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How access uploaded file in spring framework

I am new to Spring framework in spring site There is tutorial at https://spring.io/guides/gs/uploading-files/ that upload file to the root folder "upload-dir" (this folder is beside src root folder)
questions:
How can I access and show image in browser (or access it in thymeleaf by th:src="#{}" syntax) -
by browsing to localhost:8080/files/first.jpg because of controller it give me download link.
should I always upload file to folder that beside src folder for example I want to upload file to "src/main/resources/static/file" is it possible?

When accessing files in your code, Spring will (by default) assume that the src/main/resources is the parent directory. If you are planning on accessing the files that are uploaded, then I would use src/main/resources (or a subdirectory of this location) as the upload path. This way, you can simply access them in Thymeleaf as such:
Location: src/main/resources/picture.jpg
Thymeleaf: th:src="#{picture.jpg}"
Or if the file exists in a subdirectory:
Location: src/main/resources/somedir/picture.jpg
Thymeleaf: th:src="#{somedir/picture.jpg}"
If you are storing the file(s) elsewhere, then you can also access them using various prefixes like classpath or file, i.e.:
classpath:com/myapp/config.xml
See more about Resources in Spring here:
http://docs.spring.io/spring/docs/current/spring-framework-reference/html/resources.html
Hope this helps!

Read common external property file in Java Webapp and java normal app

I know this question has answered many a time with most useful answer as below,
Where to place and how to read configuration resource files in servlet based application?
However, We have some special requirement as below,
Webapp will be deployed to tomcat.
Normal java app in form of .jar will be placed under folder /myapp
myappConfig.property file will be placed under /myapp
Directory Structure on client machine
/myapp
/myapp.jar
/assests/myappConfig.property
/tomcat/webapps/myapp.war
Basically myapp.jar and myapp.war will access sql db connection values for MySql database connection and db operations.
Accessing myappConfig.property from myapp.jar --> Working fine
File jarPath = new File(Myapp.class.getProtectionDomain().getCodeSource().getLocation().getPath());
String propertiesPath = jarPath.getParent();
System.out.println(" propertiesPath-" + propertiesPath);
mainProperties.load(new FileInputStream(propertiesPath + "\\assets\\myapp.property"));
Can anyone help/suggest how to implement,
Accessing myappConfig.property file from mywebapp,
provided run time change in myappConfig.property file does not required myapp.war to be redeployed
Thanks for your help in advance.
edit
Below is the steps in which we want to deliver the project to client.
Below is my app directory
/myapp
/myapp.jar
/assests/myappConfig.property
/tomcat/webapps/myapp.war
pack everything in one package with some packaging tool.
Run this package in client machine at any location and it will have same directory structure as above
Here, I do not want to hard code any location in webapp or tomcat for "/assests/myappConfig.property"
Normal Java app I can read property file but for wepapp I am not getting clear idea for how to do that?

You can add a <context> to tomcat/conf/server.xml (in this example, linux path):
<Context docBase="/home/yourusername/tomcat/assests" path="/assets" />
If you are using Windows:
<Context docBase="C:\path\to\myapp\assets" path="/assets" />
And then you can access it like any other resource within your webapp (e.g.: /assets/myappConfig.property).
If you are using JDBC for example, you could store the connection properties in a Singleton and request it from there, and that class could take care of change checks on that file.

Why doesn't tomcat see certain folders?

