Spring之三種依賴注入，給各種集合型別的屬性注入值
阿新 • • 發佈：2021-01-07
技術標籤：java
、第一種注入（set注入）：
建立實體類,Teacher:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
package org.ruangong.entity;
public class Teacher {
private String name; private int age; public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; }
}
建立實體類，Course:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
package org.ruangong.entity;
public class Course {
private String cname; private int chour; private Teacher teacher; public String getCname() { return cname; } public void setCname(String cname) { this.cname = cname; } public int getChour() { return chour; } public void setChour(int chour) { this.chour = chour; } public Teacher getTeacher() { return teacher; } public void setTeacher(Teacher teacher) { this.teacher = teacher; } @Override public String toString() { return "Course [cname=" + cname + ", chour=" + chour + ", teacher=" + teacher.getName() + teacher.getAge()+"]"; }
}
在applicationContext.xml檔案中新增bean標籤。
1
2
3
4
5
6
7
8
9
10
<property name="name" value="王建民"></property> <property name="age" value="50"></property> </bean> <bean id="course" class="org.ruangong.entity.Course"> <property name="cname" value="java"></property> <property name="chour" value="2"></property> <property name="teacher" ref="teacher"></property> </bean>
其中的ref=“”，對應物件值。將teacher物件注入到course物件中。
二、第二中注入(構造器注入)：
在Teacher實體中新增構造方法。
1
2
3
4
5
public Teacher(String name, int age) {
super();
this.name = name;
this.age = age;
}
在Course實體中新增構造方法：
1
2
3
4
5
6
public Course(String cname, int chour, Teacher teacher) {
super();
this.cname = cname;
this.chour = chour;
this.teacher = teacher;
}
在之前的applicationContext.xml檔案的id為teacher和course標籤重新新增構造方法。
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
<!-- 通過set注入 -->
<!-- <property name="name" value="王建民"></property>
<property name="age" value="50"></property> -->
<!-- 通過構造器注入 -->
<constructor-arg value="劉丹"></constructor-arg>
<constructor-arg value="48"></constructor-arg>
</bean>
<bean id="course" class="org.ruangong.entity.Course">
<!-- 通過set注入 -->
<!-- <property name="cname" value="java"></property>
<property name="chour" value="2"></property>
<property name="teacher" ref="teacher"></property> -->
<!-- 通過構造器注入 -->
<constructor-arg value="PHP"></constructor-arg>
<constructor-arg value="5"></constructor-arg>
<constructor-arg ref="teacher"></constructor-arg>
</bean>
或者可以在constructor標籤的後面新增index=“key”,key值來控制屬性順序。
或者新增name=“key”，key來控制屬性名。
三、第三種注入（P值注入）
生成P的標籤。
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
<!-- 通過set注入 -->
<!-- <property name="name" value="王建民"></property>
<property name="age" value="50"></property> -->
<!-- 通過構造器注入 -->
<!-- <constructor-arg value="劉丹"></constructor-arg>
<constructor-arg value="48"></constructor-arg> -->
</bean>
<bean id="course" class="org.ruangong.entity.Course" p:cname="統一建模" p:chour="6" p:teacher-ref="teacher">
<!-- 通過set注入 -->
<!-- <property name="cname" value="java"></property>
<property name="chour" value="2"></property>
<property name="teacher" ref="teacher"></property> -->
<!-- 通過構造器注入 -->
<!-- <constructor-arg value="PHP"></constructor-arg>
<constructor-arg value="5"></constructor-arg>
<constructor-arg ref="teacher"></constructor-arg> -->
</bean>
四、集合型別值注入：
建立集合實體，AllCollectionType:
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
package org.ruangong.entity;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import java.util.Set;
public class AllCollectionType {
private List<String> list;
private String[] array;
private Map<String,String> map;
private Set<String> set;
private Properties props;
public List<String> getList() {
return list;
}
public void setList(List<String> list) {
this.list = list;
}
public String[] getArray() {
return array;
}
public void setArray(String[] array) {
this.array = array;
}
public Map<String, String> getMap() {
return map;
}
public void setMap(Map<String, String> map) {
this.map = map;
}
public Set<String> getSet() {
return set;
}
public void setSet(Set<String> set) {
this.set = set;
}
public Properties getProps() {
return props;
}
public void setProps(Properties props) {
this.props = props;
}
@Override
public String toString() {
return "AllCollectionType [list=" + list + ", array=" + Arrays.toString(array) + ", map=" + map + ", set=" + set
+ ", props=" + props + "]";
}
}
在applicationContext.xml檔案中：
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
<!-- 通過set方式賦值 -->
<property name="list">
<list>
<value>[體育新聞](http://www.snmky.org/tiyu/)</value>
<value>足球</value>
<value>乒乓球</value>
</list>
</property>
<property name="array">
<array>
<value>籃球_array</value>
<value>[足球比分](http://www.snmky.org/zqbf/)_array</value>
<value>乒乓球_array</value>
</array>
</property>
<property name="map">
<map>
<entry>
<key>
<value>
foot
</value>
</key>
<value>足球</value>
</entry>
<entry>
<key>
<value>
basket
</value>
</key>
<value>**[nba直播吧](http://www.snmky.org/gov/)**</value>
</entry>
<entry>
<key>
<value>
pingpang
</value>
</key>
<value>足球</value>
</entry>
</map>
</property>
<property name="set">
<set>
<value>籃球_set</value>
<value>足球_set</value>
<value>乒乓球_set</value>
</set>
</property>
<property name="props">
<props>
<prop key="foot4">足球</prop>
<prop key="basket4">籃球</prop>
<prop key="pp4">乒乓球</prop>
</props>
</property>
</bean>
test中進行測試：
1
2
3
4
5
public static void collectionDemo(){
ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
AllCollectionType type = (AllCollectionType)context.getBean("collection");
System.out.println(type);
}