Unable to load image in browser in spring boot project using Intellij-CodePudding

I created a spring boot project to use Jfree chart API.

When I am trying to load my db data as pie chart in browser, pie chart is not loading.

Project Structure:

I created locationReport.html under templates folder to display the jpeg image.

locationReport.html:

<!DOCTYPE html>
<html lang="en" xmlns:th="http://www.thymeleaf.org">
<head>
    <meta charset="UTF-8">
    <title>Location Report</title>
</head>
<body>
<img src="location.jpeg" alt="Error in location image">
</body>
</html>

Controller:

@Controller
@RequestMapping("/api/v1/")
public class LocationController {
    @RequestMapping(value = "/generateReport")
    public String generateLocationReport() throws IOException {
    locationService.generateLocationReport();
        return "locationReport";
    }
}

LocationServiceImpl:

 @autowired
 private ServletContext servletContext;
    @Override
    public void generateLocationReport() throws IOException {
        String path = servletContext.getRealPath("/");
        List<Object[]> data = locationRepository.findTypeAndTypeCount();
        reportUtil.generatePieChart(path, data);

LocationRepository

    @Query(value="SELECT loc.type, COUNT(loc) FROM Location loc GROUP BY loc.type")
    List<Object[]> findTypeAndTypeCount();

ReportUtil:

    @Override
    public void generatePieChart(String path, List<Object[]> data) throws IOException {
        DefaultPieDataset dataset = new DefaultPieDataset();
        for (Object[] object : data) {
            dataset.setValue(object[0].toString(), Double.valueOf(object[1].toString()));
        }

       JFreeChart locationChart = ChartFactory.createPieChart3D("Location Report", dataset);

        ChartUtils.saveChartAsJPEG(new File(path "/location.jpeg"),locationChart,300,300);
    }

Image is successfully created at root directory (inside webapp) but its not loading in browser.

Note - I have added thymeleaf dependency and other functionalities working expectedly

CodePudding user response：

By default spring will load static resources from

/META-INF/resources/
/resources/
/static/
/public/

but in this case you're generating the pie chart image, you will to config ResourceHandler to let your server read and serve those generated-images.

@Configuration
@EnableWebMvc
public class Config implements WebMvcConfigurer {
    @Override
    public void addResourceHandlers(ResourceHandlerRegistry registry) {
        registry
                .addResourceHandler("/generated-images/**")
                .addResourceLocations("file:generated-images/");
    }
}

this example config will enable your application read from the project_root/generated-images folder when users access http://generated-images/image_name.jpeg

CodePudding user response：

I was using @RequestMapping("/api/v1/") at class level. When i removed it, it worked expectedly.

@Controller
@RequestMapping("/api/v1/") <--Removed it
public class LocationController {

    @RequestMapping(value = "/generateReport")
    public String generateLocationReport() throws IOException {
    locationService.generateLocationReport();
        return "locationReport";
    }
}