bean生命周期配置

  1. init-method：指定类中的初始化方法名称

  2. destroy-method：指定类中销毁方法名称

<bean id="userDao" class="org.example.Impl.UserDaoImpl" scope="singleton" init-method="init" destroy-method="destory"></bean>

public class UserDaoImpl implements UserDao {

    public UserDaoImpl() {
        System.out.println("对象创建...");
    }

    @Override
    public void save() {
        System.out.println("savr runing...");
        }

    public void init(){
        System.out.println("初始化方法....");
        }

    public void destory(){
        System.out.println("销毁方法....");
    }
}

Bean实例化的三种方式

无参构造方法实例化
<bean id="userDao" class="org.example.Impl.UserDaoImpl"></bean>

public class UserDaoImpl implements UserDao {

    public UserDaoImpl() {}
}
工厂静态方法实例化
<bean id="userDao" class="org.example.factory.StaticFactory" factory-method="getUserDao"></bean>

public class StaticFactory {
    public static UserDao getUserDao(){
        return new UserDaoImpl();
    }
}
工厂实例方法实例化
<bean id="factory" class="org.example.factory.DynameicFactory" ></bean>
<bean id="userDao" factory-bean="factory" factory-method="getUserDao"></bean>

public class DynameicFactory {
    public UserDao getUserDao(){
        return new UserDaoImpl();
    }
}

对象引用依赖注入方式

构造方法
<bean id="userDao" class="org.example.Impl.UserDaoImpl"></bean>
    <bean id="UserService" class="org.example.Impl.UserServiceImpl">
        <constructor-arg name="userDao" ref="userDao"></constructor-arg>
    </bean>

public class UserServiceImpl implements UserService {

    private UserDao userDao;
    //构造方法注入
    public UserServiceImpl(UserDao userDao){
        this.userDao = userDao;
    }
}
set()方法
<bean id="userDao" class="org.example.Impl.UserDaoImpl"></bean>
    <bean id="UserService" class="org.example.Impl.UserServiceImpl">
        <property name="userDao" ref="userDao"></property> 
<!--name:注入Bean的id，ref:调用方法（setUserDao），去set首字母小写-->
    </bean>

public class UserServiceImpl implements UserService {

    private UserDao userDao;
    public void setUserDao(UserDao userDao){
        this.userDao = userDao;
    }

    @Override
    public void save() {
        userDao.save();
    }
}
p命名空间注入(本质set()方法注入，更方便)
<beans xmlns:p="http://www.springframework.org/schema/p">
<!--引入p命名空间-->

<bean id="userDao" class="org.example.Impl.UserDaoImpl"></bean>
<bean id="UserService" class="org.example.Impl.UserServiceImpl" p:userDao-ref="userDao"></bean>

依赖注入数据类型

普通数据类型
<bean id="userDao" class="org.example.Impl.UserDaoImpl">
        <property name="username" value="zhangsan"></property>
        <property name="age" value="18"></property>
    </bean>

public class UserDaoImpl implements UserDao {

    private String username;
    private Integer age;

    public void setUsername(String username) {
        this.username = username;
    }

    public void setAge(Integer age) {
        this.age = age;
    }
}
集合数据类型
    <bean name="user1" class="org.example.domain.User">
        <property name="name" value="Tom"></property>
        <property name="addr" value="sh"></property>
    </bean>
    <bean name="user2" class="org.example.domain.User">
        <property name="name" value="Sum"></property>
        <property name="addr" value="bj"></property>
    </bean>
    
    <bean id="userDao" class="org.example.Impl.UserDaoImpl">
        <property name="strList">
            <list>
                <value>aaa</value>
                <value>abb</value>
                <value>abc</value>
            </list>
        </property>
    
        <property name="userMap">
            <map>
                <entry key="u1" value-ref="user1"></entry>
                <entry key="u2" value-ref="user2"></entry>
            </map>
        </property>
    
        <property name="properties">
            <props>
                <prop key="p1">111</prop>
                <prop key="p2">122</prop>
                <prop key="p3">123</prop>
            </props>
        </property>
        <property name="age" value="18"></property>
    </bean>

public class UserDaoImpl implements UserDao {

    private List<String> strList;
    private Map<String, User> userMap;
    private Properties properties;

    public void setStrList(List<String> strList) {
        this.strList = strList;
    }

    public void setUserMap(Map<String, User> userMap) {
        this.userMap = userMap;
    }

    public void setProperties(Properties properties) {
        this.properties = properties;
    }
}

Spring配置文件

<import resource="applicationContext-***.xml"/>
posted @ 2022-04-04 18:41  YL_Hello  阅读(24)  评论(0)  编辑  收藏  举报