Springboot2.x——Jar运行静态资源报错问题

Springboot打成Jar包运行，和在Idea内启动读取资源文件的方法是不一样的，导致部署项目的时候出了点问题

一、编译器内直接springboot项目运行：

properties去读数据：

public class GetProUtil {
   private String file;
   private Properties prop;
   
   public GetProUtil(String file) {
      this.file = file;
      this.prop = readProperties();
   }
   
   private Properties readProperties(){
      Properties properties = new Properties();
      InputStream inputStream;
      try {
         inputStream = new FileInputStream(file);
         BufferedReader bf = new BufferedReader(new InputStreamReader(inputStream, "utf-8"));
         properties.load(bf);
         inputStream.close(); // 关闭流
      } catch (Exception e) {
         throw new RuntimeException(e.getMessage());
      }
      return properties;
   }
}

方法调用可行

public static GetProUtil iot = new GetProUtil("src/main/resources/iot.properties");

二、springboot打成jar包去运行：

报错如下：无法找到该路径文件

Caused by: java.lang.RuntimeException: src/main/resources/iot.properties (No such file or directory)
at com.wx.utils.GetProUtil.readProperties(GetProUtil.java:56)
at com.wx.utils.GetProUtil.(GetProUtil.java:37)
at com.wx.mqtt.WxVariable.(WxVariable.java:8)
... 13 more

将读取路径修改成流：

private Properties readProperties(){
   Properties properties = new Properties();
   InputStream inputStream;
   try {
      //inputStream = new FileInputStream(file);
      
      ClassPathResource resource = new ClassPathResource(file);
      inputStream = resource.getInputStream();
      
      File resourceFile = resource.getFile();
      //BufferedReader bf = new BufferedReader(new InputStreamReader(new FileInputStream(resourceFile)));
      //String msg = reader.readLine();
      
      BufferedReader bf = new BufferedReader(new InputStreamReader(inputStream, "utf-8"));
      properties.load(bf);
      inputStream.close(); // 关闭流
   } catch (Exception e) {
      throw new RuntimeException(e.getMessage());
   }
   return properties;
}

调用方法修改成：

public static GetProUtil iot = new GetProUtil("iot.properties");

springboot jar 运行报错：路径：/Users/wuxi/RunJar/springboot-mqtt-0.0.1-SNAPSHOT.jar!/BOOT-INF/classes!/iot.properties

Caused by: java.lang.RuntimeException: class path resource [iot.properties] cannot be resolved to absolute file path because it does not reside in the file system: jar:file:/Users/wuxi/RunJar/springboot-mqtt-0.0.1-SNAPSHOT.jar!/BOOT-INF/classes!/iot.properties
at com.wx.utils.GetProUtil.readProperties(GetProUtil.java:59)
at com.wx.utils.GetProUtil.(GetProUtil.java:28)
at com.wx.mqtt.WxVariable.(WxVariable.java:9)
... 13 more

发现该行代码报错：

File sourceFile = resource.getFile();

macos linux系统下面 需要使用

ClassPathResource resource = new ClassPathResource(file);
inputStream = resource.getInputStream();

注释掉再次运行OK

方便使用：直接定义两种获取方式

private Properties readProperties(){
   Properties properties = new Properties();
   InputStream inputStream;
   try {
      if (file.contains("src")) {
         inputStream = new FileInputStream(file);
      }else {
         ClassPathResource resource = new ClassPathResource(file);
         inputStream = resource.getInputStream();
      }
      BufferedReader bf = new BufferedReader(new InputStreamReader(inputStream, "utf-8"));
      properties.load(bf);
      inputStream.close(); // 关闭流
   } catch (Exception e) {
      throw new RuntimeException(e.getMessage());
   }
   return properties;
}