spring注解（创建Bean的对象）
@Controller C: SpringMVC框架
@Service M: service
@Repository M: MyBatis/SpringJDBC
@Component JavaBean不属于M或C层，并且需要通过spring创建对象
注意：依赖AOP机制的，引入aop-jar包
1、操作属性 setter 构造方法
基本类型 + API 类 @Value（“”）不需要setter
@Component class Courses1 implements Courses{ @Value("语文") private String name; @Override public String toString() { return "Courses1{" + "name='" + name + '\'' + '}'; } }
2、注意Component后面可以添加id，使用方法和在config配置bean中的id的使用方法相同：
package zj.it.test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import zj.it.entity.Teacher; import zj.it.four_two.Student; import zj.it.twenty_seven.Hello; /** * Created by Jiang on 2019/3/27 */ public class Test { public static void main(String[] args){ ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationConfig.xml"); Couser1 student = (Couser1 ) applicationContext.getBean("stu"); System.out.println(student); } }
3、如果需要使用list和map，可以直接使用@Autowired注解：
@Autowired @Qualifier("one") private Book books;
4、上面代码中的Book是一个接口， @Qualifier("one")调用的是接口的一个实现类（Qualifier用来选择要使用的类），one表示实现类的id。Book类如下：
package zj.it.four_two; import org.springframework.beans.factory.annotation.Value; import org.springframework.stereotype.Component; import org.springframework.stereotype.Service; /** * Created by Jiang on 2019/4/2 */ @Component("book") public interface Book { String setName(); } @Service("one") class Book1 implements Book{ @Value("战争中") private String name; public Book1() { System.out.println("安徒生童话"); } public void setName(String name) { this.name = name; } @Override public String setName() { System.out.println("安徒生童话"); return "你好"; } @Override public String toString() { return "Book1{" + "name='" + name + '\'' + '}'; } } @Service("two") class Book2 implements Book{ @Value("战争中ssssss") private String name; public void setName(String name) { this.name = name; } public Book2() { System.out.println("格林童话"); } @Override public String setName() { System.out.println("格林童话"); return "你好啊"; } @Override public String toString() { return "Book2{" + "name='" + name + '\'' + '}'; } }
5、上述代码测试结果如下：
Student{name='朱江', age=22, book=[Book1{name='战争中'}, Book2{name='战争中ssssss'}], bookMap={one=Book1{name='战争中'}, two=Book2{name='战争中ssssss'}}, coursesList= [Courses1{name='语文'}, Courses1{name='数学'}, Courses1{name='英语'}, Courses1{name='物理'}, Courses1{name='化学'}], books=Book1{name='战争中'}, stringSet=[sssss, sssseweerss], booksLength=[Book1{name='吱吱吱吱1'}, Book2{name='吱吱吱吱2'}, Book1{name='吱吱吱吱3'}, Book2{name='吱吱吱吱4'}], classRooms=ClassRooms{name='一班'}, teachers=Teachers{yid=111111, name='朱江水水水水'}}
6、完整Student类代码如下：
package zj.it.four_two; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.beans.factory.annotation.Value; import org.springframework.stereotype.Component; import zj.it.entity.ClassRoom; import java.util.Arrays; import java.util.List; import java.util.Map; import java.util.Set; /** * Created by Jiang on 2019/4/2 */ @Component("stu") public class Student { @Value("朱江") private String name; @Value("22") private int age; private List<Book> book; private Map<String, Book> bookMap; private List<Courses> coursesList; @Autowired @Qualifier("one") private Book books; private Set<String> stringSet; private Book[] booksLength; private ClassRooms classRooms; private Teachers teachers; public Student() { } @Autowired() public Student(List<Book> book, Map<String, Book> bookMap,Teachers teachers,ClassRooms classRooms,List<Courses> coursesList) { this.book = book; this.bookMap = bookMap; this.teachers = teachers; this.classRooms = classRooms; this.coursesList = coursesList; } public void setBooksLength(Book[] booksLength) { this.booksLength = booksLength; } public void setStringSet(Set<String> stringSet) { this.stringSet = stringSet; } @Override public String toString() { return "Student{" + "name='" + name + '\'' + ", age=" + age + ", book=" + book + ", bookMap=" + bookMap + ", coursesList=" + coursesList + ", books=" + books + ", stringSet=" + stringSet + ", booksLength=" + Arrays.toString(booksLength) + ", classRooms=" + classRooms + ", teachers=" + teachers + '}'; } }
