I am developing a dynamic web project j2ee web application using eclipse. I have an existing jasper report file in .jrxml format found in web-inf/jasperreports folder. How do I access these files from my java classes in the src folder. I am not even sure if context path is the right term for the root folder of the application so please enlighten me too on this part.
I am using by the way spring webflow. how do i get or initialize the object servlet context
ServletContext.getRealPath method can be used to get the context path. ServletContext.getRealPath("/") returns the webapp root path. Path for WEB-INF/jasperreports would be:
ServletContext sc = getServletContext();
String reportPath = sc.getRealPath("/WEB-INF/jasperreports");
You can initialize you java classes from a Servlet of ServletContextListener where you can get reference for ServletContext by respectively the inherited getServletContext() and the servletContextEvent.getServletContext().
Related
I have spring mvc web application which is deployed on a tomcat server. On that project, I want to create folders and files in the runtime. currently I can create folders in the server root by using System.getProperty("catalina.base"). But when I deployed the project in a externel server I cant create folders on the root level of the tomcat server beacuse I don't have permissions. Intead of that I decided to create folders in following directory.
tomcat_dirctory/webapps/myproject_directory
so I need to create folders and files in side the myproject_directory in the runtime. Can anyone tell me what is the path for that. May be I can hardocde that as follows.
System.getProperty("catalina.base") + File.separator + "webapps"+File.separator+"myproject_directory"
But Instead of hard coding I prefer to know is there any alternative way to obtain my project path.
You can use getServletContext().getRealPath("/");
Gets the real path corresponding to the given virtual path.
For example, if path is equal to /index.html, this method will return the absolute file path on the server's filesystem to which a request of the form http://://index.html would be mapped, where corresponds to the context path of this ServletContext.
The real path returned will be in a form appropriate to the computer and operating system on which the servlet container is running, including the proper path separators.
Resources inside the /META-INF/resources directories of JAR files bundled in the application's /WEB-INF/lib directory must be considered only if the container has unpacked them from their containing JAR file, in which case the path to the unpacked location must be returned.
This method returns null if the servlet container is unable to translate the given virtual path to a real path.
Can anyone tell how to access resource file in class library asp.net mvc4? I'm building a generic Class Library that I will use it in all my projects. I tried with following code:
HttpContext.GetGlobalResourceObject();
Can anyone tell any other method is there to access the resource file in class library?
Edit based on the comments, including best practices :
To create a Resource file in MVC4 :
In the solution explorer, right click on your project.
Then, you click on "Add", then on "Add ASP.Net folder", and then click on App_GlobalResources.
On the new folder, you right click. Then you add a new Resource File.
You open then this Resource file and can add new resources.
The lefter column is where you set the keys, and the righter one is for the values you have to insert inside it.
Then; it is really easy, you just have to write the following parts of code to access the values you want.
On the c# side, it is :
Resources.NameOfYourResFile.NameOfYourResKey
On the ASP side, assuming that you're using razor, it is :
#Resources.NameOfYourResFile.NameOfYourResKey
Example :
If you have created a a file named "Global.resx", and created the key "ApplicationTitle", which has "My super website" as value, you just have to write the following line of code to put it for example into a string :
string siteTitle = Resources.Global.ApplicationTitle;
and that's it
When you create your resource you have to set the access level from internal (by default) to public. After this you simply can access your resources (if you reference the assembly) by the name of the resource and the static properties generated into them.
I would suggest you to create a new library for Resources
Once you are done making resources key value pairs then add the reference of your Resource Library in to your project. and then you are able to access the resource library in this way
Namespace.ReourceLibraryName.Key
just include System.Web.dll in your class library project and access the resource file just like you would have accessed in the MVC project
HttpContext.GetGlobalResourceObject();
when you add a refrence to this class library project inside your MVC project and run the project this code will be executed in the context of the MVC project and you will get the correct instance of HttpContext.
