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疾速配置
创立我的项目
下载并引入依赖包
下载地址:Spring-5.3.9
官网下载方式参考:官网下载 Spring 的 jar 包教程
编写代码
写一个一般类用作注入的 bean:
package com.hqz;
public class Student {public void study() {System.out.println("I am learning");
}
}
编写配置文件(配置文件的头部信息是固定的):
<?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/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="student" class="com.hqz.Student"/>
</beans>
测试类:
package com.hqz;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class Test {public static void main(String[] args) {ApplicationContext applicationContext = new ClassPathXmlApplicationContext("bean.xml");
Student student = applicationContext.getBean("student", Student.class);
student.study();}
}
最终的我的项目构造如下图所示:
Bean 治理
XML 形式
创建对象
<bean id="dao" class="com.hqz.UserDao"></bean>
三种属性注入形式
set 办法注入
public Class Book {
private String name;
public void SetName(String name) {this.name = name;}
}
<bean id="book" class="com.hqz.Book">
<property name="name" value="金瓶梅"></property>
</bean>
有参结构注入
public Class Orders {
private String name;
private String address;
public Orders(String name, String address) {
this.name = name;
this.address = address;
}
}
<bean id="orders" class="com.hqz.Orders">
<!-- 通过属性名称来注入 -->
<constructor-arg name="name" value="西游记"></constructor-arg>
<!-- 通过属性索引值来注入 -->
<constructor-arg index="0" value="中国"></constructor-arg>
</bean>
p 名称空间注入
- 第一步:增加 p 名称空间在配置文件中
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
<!-- 增加 p 名称空间在配置文件中 -->
xmlns:p="http://www.springframework.org/schema/p"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<bean id="user" class="com.hqz.User"/>
</beans>
- 第二步:进行属性注入,在 bean 标签外面进行操作
<bean id="book" class="com.hqz.Book" p:name="三国演义"></bean>
各种数据类型注入
注入 null 值
<bean id="book" class="com.hqz.Book">
<property name="name">
<null/>
</property>
</bean>
注入特殊符号
<bean id="book" class="com.hqz.Book">
<!-- 谬误写法 -->
<property name="name" value="<< 南京 >>"></property>
<!-- 正确写法 -->
<property name="name">
<value>
<![CDATA[<< 南京 >>]]>
</value>
</property>
</bean>
注入内部 bean
应用 ref 注入
<bean id="userService" class="com.hqz.service.impl.UserServiceImpl">
<property name="userDao" ref="userDaoImplId" />
</bean>
<bean id="userDaoImplId" class="com.hqz.dao.impl.UserDaoImpl" />
注入外部 bean
<!-- 形式一:外部 bean -->
<bean id="emp" class="com.hqz.bean.Emp">
<property name="name" value="张三"/>
<property name="sex" value="女"/>
<property name="dept">
<bean id="dept" class="com.hqz.bean.Dept">
<property name="name" value="技术部"/>
</bean>
</property>
</bean>
<!-- 形式二:级联赋值 -->
<bean id="emp" class="com.hqz.bean.Emp">
<property name="name" value="张三"/>
<property name="sex" value="女"/>
<property name="dept" ref="dept" />
</bean>
<bean id="dept" class="com.hqz.bean.Dept">
<property name="name" value="财务部"/>
</bean>
<!-- 形式三 -->
<bean id="emp" class="com.hqz.bean.Emp">
<property name="name" value="张三"/>
<property name="sex" value="女"/>
<property name="dept" ref="dept"/>
<property name="dept.name" value="行政部" />
</bean>
<bean id="dept" class="com.hqz.bean.Dept" />
// 部门类
package com.hqz.bean;
public class Dept {
private String name;
public String getName() {return name;}
public void setName(String name) {this.name = name;}
}
// 员工类
package com.hqz.bean;
public class Emp {
private String name;
private String sex;
private Dept dept;
public Dept getDept() {return dept;}
public void setDept(Dept dept) {this.dept = dept;}
public String getName() {return name;}
public void setName(String name) {this.name = name;}
public String getSex() {return sex;}
public void setSex(String sex) {this.sex = sex;}
}
注入汇合属性
数组类型属性注入
public class Student {private String[] names;
public void setNames(String[] names) {this.names = names;}
}
<bean id="student" class="com.hqz.Student">
<property name="names">
<!-- 数组类型属性注入 -->
<array>
<value> 张三 </value>
<value> 李四 </value>
</array>
</property>
</bean>
list 类型属性注入
public class Student {
private List<String> names;
public void setNames(List<String> names) {this.names = names;}
}
<bean id="student" class="com.hqz.Student">
<property name="names">
<!-- list 类型属性注入 -->
<list>
<value> 张三 </value>
<value> 李四 </value>
</list>
</property>
</bean>
map 类型属性注入
public class Student {
private Map<String, String> maps;
public void setMaps(Map<String, String> maps) {this.maps = maps;}
