Spring boot，无法读取文件，启动时使用jar包

Question

Spring boot, The file can not be read, Use jar package when starting. When I use the .war start the way everything is normal

This is war maven pom.xml

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-resources-plugin</artifactId>
    <version>2.6</version>
    <configuration>
        <nonFilteredFileExtensions>
            <nonFilteredFileExtension>xls</nonFilteredFileExtension>
            <nonFilteredFileExtension>xlsx</nonFilteredFileExtension>
            <nonFilteredFileExtension>p12</nonFilteredFileExtension>
        </nonFilteredFileExtensions>
    </configuration>
</plugin>

But use java -jar

I want to start with java -jar, Now what do I need to do? spring boot version 1.4.4

public void generater(HttpServletResponse response, boolean testMode) {
        ExcelTemplateEnum excelTemplate = this.exportTemplate();
        FileInputStream is = null;
        Workbook workbook = null;
        try {
            String templateFilePath = this.getTemplateFilePath(excelTemplate);
            URL url = ExeclExportHandler.class.getClassLoader().getResource(templateFilePath);
            is = new FileInputStream(url.getFile());
            ExcelTransformer transformer = this.getExcelTransformer();
            // 渲染导出数据
            if (isMultipleBeans()) {
                List<Map<String, Object>> data = this.renderDataList();
                this.checkExportParam(data);
                workbook = transformer.transform(is, getTemplateSheetNamesList(), getSheetNamesList(), data);
            } else {
                Map<String, Object> data = this.renderData();
                this.checkExportParam(data);
                workbook = transformer.transform(is, data);
            }
            if (testMode) {
                ...
            } else {
                ExcelHelper.setExcelHeader(response, excelTemplate.outname());
                workbook.write(response.getOutputStream());
                response.flushBuffer();
            }
        } catch (Exception e) {
            ...
        } finally {
            IOUtils.closeQuietly(is, workbook);
        }
    }

error line 75

    is = new FileInputStream(url.getFile());

Answer 1

You have to access the resource by Class.getResourceAsStream() , since you can't access files packed in a jar:

is = this.getClass().getResourceAsStream(templateFilePath)

If it works with a war it is just luck, since your servlet/J2EE-container seems to unpack your war... which is not the case with all containers (due to the spec it is up to the container whether it will unpack the the war or not). Means with a different container you will get also get this Exception with the war.