Note:- directly using HttpContext like this would create problems when you will try to test this application
You can add your resource file any where in your class library, but I think your question is how to use it, If your resource files name is Res1.resx and there is a key in it called message then you can call
Res1.message
from your classes in that library. But you I am sure you would like to use it event from out side the library for that you need to make your resource file public, please refer Visual Studio - Resx File default 'internal' to 'public'
please do let me know if it is the one you need or some thing else?
How to get current working directory for struts2 web application?
String currentDir = System.getProperty("user.dir");
String currentDir = new File(".").getAbsolutePath();
return /usr/share/tomcat.
I need path to web application, so I could read a file from war.
You need to get the ServletContext's real path: ServletContext.getRealPath(String)
That said, why do you want to read a file that's in a war file, and why do you want to do it this way?
Prefer putting the file on the classpath and using getResourceAsStream:
API
Docs
We use logback and slf4j as logging libraries for our application and glassfish v3 as our application server. For the deployment time configuration properties we have created a "JNDI Custom Resource" in glassfish with the factory class as "org.glassfish.resources.custom.factory.JavaBeanFactory".
Specifying this factory class, glassfish creates an instance of the specified custom java bean (termed as resource type in glassfish) and set the user specified properties in this class instance.
My question is - Is there a way to use one of the properties specified for this java bean in logback? i.e. Is there a way to tell logback (in the tag) to read properties from a java bean?
I intend to add a property in the java bean as the "log location" which I can then use in my logback.xml. This property can be set by the application installer team to configure the location of the log files.
Also since we already have one Custom JNDI resource defined in glassfish we intend to use the same one for all the configuration properties for our application.
If you use the SiftAppender, you can configure a discriminator as JNDIBasedDiscriminator and use JNDI resource value to specify the source of the log file.
However it should be too time consuming.
Related info may be found in:
http://logback.qos.ch/manual/loggingSeparation.html
In my web application I have to send email to set of predefined users like finance#xyz.example, so I wish to add that to a .properties file and access it when required. Is this a correct procedure, if so then where should I place this file? I am using Netbeans IDE which is having two separate folders for source and JSP files.
It's your choice. There are basically three ways in a Java web application archive (WAR):
1. Put it in classpath
So that you can load it by ClassLoader#getResourceAsStream() with a classpath-relative path:
ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
InputStream input = classLoader.getResourceAsStream("foo.properties");
// ...
Properties properties = new Properties();
properties.load(input);
Here foo.properties is supposed to be placed in one of the roots which are covered by the default classpath of a webapp, e.g. webapp's /WEB-INF/lib and /WEB-INF/classes, server's /lib, or JDK/JRE's /lib. If the propertiesfile is webapp-specific, best is to place it in /WEB-INF/classes. If you're developing a standard WAR project in an IDE, drop it in src folder (the project's source folder). If you're using a Maven project, drop it in /main/resources folder.
You can alternatively also put it somewhere outside the default classpath and add its path to the classpath of the appserver. In for example Tomcat you can configure it as shared.loader property of Tomcat/conf/catalina.properties.
If you have placed the foo.properties it in a Java package structure like com.example, then you need to load it as below
ClassLoader classLoader = Thread.currentThread().getContextClassLoader();
InputStream input = classLoader.getResourceAsStream("com/example/foo.properties");
// ...
Note that this path of a context class loader should not start with a /. Only when you're using a "relative" class loader such as SomeClass.class.getClassLoader(), then you indeed need to start it with a /.
ClassLoader classLoader = getClass().getClassLoader();
InputStream input = classLoader.getResourceAsStream("/com/example/foo.properties");
// ...
However, the visibility of the properties file depends then on the class loader in question. It's only visible to the same class loader as the one which loaded the class. So, if the class is loaded by e.g. server common classloader instead of webapp classloader, and the properties file is inside webapp itself, then it's invisible. The context class loader is your safest bet so you can place the properties file "everywhere" in the classpath and/or you intend to be able to override a server-provided one from the webapp on.
2. Put it in webcontent
So that you can load it by ServletContext#getResourceAsStream() with a webcontent-relative path:
InputStream input = getServletContext().getResourceAsStream("/WEB-INF/foo.properties");
// ...
