导出报错cannot be resolved to absolute file path because it does not reside in the file system

SpringBoot项目打包部署，读取jar里面的文件报错500，异常日志关键提示

cannot be resolved to absolute file path because it does not reside in the file system

报错定位

 is = new FileInputStream(ResourceUtils.getFile("classpath:static/data_template/biz/export_XXXX_report.xlsx"));

从报错可看到读取文件路径XXX.jar!**.xlsx，XXX.jar就是打成jar，里面包含了需要读取的模板文件

具体Spring core(版本5.2.12)包源码ResourceUtils

public static File getFile(URL resourceUrl, String description) throws FileNotFoundException {
		Assert.notNull(resourceUrl, "Resource URL must not be null");
		if (!URL_PROTOCOL_FILE.equals(resourceUrl.getProtocol())) {
            //报错所在地方
			throw new FileNotFoundException(
					description + " cannot be resolved to absolute file path " +
					"because it does not reside in the file system: " + resourceUrl);
		}
		try {
			return new File(toURI(resourceUrl).getSchemeSpecificPart());
		}
		catch (URISyntaxException ex) {
			// Fallback for URLs that are not valid URIs (should hardly ever happen).
			return new File(resourceUrl.getFile());
		}
	}

解决办法如下：

//获得文件流时，因为读取的文件是在打好jar文件里面，不能直接通过文件资源路径拿到文件，但是可以在jar包中拿到文件流
//ResourcePatternResolver的实现方法，可以匹配到各种部署时的各种文件类型例如war，jar，zip等等findPathMatchingResources
ResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
Resource[] resources = resolver.getResources("static/data_template/biz/XXXX.xlsx");
Resource resource = resources[0];
InputStream  is = resource.getInputStream();

Spring源码（PathMatchingResourcePatternResolver）关键代码段

@Override
	public Resource[] getResources(String locationPattern) throws IOException {
		Assert.notNull(locationPattern, "Location pattern must not be null");
		if (locationPattern.startsWith(CLASSPATH_ALL_URL_PREFIX)) {
			// a class path resource (multiple resources for same name possible)
			if (getPathMatcher().isPattern(locationPattern.substring(CLASSPATH_ALL_URL_PREFIX.length()))) {
				// a class path resource pattern
				return findPathMatchingResources(locationPattern);
			}
			else {
				// all class path resources with the given name
				return findAllClassPathResources(locationPattern.substring(CLASSPATH_ALL_URL_PREFIX.length()));
			}
		}
		else {
			// Generally only look for a pattern after a prefix here,
			// and on Tomcat only after the "*/" separator for its "war:" protocol.
			int prefixEnd = (locationPattern.startsWith("war:") ? locationPattern.indexOf("*/") + 1 :
					locationPattern.indexOf(':') + 1);
			if (getPathMatcher().isPattern(locationPattern.substring(prefixEnd))) {
				// a file pattern
				return findPathMatchingResources(locationPattern);
			}
			else {
				// a single resource with the given name
				return new Resource[] {getResourceLoader().getResource(locationPattern)};
			}
		}
	}

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