I am building some small Java application to run on Goole AppEngine.
It is not clear to how should I configure eclipse so I'll be able to compile my project but I won't deploy stuff that already exists in on the platform.
(I've tried to read about the subject - here for example - but stil. it is not clear to me).
For example:
The Jersey and the Junit jars - I want them to be uploaded with my code to the cloud in the deployment process.
The AppEngine jars -I need them only for my design time - to be able to write code that is using the platform classes, but I don't want to upload them in the deployment process as they will be available to me by the platform.
Please help to get it right.
I think you need to read a bit from here Google Plugin for Eclipse
And also get the plugin from there, in addition , add the Jersy and the Junit (check first that the API's are on the WillItPlayInJava list) to the build path of the project
WillItPlayInJava
Related
I'm a newbie to J2ee though not a complete newbie. I'm unable to find a good resource (book or video) that could help me understand what exactly happens when we build, deploy and publish. I have a fair idea though. So my questions are -
Is there a good resource out there that can help me understand these concepts? I've read some books on struts and servlets/jsp but they don't delve into eclipse and how/what it does. The eclipse documentation has been helpful but only slightly.
When we build an application the the java files are converted into the class files and stored in the java build path. What else happens during build? Many people use the term 'library dependencies', what does this mean? Also, when people refer to dependencies do they refer to files like xml and tld?
At what stage (build or run on server) does the container check to see if the dependencies are alright? Say for instance, if the servlet class/name in the web.xml file.
Is it appropriate to say that build is basically compilation while deploying the project and running it is the same as executing it?
Familiarity with the servlet specification would help you (perhaps some older version would be quicker to read like 2.4), but general understanding of what you build and how you do it in Eclipse is what you are after.
The way I see it is that during the build Eclipse creates almost complete version of WAR (or some other archive, if you use EJBs for instance) and by publishing you deploy it to some server (this is practically the same thing although Eclipse might just configure the server to use exploded WAR that it just prepared instead of copying it to some "deploy" dir that you are supposed to do if you work without an IDE).
If you configure your project well, the build can only mean compilation, but if you have more ceremony in it, then some source generation and moving files around might happen too.
To address your second question, library dependencies can be files that reside in WEB-INF/lib for instance. Read the spec to know what should be there and what should not. Eclipse tries to copy there all defined dependencies of your project.
I have a java based appengine endpoint project in eclipse.
When I generate client library using command line tool.
https://developers.google.com/appengine/docs/java/endpoints/endpoints_tool
I'm getting only source based jar file ('project_name_version'.java-1.18.0-rc-sources.jar). It does not work fine in Android Studio when I add as a Library.
How can I get class based jar client library (google-api-services-'project_name_verison'-1.18.0-rc.jar)?
I tried searching online but no luck yet.
You could always zip up the sources file and use them in Android Studio. However , note that in the build.gradle file, you will have to reference the other dependent JAR files + versions that will be needed by the sources that you have generated in Eclipse via the Generate Cloud Endpoint Library option.
Build your app engine back end with JRE 7. You can change this from windows->preferences->java->installed JREs. You'll find an Add button at the right side of the pane. For more detail refer this Tutorial
This will solve most of your problems.
Hullo - issue is this:
I wrote a servlet in Eclipse which requires mysql-connector-java-5.1.22-bin.jar
To compile I need to add the jar via the project's "Java Build Path"
To deploy I need to add the jar to the project's "Deployment Assembly"
To run the servlet within eclipse I need to add the jar to the servlet's Run Configuration -> Classpath
It's not the end of the world re-re-repeating myself like this, but it does seem odd.
Given that Eclipse gets a lot of other stuff correct I'm guessing / hoping that maybe I'm overlooking some feature to avoid this silliness (I cannot imagine a scenario where you'd benefit from entering this in 3 different spots ... but maybe I'm being uncreative here ...).
Insights appreciated :-)
The only thing you need to do is to drop the jar in WebContent/WEB-INF/lib.
You are developing a Java Web project, so the traditional place to put the required libs (JAR files etc) is under /WEB-INF/lib. And you do it only once.
In Eclipse, when you create Dynamic Web Project the appropriate project structure is generated for you (this is a development structure). In this case you place your JAR files in ProjectName/WebContent/WEB-INF/lib folder. And this folder is *automatically included in the project's build path.