Note that I have demonstrated to place the file in /WEB-INF folder, otherwise it would have been public accessible by any webbrowser. Also note that the ServletContext is in any HttpServlet class just accessible by the inherited GenericServlet#getServletContext() and in Filter by FilterConfig#getServletContext(). In case you're not in a servlet class, it's usually just injectable via #Inject.
3. Put it in local disk file system
So that you can load it the usual java.io way with an absolute local disk file system path:
InputStream input = new FileInputStream("/absolute/path/to/foo.properties");
// ...
Note the importance of using an absolute path. Relative local disk file system paths are an absolute no-go in a Java EE web application. See also the first "See also" link below.
Which to choose?
Just weigh the advantages/disadvantages in your own opinion of maintainability.
If the properties files are "static" and never needs to change during runtime, then you could keep them in the WAR.
If you prefer being able to edit properties files from outside the web application without the need to rebuild and redeploy the WAR every time, then put it in the classpath outside the project (if necessary add the directory to the classpath).
If you prefer being able to edit properties files programmatically from inside the web application using Properties#store() method, put it outside the web application. As the Properties#store() requires a Writer, you can't go around using a disk file system path. That path can in turn be passed to the web application as a VM argument or system property. As a precaution, never use getRealPath(). All changes in deploy folder will get lost on a redeploy for the simple reason that the changes are not reflected back in original WAR file.
See also:
getResourceAsStream() vs FileInputStream
Adding a directory to tomcat classpath
Accessing properties file in a JSF application programmatically
Word of warning: if you put config files in your WEB-INF/classes folder, and your IDE, say Eclipse, does a clean/rebuild, it will nuke your conf files unless they were in the Java source directory. BalusC's great answer alludes to that in option 1 but I wanted to add emphasis.
I learned the hard way that if you "copy" a web project in Eclipse, it does a clean/rebuild from any source folders. In my case I had added a "linked source dir" from our POJO java library, it would compile to the WEB-INF/classes folder. Doing a clean/rebuild in that project (not the web app project) caused the same problem.
I thought about putting my confs in the POJO src folder, but these confs are all for 3rd party libs (like Quartz or URLRewrite) that are in the WEB-INF/lib folder, so that didn't make sense. I plan to test putting it in the web projects "src" folder when i get around to it, but that folder is currently empty and having conf files in it seems inelegant.
So I vote for putting conf files in WEB-INF/commonConfFolder/filename.properties, next to the classes folder, which is Balus option 2.
Ex: In web.xml file the tag
<context-param>
<param-name>chatpropertyfile</param-name>
<!-- Name of the chat properties file. It contains the name and description of rooms.-->
<param-value>chat.properties</param-value>
</context-param>
And chat.properties you can declare your properties like this
For Ex :
Jsp = Discussion about JSP can be made here.
Java = Talk about java and related technologies like J2EE.
ASP = Discuss about Active Server Pages related technologies like VBScript and JScript etc.
Web_Designing = Any discussion related to HTML, JavaScript, DHTML etc.
StartUp = Startup chat room. Chatter is added to this after he logs in.
It just needs to be in the classpath (aka make sure it ends up under /WEB-INF/classes in the .war as part of the build).
You can you with your source folder so whenever you build, those files are automatically copied to the classes directory.
Instead of using properties file, use XML file.
If the data is too small, you can even use web.xml for accessing the properties.
Please note that any of these approach will require app server restart for changes to be reflected.
Assume your code is looking for the file say app.properties. Copy this file to any dir and add this dir to classpath, by creating a setenv.sh in the bin dir of tomcat.
In your setenv.sh of tomcat( if this file is not existing, create one , tomcat will load this setenv.sh file.
#!/bin/sh
CLASSPATH="$CLASSPATH:/home/user/config_my_prod/"
You should not have your properties files in ./webapps//WEB-INF/classes/app.properties
Tomcat class loader will override the with the one from WEB-INF/classes/
A good read:
https://tomcat.apache.org/tomcat-8.0-doc/class-loader-howto.html