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{{#seo:|description=Learn how to use Phidget USB devices with Java.}}
[[Category:Language]]
[[Category:Language]]
__TOC__


== Quick Downloads ==
==Get Started==
With the Phidget22 library, it's easy to create Java applications that work with Phidget devices.


=== Documentation ===
==Java Libraries==


*{{Phidget22API}} (Select Java from drop-down menu)
We recommend installing the [https://www.phidgets.com/docs/Operating_System_Support Phidget drivers] for your operating system. Installing the drivers will put required .dll files in the proper place where Java will look for them. If you want to run your application on a computer without installing our drivers, see the [[#Deploying Applications|Deploying Applications]] section.


=== Example Code ===
====macOS Considerations====
Legacy Phidgets running a HID USB stack require a driver extension (macOS 10.15 and newer) or a kernel extension (macOS 10.14 and earlier). During development, we recommend downloading the appropriate [https://www.phidgets.com/docs/OS_-_macOS#Quick_Downloads package] which will install the extension. When deploying applications, review the README in the [https://cdn.phidgets.com/downloads/phidget22/libraries/macos/Phidget22_macosdevel.zip macOS Development Files] for information about bundling the extension with your application.


*{{SampleCode|Java|Java Examples}}
=====Determining USB Stack=====
To determine which USB stack your device is running, navigate to the product page and then to the specification tab, and look for the ''USB Stack'' specification. If you are using a VINT device, navigate to the product page for the VINT Hub you are using.


=== Libraries===
[[Image:Javascript_networkserver_webusb_spec.png|center|600px|link=https://cdn.phidgets.com/docs/images/8/80/Javascript_networkserver_webusb_spec.png]]


{{AllQuickDownloads}}
====Linux Considerations====
Linux restricts access to USB devices to the root user. To run your Python application as a regular user, you'll need to [{{SERVER}}/docs/OS_-_Linux#Setting_Udev_Rules set up udev rules] on your system.


==Getting Started with Java==
==Development Environment Configuration==
Welcome to using Phidgets with Java! By using Java, you will have access to the complete Phidget22 API, including events. We also provide example code in Java for all Phidget devices.


If you are developing for Windows, keep reading. Otherwise, select your operating system to jump ahead:
Before choosing a development environment, make sure you have the [http://www.oracle.com/technetwork/java/index.html Java Development Kit] installed.  
*[[#macOS | macOS]]
*[[#Linux | Linux]]
 
== Windows ==
If you didn't come from the [[OS - Windows| Windows page]], be sure to check it out first before you continue reading!
===Javac (Command Line)===
====Use our examples====
One of the best ways to start programming with Phidgets is to use our example code as a guide. In order to run the examples, you will need to download and install the Java Development Kit from [http://www.oracle.com/technetwork/java/index.html Oracle].
 
 
Next, select an example that will work with your Phidget, and download phidget22.jar:
*{{SampleCode|C|C/C++ Examples}}
*[{{SERVER}}/downloads/phidget22/libraries/any/Phidget22Java/ phidget22.jar]


===Visual Studio Code===
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
|+ '''Instructions'''
| To start developing with Java in VSCode, open it up and install the '''Extension Pack for Java'''.||[[Image:Language_java_vscode_extension2.png|center|350px|link=https://cdn.phidgets.com/docs/images/b/b4/Language_java_vscode_extension2.png]]
|-
| Next, press '''Ctrl+Shift+P''' to open the command palette, type "java" and select '''Java: Create Java Project'''.  || [[Image:Language_java_vscode_createproj.png|center|360px|link=https://cdn.phidgets.com/docs/images/7/78/Language_java_vscode_createproj.png]]
|-
| Select "No Build Tools" and select a directory for the new project. You'll be asked for a project name, and  VSCode will create the directory structure. || [[Image:Language_java_vscode_emptyproj.png|center|350px|link=https://cdn.phidgets.com/docs/images/c/c1/Language_java_vscode_emptyproj.png]]
|-
| colspan="2"|You'll need to get a copy of '''phidget22.jar''' to put inside the "lib" folder. [https://www.phidgets.com/downloads/phidget22/libraries/any/Phidget22Java.zip You can download phidget22.jar here].
|-
| colspan="2"| You can now begin writing code in the newly created "App.java" file, or you can download a [[#Example_Code|sample program]] for your device and place it in the "src" folder.
|-
| Compile and run by pressing '''F5''' or by clicking the play button in the top right. || [[Image:Language_java_vscode_run.png|center|350px|link=https://cdn.phidgets.com/docs/images/e/ea/Language_java_vscode_run.png]]
|-
| Once you're ready to compile your project into a .jar executable, click on the '''Java Projects''' section in the explorer. || [[Image:Language_java_vscode_jar.png|center|350px|link=https://cdn.phidgets.com/docs/images/6/65/Language_java_vscode_jar.png]]
|-
| Click on the export icon, and then select your main class and click OK. || [[Image:Language_java_vscode_jar2.png|center|350px|link=https://cdn.phidgets.com/docs/images/7/74/Language_java_vscode_jar2.png]]
|-
| colspan="2"| Now you can run your new .jar file with the following command:
<syntaxhighlight>
java -jar Example.jar
</syntaxhighlight>
|}


