I have 2 Java projects in my Eclipse workspace, as follows:
One is a library of code that automatically creates a .jar file whenever it builds.
The other is an application that uses classes in that library, and references the .jar file created by the library project (by right-clicking the app -> Build Path -> Configure Build Path -> Libraries -> Add JARs...)
However, whenever I modify classes in my library project, although I can see that the library .jar gets updated, the app project doesn't pick up the changes unless I remove the library .jar from the app's referenced libraries and re-add it
Am I fundamentally doing something wrong? Is there perhaps a better way to connect an app to a shared library of code? How can I make sure my app will always refer to the latest library code?
Instead of adding it as a JAR dependency you could add it as a project dependency. Right click your project and go to properties. Click on 'Java Build Path' and select the 'Projects' tab. Click 'Add..." and add your library project.
With the latest Eclipse (I'm sure it also worked the same with the ones before), doing a refresh and Clean on your library project then on your application will update the libraries referenced.
Related
Eclipse automatically adds everything in WEB-INF/lib (specified in deployment assembly) to the project's build path. Is there a way to override this behavior? I need for another project jar to be deployed and available at run time but not have a forced compile-time dependency on it. Thanks!
Go to the properties window of the project. Then go to java build path tab and remove the relevant other project from libraries there. Then go to projects in the same tab and select the required project by using the add option and add it. Then restart Eclipse.
How do I import a jar in Eclipse?
You can add a jar in Eclipse by right-clicking on the Project → Build Path → Configure Build Path. Under Libraries tab, click Add Jars or Add External JARs and give the Jar. A quick demo here.
The above solution is obviously a "Quick" one. However, if you are working on a project where you need to commit files to the source control repository, I would recommend adding Jar files to a dedicated library folder within your source control repository and referencing few or all of them as mentioned above.
Adding external Jar is not smart in case you want to change the project location in filesystem.
The best way is to add the jar to build path so your project will compile if exported:
Create a folder called lib in your project folder.
copy to this folder all the jar files you need.
Refresh your project in eclipse.
Select all the jar files, then right click on one of them and select Build Path -> Add to Build Path
Two choices:
1/ From the project:
2/ If you have already other jar imported, from the directory "References Libraries":
Both will lead you to this screen where you can mange your libraries:
Here are the steps:
click File > Import. The Import window opens.
Under Select an import source, click J2EE > App Client JAR file.
Click Next.
In the Application Client file field, enter the location and name of the application client JAR file that you want to import. You can click the Browse button to select the JAR file from the file system.
In the Application Client project field, type a new project name or select an application client project from the drop-down list. If you type a new name in this field, the application client project will be created based on the version of the application client JAR file, and it will use the default location.
In the Target runtime drop-down list, select the application server that you want to target for your development. This selection affects the run time settings by modifying the class path entries for the project.
If you want to add the new module to an enterprise application project, select the Add project to an EAR check box and then select an existing enterprise application project from the list or create a new one by clicking New.
Note: If you type a new enterprise application project name, the enterprise application project will be created in the default location with the lowest compatible J2EE version based on the version of the project being created. If you want to specify a different version or a different location for the enterprise application, you must use the New Enterprise Application Project wizard.
Click Finish to import the application client JAR file.
Just a comment on importing jars into Eclipse (plug-in development) projects:
In case you are developing Eclipse plug-ins, it makes sense to use Eclipse's native bundling mechanism instead of just importing the jar into a plug-in project. Eclipse (or better its underlying OSGi runtime, Equinox) uses so-called bundles which contain some more information than plain jars (e.g., version infos, dependencies to other bundles, exported packages; see the MANIFEST.MF file). Because of this information, OSGi bundles can be dynamically loaded/unloaded and there is automatic dependency resolution available in an OSGi/Eclipse runtime. Hence, using OSGi bundles instead of plain jars (contained inside another OSGi bundle) has some advantages.
(BTW: Eclipse plug-ins are the same thing as OSGi bundles.)