Considering the fact that it is a Java Web project (you said you use servlets) you have to deploy your web app to some Application Server, like GlassFish, JBoss, WebLogic, WebSphere etc, or more simple Web Container like Apache Tomcat. If you do this thru Eclipse, then again your web project is automatically deployed.
NB!
There may be some additional details related to using libraries.
For instance, when it comes to using database drivers (MySql, PostgreSQL, Oracle etc) Tomcat advises the following while configuring JNDI Datasource (quote):
Before you proceed, don't forget to copy the JDBC Driver's jar into
$CATALINA_HOME/lib
In your case (MySQL) see the example here: MySQL DBCP Example
Also see my answer related to Webapp configuration file organization convention.
Hope this will help you.
P.S. Here is a step-by-step example: How do I access MySQL from a web application?
From past 90 hours I am trying to know how to use Maven in my web project, generate a war file and deploy it into my JBoss 4.2 Server.
I am not getting.
I am reading all kinds of blogs, googling almost all time, trying out all kinds of way to build a dynamic web project with maven, but trying out different methods make a simple thing more complex.
Few examples tell me how to run, few tell me to change the folder structure, few tell me transfer the contents of web content but nothing is matching my requirements. In some of the examples war file is getting generated, but of some big name, and it does not contain the jars inside. Uff.
I know maven is easy and makes our lives better but learning it for the first time makes it complex.
My requirement is simple.
1) Build a Dynamic web project in eclipse indigo. (Preferably in JAVA perspective )
2) Enable Maven dependencies, in eclipse.
3) Update pom.xml to add dependencies.
4) Finish the web application i want to do by writing classes, html pages, deployment descriptors.
5) Build the war file using maven "IN ECLIPSE ONLY". (the WAR file must have user specific name and not some name like "V1- Snapshot dash dash dash")
6) Deploy my war file in jboss 4.2 server deployment location. (Preferably from eclipse )
7) Run my localhost server and my application from the browser.
And Done.
By spending time on it I am understanding how beautiful is maven, but I am not able to achieve what I want.
Please help me by giving me a detailed procedure on how to use maven to meet my requirements above.
Fist I would suggest to use the newest Eclipse (Juno) with Maven support (m2e and wtp-m2e).
The first step is to define your pom with the appropriate dependencies and the correct packaging type which is in your case war.
If you really need a different naming you should leave Maven, cause maven makes assumptions about the naming of your artifacts which usually isn't a problem. The default version patterns as 1.0.0-SNAPSHOT etc.
If you wan't to deploy the war into JBoss there exist a number of possibilites to do such things and if you like to run your application locally it sounds you wan't to do some kind of testing (integration testing) which is supported by Maven (see maven-failsafe-plugin).
Furthermore you must learn if you like to use Maven to understand that not Eclipse is anymore the leader of the project configuration. This job has been moved to Maven or in other words into the pom file. If you like to use the project in Eclipse you need to import this project into Eclipse.
Apart from the above i would suggest to go to a Maven training to lear all that stuff which is more effective than learning it yourself.
I've got a simple Dynamic Web project set up in Eclipse 3.6 Helios, but am having trouble getting it to make use of the code in another project that I've got.
I've added a reference to my other project to the build path of my web project, and I've got no problems in terms of compiling, only in terms of deploying and testing the result. The built web application doesn't have a jar in the WEB-INF/lib directory, so fair enough it can't find the code. The question is how I set this up. I've looked through the help that I can find and googled a bit but can't find anything obvious that helps out.
How do I set up my web project so that on deploying it it magically has the code from my dependent project inside it?
Thanks.
Note: Ideally I'd like a solution that doesn't involve setting up some kind of build tool. The web project deploys itself without recourse to any build tool (or at least none visible to end user), so was rather hoping that a references project could be integrated into that easily.
What goes in the deployment is determined not by the build path but by the Deployment Assembly entry in Preferences for the dynamic web project.
Use some build tool like ANT or Ivy or Maven that, on build, copies all the dependencies to WEB-INF/lib
Using a build tool is a good practice to automate build, test and deployment. You may also be interested in plug-ins like Maven Reactor.