springboot获取默认配置文件中的配置项

Dear 丶 2022-11-10 14:14 324阅读 0赞

springboot默认的配置文件是application.properties。如何获取里面的配置项的值呢。

默认配置路径是在classpath根目录【resources】下，或者在classpath:/config目录下

application.properties配置文件中有一下两个配置：

local.ip=192.168.1.100
    local.port=8088

### 方式一：在启动类里获取 ###

@SpringBootApplication
    public class MylslApplication {
    
        public static void main(String[] args) {
            ConfigurableApplicationContext context = SpringApplication.run(MylslApplication.class, args);
            System.err.println("local.ip=" + context.getEnvironment().getProperty("local.ip"));
        }
    
    }

输出：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70][]

### 方式二：在类中利用Environment获取 ###

新建一个类如下：

import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.core.env.Environment;
    import org.springframework.stereotype.Component;
    
    @Component
    public class MyConfig {
    
        @Autowired
        private Environment env;
    
        public void show(){
            System.err.println("MyConfig---local.ip=" + env.getProperty("local.ip"));
        }
    }

在启动类里调用下该show()方法，看下打印结果

package com.lsl.mylsl;
    
    import org.springframework.boot.SpringApplication;
    import org.springframework.boot.autoconfigure.SpringBootApplication;
    import org.springframework.context.ConfigurableApplicationContext;
    
    
    @SpringBootApplication
    public class MylslApplication {
    
        public static void main(String[] args) {
            ConfigurableApplicationContext context = SpringApplication.run(MylslApplication.class, args);
            System.err.println("local.ip=" + context.getEnvironment().getProperty("local.ip"));
            context.getBean(MyConfig.class).show();
        }
    
    }

输出结果：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 1][]

### 方式三：在类中利用@Value注解获取，直接赋值给属性 ###

package com.lsl.mylsl;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.core.env.Environment;
    import org.springframework.stereotype.Component;
    
    @Component
    public class MyConfig {
    
        @Autowired
        private Environment env;
    
        @Value("${local.port}")
        private String localPort;
    
        public void show(){
            System.err.println("MyConfig---local.ip=" + env.getProperty("local.ip"));
            System.err.println("MyConfig---local.port=" + env.getProperty("local.port"));
        }
    }

结果输出：

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 2][]

另外，配置文件支持引用配置

>     local.ip=192.168.1.100
>     local.port=8088
>     
>     name=springboot
>     app.name=this name ${name}

package com.lsl.mylsl;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.core.env.Environment;
    import org.springframework.stereotype.Component;
    
    @Component
    public class MyConfig {
    
        @Autowired
        private Environment env;
    
        @Value("${local.port}")
        private String localPort;
    
        public void show(){
            System.err.println("MyConfig---local.ip=" + env.getProperty("local.ip"));
            System.err.println("MyConfig---local.port=" + env.getProperty("local.port"));
            System.err.println("MyConfig---name=" + env.getProperty("name"));
            System.err.println("MyConfig---app.name=" + env.getProperty("app.name"));
        }
    }

输出结果

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 3][]

### 默认配置文件及路径的重新指定 ###

配置文件的名字和路径也是可以修改的，通过命令来重新指定

修改文件名字：--spring.config.name=app.properties

修改路径：--spring.config.location=classpath:/conf/app.properties;file:e:/temp/app.properties

修改路径可以是系统文件的，利用file:/来修改。

**另外也可以通过编程的方式指定配置文件**

比如在classpath：/conf下有个配置文件app.properties

>     myusername=rootroot
>     password=123456
> 
>

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 4][]

写一个配置类，利用@PropertySource注解引入配置文件

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 5][]

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 6][]

如果需要指定多个配置文件，可以在PropertiesConfig加多个@PropertySource注解

也可以利用@PropertySources注解一次指定多个配置文件

@PropertySources（\{@PropertySource("classpath:/conf/app.properties")，@PropertySource("file:/e:/temp/jdbc.properties")\}）

### 方式四：利用注解@ConfigurationProperties(prefix = "ds")获取带前缀的配置项 ###

>     myusername=rootroot
>     password=123456
>     
>     ds.url=http://192.168.1.200:8080/index.html
>     ds.name=LSL

package com.lsl.mylsl;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.boot.context.properties.ConfigurationProperties;
    import org.springframework.core.env.Environment;
    import org.springframework.stereotype.Component;
    