There is a good chance that somebody already bundled a certain (3rd party) library as an OSGi bundle. You might want to take a look at the following bundle repositories:
http://www.springsource.com/repository/app/
http://download.eclipse.org/tools/orbit/downloads/
http://www.osgi.org/Repository/HomePage
Eclipse -> Preferences -> Java -> Build Path -> User Libraries -> New(Name it) -> Add external Jars
(I recommend dragging your new libraries into the eclipse folder before any of these steps to keep everything together, that way if you reinstall Eclipse or your OS you won't have to rwlink anything except the JDK) Now select the jar files you want. Click OK.
Right click on your project and choose Build Path -> Add Library
FYI just code and then right click and Source->Organize Imports
Jar File in the system path is:
C:\oraclexe\app\oracle\product\10.2.0\server\jdbc\lib\ojdbc14.jar
ojdbc14.jar(it's jar file)
To import jar file in your Eclipse IDE, follow the steps given below.
Right-click on your project
Select Build Path
Click on Configure Build Path
Click on Libraries, select Modulepath and select Add External JARs
Select the jar file from the required folder
Click and Apply and Ok
first of all you will go to your project what you are created
and next right click in your mouse and select properties in the bottom
and select build in path in the left corner and add external jar file add click apply .that's it
In eclipse I included a compressed jar file i.e. zip file. Eclipse allowed me to add this zip file as an external jar but when I tried to access the classes in the jar they weren't showing up.
After a lot of trial and error I found that using a zip format doesn't work. When I added a jar file then it worked for me.
Right Click on the Project.
Click on Build Path.
Click On Configure Build Path.
Under Libraries, Click on Add Jar or Add External Jar.
If you are having a trouble on udemy course of chad on springboot for the importing the jar. Then follow these steps.
Right click on the project.
You will see a option of Build Path, click on it.
You will have a option of Configure Build path, click on it.
Go to libraries.
Then go to the place where you have a jar files make them into a new folder and upload on a new place.
Then click on Add External Jars, you will surely be able to upload it which will help on classpathxmlapplicationcontext as well.
Thank you.
I've created an Android project in Eclipse and I would like to add the Volley library to it. Searching on the web, I've tried these approaches:
Copy the .jar into the libs folder and right-click and add it to build-path.
Open the library as an android project, mark it as library and add it as a reference in my android app.
Nothing works. I still cannot access the classes provided by the library by importing the classes like follow: com.android.volley
Someone has a solution for this ?
The Solution:
Try this:
Add volley.jar to the libs folder. Don't add it to the build
path.
In Eclipse go to Project and make sure Build Automatically is selected.
Now in Project, click on Clean:
Project -> select Clean -> select the project.
As Volley doesn't have any resources like styles, layouts etc., its not necessary to reference it as a library project. The above should work, provided all steps are followed.
If this doesn't work ...
Make sure the library has not been added to the build path. If it is, then remove it. Now, try:
Closing and re-opening the project.
Restarting the IDE (last resort).
The build process for Volley has changed to Gradle. If you just want to use the library without building it, you can get the Jar from Maven or scroll down to the instructions to building it yourself lower in this answer.
Maven
An easier way to obtain the Jar file is to download it directly from Maven Central. You can find the latest version with this search:
http://search.maven.org/#search%7Cga%7C1%7Cg%3A%22com.mcxiaoke.volley%22
At the time of writing the 1.0.19 version can be found here:
http://search.maven.org/remotecontent?filepath=com/mcxiaoke/volley/library/1.0.19/library-1.0.19.jar
Gradle
The new way to do it is to build the project using Gradle.
You can do this by running:
git clone https://android.googlesource.com/platform/frameworks/volley
gradle build
This will create a file in
build\intermediates\bundles\release
Then add this file into your libs folder and add it to your project.
