Spring框架-常见的几种数据类的注入方式-List Map Array Properties 空值等
废话不多说了，上代码直接。
TestEntity.java
1 package entity;
2
3 import java.util.List;
4 import java.util.Map;
5 import java.util.Properties;
6 import java.util.Set;
7
8 public class TestEntity {
9 private String specialCharacter1; // 特殊字符值1
10 private String specialCharacter2; // 特殊字符值2
11 private User innerBean; // JavaBean类型
12 private List<String> list; // List类型
13 private String[] array; // 数组类型
14 private Set<String> set; // Set类型
15 private Map<String, String> map; // Map类型
16 private Properties props; // Properties类型
17 private String emptyValue; // 注入空字符串值
18 private String nullValue = "init value"; // 注入null值
19
20 public void setSpecialCharacter1(String specialCharacter1) {
21 this.specialCharacter1 = specialCharacter1;
22 }
23
24 public void setSpecialCharacter2(String specialCharacter2) {
25 this.specialCharacter2 = specialCharacter2;
26 }
27
28 public void setInnerBean(User user) {
29 this.innerBean = user;
30 }
31
32 public void setList(List<String> list) {
33 this.list = list;
34 }
35
36 public void setArray(String[] array) {
37 this.array = array;
38 }
39
40 public void setSet(Set<String> set) {
41 this.set = set;
42 }
43
44 public void setMap(Map<String, String> map) {
45 this.map = map;
46 }
47
48 public void setProps(Properties props) {
49 this.props = props;
50 }
51
52 public void setEmptyValue(String emptyValue) {
53 this.emptyValue = emptyValue;
54 }
55
56 public void setNullValue(String nullValue) {
57 this.nullValue = nullValue;
58 }
59
60 public void showValue() {
61 System.out.println("特殊字符1：" + this.specialCharacter1);
62 System.out.println("特殊字符2：" + this.specialCharacter2);
63 System.out.println("内部Bean：" + this.innerBean.getUsername());
64 System.out.println("List属性：" + this.list);
65 System.out.println("数组属性[0]：" + this.array[0]);
66 System.out.println("Set属性：" + this.set);
67 System.out.println("Map属性：" + this.map);
68 System.out.println("Properties属性：" + this.props);
69 System.out.println("注入空字符串：[" + this.emptyValue + "]");
70 System.out.println("注入null值：" + this.nullValue);
71 }
72 }
User.java
1 package entity;
2
3 /**
4 * 用户实体类
5 */
6 public class User implements java.io.Serializable {
7 private String username; // 用户名
8
9 // getter & setter
10 public String getUsername() {
11 return username;
12 }
13
14 public void setUsername(String username) {
15 this.username = username;
16 }
17
18 }
applicationContext.xml核心配置文件
1 <?xml version="1.0" encoding="UTF-8"?>
2 <beans xmlns="http://www.springframework.org/schema/beans"
3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
4 xsi:schemaLocation="http://www.springframework.org/schema/beans
5 http://www.springframework.org/schema/beans/spring-beans-3.2.xsd">
6 <bean id="entity" class="entity.TestEntity">
7 <!-- 使用<![CDATA[]]>标记处理XML特 殊字符 -->
8 <property name="specialCharacter1">
9 <value><![CDATA[P&G]]></value>
10 </property>
11 <!-- 把XML特殊字符替换为实体引用 -->
12 <property name="specialCharacter2">
13 <value>P&G</value>
14 </property>
15 <!-- 给内部引用的类进行注入 -->
16 <property name="innerBean">
17 <bean class="entity.User">
18 <property name="username">
19 <value>张三</value>
20 </property>
21 </bean>
22 </property>
23 <!-- 注入List类型 -->
24 <property name="list">
25 <list>
26 <value>足球</value>
27 <value>篮球</value>
28 </list>
29 </property>
30 <!--注入array数组类型 -->
31 <property name="array">
32 <list>
33 <value>男</value>
34 <value>女</value>
35
36 </list>
37 </property>
38
39 <!-- 注入set類型 -->
40 <property name="set">
41 <set>
42 <value>足球</value>
43 <value>篮球</value>
44 </set>
45 </property>
46 <!-- 注入Map类型 -->
47 <property name="map">
48 <map>
49 <entry>
50 <key>
51 <value>foot</value>
52 </key>
53 <value>脚</value>
54 </entry>
55
56 <entry>
57 <key>
58 <value>hand</value>
59 </key>
60 <value>手</value>
61 </entry>
62 </map>
63 </property>
64 <!-- 注入Properties类型 這種屬性是讀取.properties配置文件的 -->
65 <property name="props">
66 <props>
67 <prop key="aaa">呀呀呀</prop>
68 <prop key="bbb">咪咪咪</prop>
69 </props>
70 </property>
71 <!-- 注入空字符串值 什麽都不寫就是注入了空字符串 -->
72 <property name="emptyValue">
73 <value></value>
74 </property>
75 <!-- 注入null值 -->
76 <property name="nullValue">
77 <null />
78 </property>
79
80 </bean>
81 </beans>
测试类：
package test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import entity.TestEntity;
public class Test {
@org.junit.Test
public void test() {
// 使用ApplicationContext接口的实现类ClassPathXmlApplicationContext加载Spring配置文件
ApplicationContext ctx = new ClassPathXmlApplicationContext(
"applicationContext.xml");
TestEntity entity = (TestEntity) ctx.getBean("entity");
entity.showValue();
}
}
运行结果：
特殊字符1：P&G
特殊字符2：P&G
内部Bean：张三
List属性：[足球, 篮球]
数组属性[0]：男
Set属性：[足球, 篮球]
Map属性：{foot=脚, hand=手}
Properties属性：{bbb=咪咪咪, aaa=呀呀呀}
注入空字符串：[]
注入null值：null