}
<bean id="student" class="com.hqz.Student">
<property name="maps">
<!-- map 类型属性注入 -->
<map>
<entry key="name" value="张三"/>
<entry key="age" value="20"/>
</map>
</property>
</bean>
set 类型属性注入
public class Student {
private Set<String> sets;
public void setSets(Set<String> sets) {this.sets = sets;}
}
<bean id="student" class="com.hqz.Student">
<property name="sets">
<!-- set 类型属性注入 -->
<set>
<value> 李四 </value>
</set>
</property>
</bean>
注入对象到汇合中
public class Book {
private String bookName;
public void setBookName(String bookName) {this.bookName = bookName;}
}
public class Library {
private List<Book> bookList;
public void setBookList(List<Book> bookList) {this.bookList = bookList;}
}
<bean id="book" class="com.hqz.Book">
<property name="bookName" value="语文" />
</bean>
<bean id="library" class="com.hqz.Library">
<property name="bookList">
<list>
<ref bean="book"></ref>
</list>
</property>
</bean>
提取汇合注入
把通用的汇合列表提取进去,不便在多个中央进行援用。
- 引入 util 命名空间
<?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:util="http://www.springframework.org/schema/util"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd">
</beans>
- 创立 bean 类
public class Library {
private List<String> bookList;
public void setBookList(List<String> bookList) {this.bookList = bookList;}
}
- 编写配置类
<util:list id="bookListId">
<value>《三国演义》</value>
<value>《西游记》</value>
<value>《水浒传》</value>
<value>《红楼梦》</value>
</util:list>
<bean id="library" class="com.hqz.Library">
<property name="bookList" ref="bookListId"/>
</bean>
内部属性文件
- 引入命名空间
xmlns:context=”http://www.springframework.org/schema/context”
<?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:util="http://www.springframework.org/schema/util"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
</beans>
-
编写内部文件
jdbc.properties
prop.driverClass=com.mysql.jdbc.Driver
prop.url=jdbc:mysql://localhost:3306/userDb
prop.userName=root
prop.password=root
- 配置
<!-- 引入内部属性文件 -->
<context:property-placeholder location="classpath:jdbc.properties"/>
<!-- 配置连接池 -->
<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
<property name="driverClassName" value="${prop.driverClass}"/>
<property name="url" value="${prop.url}"/>
<property name="userName" value="${prop.userName}"/>
<property name="password" value="${prop.password}"/>
</bean>
注解形式
创建对象
- 配置文件中开启组件扫描
<?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"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 开启组件扫描
1、如果扫描多个名,能够用逗号隔开
2、或者扫描下层目录
-->
<context:component-scan base-package="com.hqz.dao,com.hqz.service"/>
</beans>
- 增加注解
package com.hqz.service;
import org.springframework.stereotype.Component;
// 在注解外面 value 属性值能够不写
// 默认值是类名称,首字母小写
@Component(value = "userService")
public class UserService {public void add() {System.out.println("中华人民共和国");
}
}
- 组件扫描配置
<?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"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<!-- 开启组件扫描
1、如果扫描多个名,能够用逗号隔开
2、或者扫描下层目录
-->
<context:component-scan base-package="com.hqz.dao,com.hqz.service"/>
<!-- 示例 1
use-default-filters="false",示意当初不应用默认 filter,本人配置 filter
context:include-filter,设置扫描哪些内容
-->
<context:component-scan base-package="com.hqz" use-default-filters="false">
<context:include-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
<!-- 示例 2
设置哪些内容不扫描
-->
<context:component-scan base-package="com.hqz">
<context:exclude-filter type="annotation" expression="org.springframework.stereotype.Controller"/>
</context:component-scan>
</beans>
注解阐明
- @AutoWired:依据属性类型进行主动拆卸
@Service
public class UserService {
@Autowired
private UserDao userDao;
public void add() {userDao.add();
}
}
- @Qualifier:依据属性名称进行注入(比方有多个实现类的接口)
@Service
public class UserService {
@Autowired
@Qualifier(value = "userDaoImpl")
private UserDao userDao;
public void add() {userDao.add();
}
}
- @Resource:能够依据类型注入,也能够依据名称注入
@Service
public class UserService {
@Resource
private UserDao userDao;
public void add() {userDao.add();
}
}
- @Value:注入一般类型属性
public class Book {@Value("《金瓶梅》")
private String bookName;
}
齐全注解开发
- 创立配置类,代替 xml 配置文件
// 作为配置类,代替 xml
@Configuration
@ComponentScan(basePackages = {"com.hqz"})
public class SpringConfig {}
- 应用
ApplicationContext applicationContext = new AnnotationConfigApplicationContext(SpringConfig.class);
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