    @Component
    @ConfigurationProperties(prefix = "ds")
    public class MyConfig {
    
        @Autowired
        private Environment env;
    
        @Value("${local.port}")
        private String localPort;
    
        @Value("${myusername}")
        private String myusername;
    
        @Value("${password}")
        private String password;
    
        private String url;
    
        private String name;
    
        public void show(){
            System.err.println("MyConfig---local.ip=" + env.getProperty("local.ip"));
            System.err.println("MyConfig---local.port=" + env.getProperty("local.port"));
            System.err.println("MyConfig---name=" + env.getProperty("name"));
            System.err.println("MyConfig---app.name=" + env.getProperty("app.name"));
            System.err.println("MyConfig---myusername=" + env.getProperty("myusername"));
            System.err.println("MyConfig---password=" + env.getProperty("password"));
            System.err.println("MyConfig---name=" + name + ",url="+url);
        }
    
        public String getUrl() {
            return url;
        }
    
        public void setUrl(String url) {
            this.url = url;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    }

输出结果

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 7][]

对于带前缀的配置项，当然也可以通过上面的方式获取，也可以采用第四种方式获取，属性名必须后配置项后缀名字一致，且注解@ConfigurationProperties(prefix = "ds")配置好前缀，且配置类里有setter\\getter方法，这样才可以。

最后说下，如果获取配置文件中配置项集合

>     yusername=rootroot
>     password=123456
>     
>     ds.url=http://192.168.1.200:8080/index.html
>     ds.name=LSL
>     
>     ds.ports[0]=9000
>     ds.ports[1]=9001
>     ds.ports[2]=9002

package com.lsl.mylsl;
    
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.beans.factory.annotation.Value;
    import org.springframework.boot.context.properties.ConfigurationProperties;
    import org.springframework.core.env.Environment;
    import org.springframework.stereotype.Component;
    
    import java.util.ArrayList;
    import java.util.List;
    
    @Component
    @ConfigurationProperties(prefix = "ds")
    public class MyConfig {
    
        @Autowired
        private Environment env;
    
        @Value("${local.port}")
        private String localPort;
    
        @Value("${myusername}")
        private String myusername;
    
        @Value("${password}")
        private String password;
    
        private String url;
    
        private String name;
        //注入list
        private List<String> ports = new ArrayList<>();
    
        public void show(){
            System.err.println("MyConfig---local.ip=" + env.getProperty("local.ip"));
            System.err.println("MyConfig---local.port=" + env.getProperty("local.port"));
            System.err.println("MyConfig---name=" + env.getProperty("name"));
            System.err.println("MyConfig---app.name=" + env.getProperty("app.name"));
            System.err.println("MyConfig---myusername=" + env.getProperty("myusername"));
            System.err.println("MyConfig---password=" + env.getProperty("password"));
            System.err.println("MyConfig---name=" + name + ",url="+url);
            System.err.println("MyConfig---ports=" + ports );
    
        }
    
        public List<String> getPorts() {
            return ports;
        }
    
        public void setPorts(List<String> ports) {
            this.ports = ports;
        }
    
        public String getUrl() {
            return url;
        }
    
        public void setUrl(String url) {
            this.url = url;
        }
    
        public String getName() {
            return name;
        }
    
        public void setName(String name) {
            this.name = name;
        }
    }

输出结果

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 8][]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70]: /images/20221022/335ed487c83a44b2aa69bb37b0de619a.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 1]: /images/20221022/2868a5b39d264bb98bb0ec4c5c4d41bc.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 2]: /images/20221022/6f24d3c3bef042bcbee09a87c8086cdd.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 3]: https://img-blog.csdnimg.cn/20210319110719537.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA==,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 4]: https://img-blog.csdnimg.cn/2021031915442138.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA==,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 5]: https://img-blog.csdnimg.cn/2021031915450070.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA==,size_16,color_FFFFFF,t_70
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 6]: https://img-blog.csdnimg.cn/202103191546314.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA==,size_16,color_FFFFFF,t_70
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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA_size_16_color_FFFFFF_t_70 8]: https://img-blog.csdnimg.cn/20210319171017927.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L2Roa2xzbA==,size_16,color_FFFFFF,t_70