After placing both the example file and the phidget22.jar file in the same folder, open the command prompt at that location. Next, enter the following command in the command prompt:
===Javac===
<syntaxhighlight lang="java">
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
|+ '''Instructions'''
|The easiest way to allow Java to access the Phidgets Java library is to place a copy of '''phidget22.jar''' in the same folder as your .java program.  ||[[Image:Language_java_javac_folder.png|center|350px|link=https://cdn.phidgets.com/docs/images/8/89/Language_java_javac_folder.png]]
|-
|[https://www.phidgets.com/downloads/phidget22/libraries/any/Phidget22Java.zip You can download phidget22.jar here].||
|-
|colspan="2"|To run your program, enter the following command in the command prompt or terminal:
<syntaxhighlight>
javac -classpath .;phidget22.jar example.java
javac -classpath .;phidget22.jar example.java
</syntaxhighlight>
</syntaxhighlight>
 
Then, enter the following command to run the program:
 
<syntaxhighlight>
Finally, enter the following command to run the program:
java -classpath .;phidget22.jar example  
<syntaxhighlight lang="java">
java -classpath .;phidget22.jar example
</syntaxhighlight>
 
 
[[Image:Java_javac.PNG|link= | center]]
 
 
You should now have the example up and running for your device. Play around with the device and experiment with some of the functionality. When you are ready, the next step is configuring your project and writing your own code!
 
====Configure your project====
When you are building a project from scratch, or adding Phidget functionality to an existing project, you'll need to configure your development environment to properly link the Phidget Java library.
 
 
To include the Phidget Java library, add the following line to your code:
<syntaxhighlight lang="java">
import com.phidget22.*
</syntaxhighlight>
 
You can now compile the file as shown in the previous section.
 
 
The project now has access to Phidgets. Next, view the [[#Write Code | write your own code]] section located below.
 
===NetBeans===
====Use our examples====
You first download the [[#Example_Code|examples]], unpack them into a folder, and then find the source code for your device. The source file will be named the same as the software object for your device. If you are not sure what the software object for your device is, find your Phidget in the drop-down menu in the {{Phidget22API}}. A list of objects that Phidget uses will appear in the next drop-down menu. To use the examples you will have to import the source code into a new NetBeans project.
 
Start by creating a new project
 
[[Image:java_newproject.png|link= | 500px]]
 
Next give your project a name.
 
[[Image:java_nameproject.png|link= | 500px]]
 
Now you can delete the java file that was generated for your project and drag the java file from the examples folder into its place.
 
Add the phidget22.jar to the project. Do this by expanding your project and right clicking on the libraries tab.
 
[[Image:java_addjar2.png|link=]]
 
Find and select phidget22.jar
 
[[Image:java_addjar.png|link= | 500px]]
Finally, right click the project and go to properties. Select Run from categories and change the main class to the appropriate class.
 
[[Image:java_setmainclass.png|link=]]
 
Now the only thing to do is run the project!
 
====Use our examples====
When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your development environment to properly link the Phidget Java library. To begin:
1. Create a new Java application project with a descriptive name such as PhidgetTest.
 
[[Image:java_descriptivename.png|link= | 500px]]
 
2. Add a reference to the Phidget Java library. In the projects pane, right click Libraries and add the jar.
 
[[Image:java_addjar2.png|link=]]
 
3. Find and select phidget22.jar
 
[[Image:java_addjar.png|link= | 500px]]
 
4. Then in your code, you will need to include the Phidget Java Library
 
<syntaxhighlight lang="java">
import com.phidget22.*
</syntaxhighlight>
 
The project now has access to the Phidget function calls and you are ready to begin coding.
 
===Eclipse===
====Use our examples====
1. Download the [[#Example_Code|examples]] and unpack them into a folder. Here, you can find an example program called HelloWorld which will work with any Phidget. You will also find example programs for all the devices. The source file will be named the same as the software object for your device. If you are not sure what the software object for your device is, find your Phidget in the drop-down list on the {{Phidget22API}}. A list of objects that Phidget uses will appear in the next drop-down menu.
 
2. Generate a new Java project with a descriptive name such as PhidgetTest. Click next.
 
[[Image:java_eclipse_nameproject.png |link=| 500px]]
 
3. On the next screen, go to the libraries panel and add an external jar
 
[[Image:java_eclipse_addextjar.png |link=| 500px]]
 
4. Find and select phidget22.jar
 
5. Drag the example java file into the src folder that has been created for you.
 
6. Now the only thing left to do is run the examples!
 
====Write your own code====
 
When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your development environment to properly link the Phidget Java library. Please see the previous section for instructions.
 
