英文:
Problem with loading a third party jar inside a spring boot application
问题
我正在创建一个Spring Boot应用程序，出于业务原因，我需要导入一个第三方jar包，该包还从名为application.properties的文件中读取一些配置参数。
我已经在Spring Boot的application.properties文件中定义了我应用程序和第三方jar包所需的所有配置。
当我从Eclipse运行此应用程序时，一切正常，但当我尝试使用命令从外部运行它时，jar包内部的代码找不到application.properties文件并抛出异常；
java -jar myapp.jar
当我将命令更改为以下命令，并将application.properties文件放在jar包外部时，它可以正常工作；
java -Xbootclasspath/a: -jar myapp.jar
如何在不将application.properties文件放在jar包外部的情况下使其正常工作？
一些额外的信息；
第三方jar是作为我的Maven依赖项包含的库jar。在第三方代码内部，有一个地方它正在加载application.properties文件，但是会抛出异常。
Properties cfg = new Properties();
FileInputStream is = null;
URL url = DemoApplication.class.getResource("/");
if (null != url) {
String configPath = url.getFile() + "application.properties";
try {
is = new FileInputStream(configPath);
cfg.load(is); // 加载失败在这里
} catch (IOException e) {
e.printStackTrace();
}
}
异常：
file:/D:/Temp/target/myapp.jar!/BOOT-INF/classes!/application.properties 加载配置失败 java.io.FileNotFoundException: file:\D:\Temp\target\myapp.jar!\BOOT-INF\classes!\application.properties（文件名、目录名或卷标语法不正确）
英文:
I am creating a Spring Boot application, for a business reason I need to import a 3rd party jar which also reads some config parameter from a file named application.properties.
I have defined all the configs required by my app and the 3rd party jar in the spring boot application.properties file.
When I run this application from Eclipse all is well, but when I run it from outside by using command the code inside the jar can't find the application.properties file and throws exception;
java -jar myapp.jar
when I change it to following command and by placing the application.properties file outside the jar it works;
java -Xbootclasspath/a: -jar myapp.jar
How can make it work without placing the application.properties file from outside the jar?
Some additional Info;
3rd party jar is a lib jar included as my maven dependency. Inside the 3rd Party code there is a place where it's loading application.properties file, but throws exception.
Properties cfg = new Properties();
FileInputStream is = null;
URL url = DemoApplication.class.getResource("/");
if (null != url) {
String configPath = url.getFile()+ "application.properties";
try {
is = new FileInputStream(configPath);
cfg.load(is); // It fails here
} catch (IOException e) {
e.printStackTrace();
}
}
Exception:
file:/D:/Temp/target/myapp.jar!/BOOT-INF/classes!/application.properties FAILED load config.java.io.FileNotFoundException: file:\D:\Temp\target\myapp.jar!\BOOT-INF\classes!\application.properties (The filename, directory name, or volume label syntax is incorrect)
答案1
得分: 0
如果这是一个Maven项目，请尝试使用（mvn package）命令，然后在目标文件夹下运行生成的jar文件。
英文:
If it's a maven project, try to use (mvn package) command and then run the jar generated under the target folder
答案2
得分: 0
如果你的第三方应用是我App的Maven依赖，你可以从类路径中加载它：
Properties cfg = new Properties();
cfg.load(DemoApplication.class.getClassLoader().getResourceAsStream("application.properties"));
英文:
If your thirdparty-app is a maven dependency of myApp you can load it from the classpath:
Properties cfg = new Properties();
cfg.load(DemoApplication.class.getClassLoader().getResourceAsStream("application.properties"));
答案3
得分: 0
第三方的 JAR 包使用了一个 FileInputStream，其 URL 是从 Class.getResource(...) 中获取的。
这在处理 JAR 文件时是行不通的。
可以尝试的方法是跳过 FileInputStream，而使用 Class.getResourceAsStream(...)：
InputStream is = DemoApplication.class.getResourceAsStream("/application.properties");
英文:
That 3rd Party jar uses a FileInputStream with a URL that starts with something derived from Class.getResource(...).
That's never going to work with jar files.
What can work is to skip the FileInputStream, but use Class.getResourceAsStream(...):
InputStream is = DemoApplication.class.getResourceAsStream("/application.properties")
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