I'd like to know how I can add Java libraries to an Eclipse project on a development machine so that they can be added to an Eclipse project without causing errors when someone who has the library in a different location. For example, one developer might add an external JAR in C:\Java, but another might have the same JAR somewhere else. (Where's C:\Java on Mac OS?) I thought I might set the CLASSPATH environment variable, but I can't figure how to add an external JAR from the CLASSPATH environment variable. I'd like to do this so that it works with any workspace. Is this possible?
This is specifically for use with Anypoint Studio, but I think the same problem would exist with any Eclipse-based IDE.
In general, it's recommended to either embed JARs directly into the project, usually in a /lib folder of the project, as described here; or to use a tool like Gradle or Maven to manage dependencies, both of which have nice plugins to support their use in Eclipse.
Another alternative would be to use a Classpath Variable to refer to the JAR(s), which abstracts the physical location so that it can be set on a per-workspace basis.
I think the best way to add library to eclipse project is creating a directory - lib in your project directory. Then add the whole lib to you eclipse class path. You can follow these step to add a lib to class path -
Right click on project and select properties
Select Java Build Path
click Add Library and create User Library
Now add External Jars to this library create at step 3.
By this a .classpath file is crated in you project directory and the CLASSPATH problem will be resolved
I guess the best way to do that would be using Maven, or a similar build system that can construct your Classpath base on dependencies.
You can add the dependencies to your pom and having the jars in your local maven repository in the machine.
http://maven.apache.org/guides/introduction/introduction-to-dependency-mechanism.html
Because in any other approach you will need to maintain everything manually, and when having different OS the path will change.
Eclipse is just the IDE that will help to write code and assemble the project (JAR, WAR, ... ). You can add your external jars from wherever you want, and when you want to export your project (with eclipse) you may choose to package the required libraries into the jar.
However, I recommend always to use maven (or something like ) to avoid this kind of problems.
Part1:(import .jar file as library in Eclipse)
You make a new project to Eclipse(name:Project1)
When you open it you see JRE System Library[java version something]
1.right click on JRE System Library
2.Go->Build Path->Configure Build Path
3.You can see (Up right Corner the button[add jars or add external jars]
*Here i advise you to choose the first(add jars) but..
*First copy(or move) the (name).jar inside the project((example):Project 1)
*Now you can add it with the button(add jars).
*In this way when you finish your project the (name).jar will be
imported inside the project(If you export it as a .jar from Eclipse)
..Now you can call any method of (name).jar just(import it into the class
you want to use and call it)
It's been tedious. This is the API I am trying to use. Its resources were set up in a pom.xml which I built using Maven. On built up, it gave me the project socrata-publisher that has
src/main/java the source folder with packages com.socrata.api com.socrata.data, com.socrata.util where each contains only .java
files
JRE System Library and Maven Dependency hierarchies where each contains a number of jar files
Problem is com.socrata.api and the 2 other contains classes which I want to deploy in a project outside socrata-publisher. I tried using import com.socrata.api but it didn't work. Moreover, since its a Java project and not android it doesn't have the is Library option in preferences which could rather give me the solution. Both socrata-publisher and tutorial (where i want to use the resources and which is the android application) lie in the same directory eclipseApps in My Documents.
Here's a little visual queue. Help will be greatly appreciated.
You will need to first of all get the output of the socrata project and all its dependencies.
In command line, going to the project folder of the socrata project, where the pom.xml file is, run MVN INSTALL. You shall see a jar file called socrata-api.jar in $HOME/.m2/repository. If you are using windows and installed MAVEN by default, $HOME should be your user profile folder. Once you see the jar file, add it to your tutorial build path.
I think what you actually want to do is just set up the "socrata-publisher" as a project dependency for your "tutorial" project. That will allow you to reference the built Socrata libraries from the code in your project.
Right click on the project and select "Properties". From within that dialog select "Java Build Path" on the left, then the "Projects" section, and click the "Add" button to add the "socrata-publisher" project.
I think that'll work better than creating a separate jar file that you then include, and then you can also keep the socrata-publisher code up to date using Git.