In my tomcat webapps directory I have various projects with servlets in them ..
say named test,beer etc
My question is irrespective of the web.xml or contents when i type localhost:8080/folderName I must be able to view the contents right? but it doesnt work for all folders , for some it says resource not found ,
Example my test folder opens in the browser and my beer folder doesnt , I restarted the browser and tomcat after adding or modifying folders , why can this happen , please explain

My dear friend there is a certain process/configuration/rule that tomcat follows in order to render any web content.It is not some magic happening.
Tomcat has a way of reading web deployments within the /webapp directory.
When we type some URL On the browser tomcat does the following:
Example.
URL : http://localhost:8080/foldername/xyz
Here tomcat takes the part of the URL after http://localhost:8080,that is foldername/xyz.
So here the first part which is foldername means name of the folder present in the /webapps folder.
So reading this tomcat goes inside that folder.Later tomcat is at the mercy of a file called web.xml.All mapping from /foldername/ i.e. /xyz in our case, onwards are present in web.xml.
In your case , if you type http://localhost:8080/foldername/ , tomcat knows that browser refers to webapps/foldername but does not know which resource html/jsp/servlet to forward the request so as to be able to generate a response.
Hence it gives a resource not found exception.
If you want to run the above URL (http://localhost:8080/foldername) then you need to configure a <welcome-file-list> tag in the web.xml file.
So for the folders which are working in your case with the above URL, just open their web.xml file and you shall find the <welcome-file-list> tag.

Actually this is what happened
I had a folder test which had some files (NO WEB-INF) , tomcat listed its contents on typing localhost:8080/test
My other folder beer had a WRONG WEB-INF web.xml configuration
So the following is clear to me now
Without a WEB-INF folder and web.xml tomcat will just list the contents of the directory but when you have a WEB-INF and web.xml and something is wrong in them it doesnt even list the directory contents .
Just my understanding of it .
Thanks!

cant read files from resources

Im trying to read files(xml, images) from src/main/resources. But it doesnt work.My resources folder is Source folder. For example, when i m trying to read log4j.xml tomcat looking for it in C:/bin... And i also cant read images from resources. I can read it only from webapp. I ve read, that tomcat automatically replace files from resources to webinf, but i think that it doesnt work in my case.
Please, help. I dont have any idea.

Even if the png is added to the WEB-INF folder it wouldn't be accessible from the JSP page in your case.
On runtime a JSP page renders into a servlet that return HTML code in the response. Then a browser will parse your tag <img src="/Pajero.png" ... /> and send a request onto YOUR_HOST/Pajero.png url to access the image and get the error code 404, because content of the WEB-INF folder is not accessible for a client side in a java web application.
Perhaps it will be better to place images on the webapp folder at your case.

ClassLoader classLoader = getClass().getClassLoader();
File file = new File(classLoader.getResource("log4j.xml").getFile());
You can use something like this to get resources from classpath.
Regards

Servlet/Tomcat relative file path

Where to put files in a Tomcat Servlet application, such that they are relatively visible to the page??
More detail:
I am developing a servlet page while using an external library. That library depends massively on external loaded XML files (relative file paths). So I need to put these XML files in the running directory of the servlet.
Is there a way in Tomcat server, where files can be accessible relatively?

When a web application is deployed to Tomcat, the root of the web application ends up being $CATALINA_HOME/webapps/YOUR_WEB_APP/
As such, if using a servlet to access an XML file located on a path within the root of your web application, you can just use the following:
request.getServletContext().getResourceAsStream("PATH/TO/YOUR/XML_FILE.xml")
This will load the XML file as an InputStream. Of course, if you want access to the file itself, you can always use the getResource(String resource) method to obtain a URL, from which a File object can be obtained like so (alternative methods included):
File f;
try {
f = new File(url.toURI());
} catch(URISyntaxException e) {
f = new File(url.getPath());
}
EDIT: To make them relatively visible to a web browser, simply keep them out of the ./WEB-INF and ./META-INF directories.

If this library you are talking about is going to search for the file on the classpath (like Hibernate or Log4J would do), you will have to put your XML file in WEB-INF. However, I suggest you do not do this manually. You can put the file in a source directory of you application, which will make sure the file gets deployed on the right spot.

This is an old question. I'm working on Tomcat 9. I've been quite successful with taking the Tomcat installation directory as the base. (CATALINA_HOME) The relative path to a file in ROOT for example is then, "webapps/ROOT/someDir/fileName"
The place to complain about repeated answers is to deal with repeated questions.