SpringBoot专栏:配置文件注入知识点汇总（第二讲）

今天药忘吃喽~ 2022-04-03 01:28 189阅读 0赞

###                                             配置文件注入案例讲解（知识点汇总） ###

### 配置文件占位符 ###

${random.value}、${random.int}、${random.long} ${random.int(10)}、${random.int[1024,65536]}

### 属性配置占位符 ###

![20181219194453938.png][]

– 可以在配置文件中引用前面配置过的属性（优先级前面配置过的这里都能用）。

– $\{app.name:默认值\}来指定找不到属性时的默认值

### 配置文件加载位置 ###

**spring boot 启动会扫描以下位置的application.properties或者 application.yml文件作为Spring boot的默认配置文件**

– file:./config/

– file:./ – classpath:/config/

– classpath:/

– 以上是按照优先级从高到低的顺序，所有位置的文件都会被加载，高优先级配置内容会覆盖低优先级配置内容。 – 我们也可以通过配置spring.config.location来改变默认配置

###  Spring Configuration 和 Component 区别（精简汇总版） ###

参考：[https://www.toutiao.com/i6636541118316020231/][https_www.toutiao.com_i6636541118316020231]

### 配置文件值注入（各种类型list、map、int、Sting、boolen等） ###

创建实体类：Student

@Component
    @ConfigurationProperties(prefix = "student")
    
    public class Student {
    
        private String lastName;
        private Integer age;
        private Boolean boss;
        private Date birth;
        private Map<String,Object> maps;
        private List<Object> lists;
        private Book  book;
    
        /**
         * 特别注意！！特别注意！！：如果通过前缀的方式注入，一定要有get set 方法
         * @return
         */
    
        @Override
        public String toString() {
            return "Student{" +
                    "lastName='" + lastName + '\'' +
                    ", age=" + age +
                    ", boss=" + boss +
                    ", birth=" + birth +
                    ", maps=" + maps +
                    ", lists=" + lists +
                    ", book=" + book +
                    '}';
        }
    
        public String getLastName() {
            return lastName;
        }
    
        public void setLastName(String lastName) {
            this.lastName = lastName;
        }
    
        public Integer getAge() {
            return age;
        }
    
        public void setAge(Integer age) {
            this.age = age;
        }
    
        public Boolean getBoss() {
            return boss;
        }
    
        public void setBoss(Boolean boss) {
            this.boss = boss;
        }
    
        public Date getBirth() {
            return birth;
        }
    
        public void setBirth(Date birth) {
            this.birth = birth;
        }
    
        public Map<String, Object> getMaps() {
            return maps;
        }
    
        public void setMaps(Map<String, Object> maps) {
            this.maps = maps;
        }
    
        public List<Object> getLists() {
            return lists;
        }
    
        public void setLists(List<Object> lists) {
            this.lists = lists;
        }
    
        public Book getBook() {
            return book;
        }
    
        public void setBook(Book book) {
            this.book = book;
        }
    }

application.properties配置相关属性

student.last-name=你好spring cloud ${random.uuid}
    student.age=${random.int}
    student.birth=2017/12/15
    student.boss=false
    student.maps.k1=mapv1
    student.maps.k2=mapv2
    student.lists=spring boot ,spring cloud ,spring mvc
    student.book.name=${student.hello:hello}_book
    student.book.price=15

运行测试类

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p6aHVhbl8x_size_16_color_FFFFFF_t_70][]

我们可以看到Student已经被注入相关值

同样Teacher类也可以通过@PropertySource(value = \{"classpath:teacher.properties"\})的方式注入

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p6aHVhbl8x_size_16_color_FFFFFF_t_70 1][]

### 源码下载地址： ###

### [https://github.com/shinians/springboot-demos][https_github.com_shinians_springboot-demos] ###

项目springboot-02-config-simple

希望对您有所帮助。

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p6aHVhbl8x_size_16_color_FFFFFF_t_70 2][]

[20181219194453938.png]: /images/20220403/e431416a46254b6f9b0035af8a7c3119.png
[https_www.toutiao.com_i6636541118316020231]: https://www.toutiao.com/i6636541118316020231/
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p6aHVhbl8x_size_16_color_FFFFFF_t_70]: /images/20220403/5334945c5d644a8da8547bd0f9a115d7.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p6aHVhbl8x_size_16_color_FFFFFF_t_70 1]: /images/20220403/a73ca500d013472c8f835181a3f72640.png
[https_github.com_shinians_springboot-demos]: https://github.com/shinians/springboot-demos
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3p6aHVhbl8x_size_16_color_FFFFFF_t_70 2]: /images/20220403/bd6f82f69aab420381e0b132d3bad66b.png