在上一篇文章中，記錄了用springboot實現輸出一個hello world到前臺的程序，本文記錄學習springboot讀取屬性文件中配置信息。

框架屬性文件(application.properties)

創建一個springboot項目，並引入相關依賴，POM文件如下：

 1 <?xml version="1.0" encoding="UTF-8"?>
 2 <project xmlns="http://maven.apache.org/POM/4.0.0" 
 3     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
 4
 
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 
 5             http://maven.apache.org/xsd/maven-4.0.0.xsd">
 6     
 7     <modelVersion>4.0.0</modelVersion>
 8     
 9     <groupId>org.allen.learn</groupId>
10     <artifactId>springboot_propertiesparam</artifactId>
11
 
     <version>0.0.1-SNAPSHOT</version>
12     
13     <packaging>war</packaging>
14     
15     <!-- Inherit defaults from Spring Boot -->
16     <parent>
17         <groupId>org.springframework.boot</groupId>
18         <artifactId>spring-boot-starter-parent</artifactId>
19
 
         <version>2.0.4.RELEASE</version>
20     </parent>
21 
22     <!-- Add typical dependencies for a web application -->
23     <dependencies>
24         <dependency>
25             <groupId>org.springframework.boot</groupId>
26             <artifactId>spring-boot-starter-web</artifactId>
27         </dependency>
28         
29         <dependency>
30             <groupId>org.springframework.boot</groupId>
31             <artifactId>spring-boot-devtools</artifactId>
32             <optional>true</optional>
33         </dependency>
34         
35     </dependencies>
36     
37 </project>

在resources路徑下創建application.properties文件，並寫入我們的屬性名稱和值，內容如：

allen.properties.type=springboot
allen.properties.title=springboot獲取屬性文件值

寫一個class來接收屬性文件中的值，代碼如下：

 1 package org.allen.learn.property;
 2 
 3 import org.springframework.boot.context.properties.ConfigurationProperties;
 4 import org.springframework.stereotype.Component;
 5 
 6 @Component
 7 @ConfigurationProperties(prefix="allen.properties")//指定前綴是allen.properties
 8 public class PropertiesConfig {
 9     
10     public String type;
11     
12     public String title;
13 
14     public String getType() {
15         return type;
16     }
17 
18     public void setType(String type) {
19         this.type = type;
20     }
21 
22     public String getTitle() {
23         return title;
24     }
25 
26     public void setTitle(String title) {
27         this.title = title;
28     }
29 
30 }

在controller使用我們上邊類中接收到的屬性文件中的值，代碼：

 1 package org.allen.learn.controller;
 2 
 3 import java.io.UnsupportedEncodingException;
 4 import java.util.HashMap;
 5 import java.util.Map;
 6 
 7 import org.allen.learn.property.PropertiesConfig;
 8 import org.springframework.beans.factory.annotation.Autowired;
 9 import org.springframework.web.bind.annotation.RequestMapping;
10 import org.springframework.web.bind.annotation.RestController;
11 
12 @RestController
13 public class PropertiesController {
14     
15     @Autowired
16     private PropertiesConfig propertiesConfig;
17 
18     @RequestMapping("/c1")
19     public String getProperties1() {
20         Map<String, Object> map = new HashMap<String, Object>();
21         map.put("屬性type", propertiesConfig.getType());
22         try {
23             //application.properties 默認編碼格式iso-8859-1，此處中文轉碼
24             map.put("屬性title", new String(propertiesConfig.getTitle().getBytes("iso-8859-1"), "utf-8"));
25         } catch (UnsupportedEncodingException e) {
26             e.printStackTrace();
27         }
28         return map.toString();
29     }
30     
31 }

啟動項目，在瀏覽器中請求 http://localhost:8080/c1

在頁面上可以看到我們在屬性文件中默認給的值。這種取值方式我們需要創建一個類來關聯值，還有一中方法就是使用@Value來獲取屬性文件中的值，代碼：

 1 package org.allen.learn.controller;
 2 
 3 import java.io.UnsupportedEncodingException;
 4 import java.util.HashMap;
 5 import java.util.Map;
 6 
 7 import org.springframework.beans.factory.annotation.Value;
 8 import org.springframework.web.bind.annotation.RequestMapping;
 9 import org.springframework.web.bind.annotation.RestController;
10 
11 @RestController
12 public class ValueController {
13 
14     @Value("${allen.properties.type}")//指定取值屬性名
15     private String type;
16     @Value("${allen.properties.title}")
17     private String title;
18     
19     @RequestMapping("/c2")
20     public String getProperties1() {
21         Map<String, Object> map = new HashMap<String, Object>();
22         map.put("value獲取屬性type", type);
23         try {
24             //application.properties 默認編碼格式iso-8859-1，此處中文轉碼
25             map.put("value獲取屬性title", new String(title.getBytes("iso-8859-1"), "utf-8"));
26         } catch (UnsupportedEncodingException e) {
27             e.printStackTrace();
28         }
29         return map.toString();
30     }
31     
32 }

啟動項目，在瀏覽器中請求 http://localhost:8080/c2 可以在瀏覽器中看到

自定義屬性文件

在resources路徑下創建一個myjdbc.properties文件，並寫入內容，代碼如：

myjdbc.username=root
myjdbc.password=123456

編寫一個class來接收屬性，代碼：

 1 package org.allen.learn.property;
 2 
 3 import org.springframework.boot.context.properties.ConfigurationProperties;
 4 import org.springframework.context.annotation.PropertySource;
 5 import org.springframework.stereotype.Component;
 6 
 7 @Component
 8 @PropertySource(value="classpath:myjdbc.properties")//指定自定義屬性文件
 9 @ConfigurationProperties(prefix="myjdbc")//前綴
10 public class MyJdbcProperties {
11 
12     private String username;
13     
14     private String password;
15 
16     public String getUsername() {
17         return username;
18     }
19 
20     public void setUsername(String username) {
21         this.username = username;
22     }
23 
24     public String getPassword() {
25         return password;
26     }
27 
28     public void setPassword(String password) {
29         this.password = password;
30     }
31     
32     
33 }

創建一個controller來獲取值，代碼：

 1 package org.allen.learn.controller;
 2 
 3 import java.util.HashMap;
 4 import java.util.Map;
 5 
 6 import org.allen.learn.property.MyJdbcProperties;
 7 import org.springframework.beans.factory.annotation.Autowired;
 8 import org.springframework.web.bind.annotation.RequestMapping;
 9 import org.springframework.web.bind.annotation.RestController;
10 
11 @RestController
12 public class MyPropertiesController {
13     
14     @Autowired
15     private MyJdbcProperties myJdbcProperties;
16 
17     @RequestMapping("/c3")
18     public String getMyProperties() {
19         Map<String, Object> map = new HashMap<String, Object>();
20         map.put("myUsername", myJdbcProperties.getUsername());
21         map.put("myPassword", myJdbcProperties.getPassword());
22         return map.toString();
23     }
24     
25 }

啟動項目，在瀏覽器中輸入請求地址 http://localhost:8080/c3 瀏覽器中會輸出內容：

下載源碼 https://files.cnblogs.com/files/wlzq/springboot_propertiesparam.zip

springboot入門_獲取屬性文件中的值