Follow instructions above for adding phidget22.jar to your project.
 
Next, your code will need to include the Phidget Java library:
 
<syntaxhighlight lang="java">
import com.phidget22.*
</syntaxhighlight>
</syntaxhighlight>
 
||
The project now has access to the Phidget function calls and you are ready to begin coding.
|-
 
| colspan="2"| Once you're ready to compile your project into a .jar executable, create a '''manifest.mf''' file with the following contents:
== OS X ==
<syntaxhighlight>
 
===Use our examples===
The commands to compile in a OS X and Windows terminal are slightly different. Rather than prefixing phidget22.jar with a semi-colon( ; ), a colon( : ) is used. Make sure that the phidget22.jar file is in the same directory as the code you are trying to compile.
 
<syntaxhighlight lang="java">
javac -classpath .:phidget22.jar example.java
</syntaxhighlight>
 
Then, to run the program:
 
<syntaxhighlight lang="java">
java -classpath .:phidget22.jar example
</syntaxhighlight>
 
This method can be used on any of the examples. If you are interested in using an IDE then refer to the [[#Windows|Windows]] section for information about setting up Phidgets projects in Eclipse or Netbeans.
 
===Write your own code===
 
With the method just discussed, notice that you need to link the phidget22.jar both at compile, and runtime. An alternative is to make a jar file of your program which includes the Phidget Java library. To do this first create a manifest file. A manifest is a text file used to define package related data. Make a text file called MyProgram.mf, where MyProgram is replaced by the name of your main class. Put the following lines into MyProgram.mf:
 
<syntaxhighlight lang="java">
Manifest-Version: 1.0
Manifest-Version: 1.0
Main-Class: example
Class-Path: phidget22.jar
Class-Path: phidget22.jar
Main-Class: MyProgram
 
</syntaxhighlight>
Make sure there's an empty newline at the bottom of the three lines and a space after each colon.
|-
| colspan="2"| Next, create the .jar file with this command:
<syntaxhighlight>
jar cfm example.jar manifest.mf *.class
</syntaxhighlight>
</syntaxhighlight>
 
Once the .jar is created, you can execute it with
'''Note''': The manifest file should end with a carriage return. So, there should be an extra line at the bottom of the file.
<syntaxhighlight>
After creating the manifest file, you can use the jar function to create one self-contained file with your classes and the correct classpath.
java -jar example.jar
 
<syntaxhighlight lang="java">
jar –cfm MyProgram.jar MyProgram.mf *.class
</syntaxhighlight>
</syntaxhighlight>


'''<span style="color:#FF0000">Not sure if the following is still valid</span>'''
|}
 
If porting this for an external system, such as one that your customer would be running, the Phidget library would need to be compiled and distributed along with the .jar. Although we do not directly support this, if you are interested in how to construct this, we provide both a distribution example and information on cross-compiling:
The Android Java libraries have an ARM-compiled libphidget22.so file included, as an example of distributing a compiled libphidget22.so with the jar file
The Linux page has more detail for compiling the Phidget C Libraries for an external target.


===Netbeans===
===Netbeans===
We offer in-depth tutorials on using our examples in NetBeans and Eclipse in the [[#NetBeans|Windows NetBeans]] and [[#Eclipse|Windows Eclipse]] sections.
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
 
|+ '''Instructions'''
As our full examples are written with NetBeans, but NetBeans is not part of the standard OS X application suite, we offer installation instructions here before referring to the Windows sections.
|The easiest way to allow Java to access the Phidgets Java library is to place a copy of '''phidget22.jar''' in the same folder as your .java program.  ||[[Image:Language_java_javac_folder.png|center|350px|link=https://cdn.phidgets.com/docs/images/8/89/Language_java_javac_folder.png]]
 
|-
====Installation====
|[https://www.phidgets.com/downloads/phidget22/libraries/any/Phidget22Java.zip You can download phidget22.jar here].||
To install NetBeans on a Mac, all you have to do is download the installer from [https://netbeans.org/downloads/ their website] and run it.
|-
 
| To start, open NetBeans and create a new project. Select Java Application and follow the steps as directed by Netbeans.|| [[Image:Windows_netbeans1.jpg|center|350px|link=https://cdn.phidgets.com/docs/images/c/c9/Windows_netbeans1.jpg]]
====Use our examples====
|-
Once you have NetBeans installed, running our examples will be very similar to the process described in the Windows NetBeans section.
| Next, add a reference to phidget22.jar by right-clicking on the libraries folder. || [[Image:Windows_netbeans2.jpg|center|350px|link=https://cdn.phidgets.com/docs/images/2/2b/Windows_netbeans2.jpg]]
 
|-
====Write your own code====
| Navigate to the folder where you downloaded phidget22.jar, and select it. || [[Image:Windows_netbeans3.jpg|center|350px|link=https://cdn.phidgets.com/docs/images/7/76/Windows_netbeans3.jpg]]
When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your development environment to properly link the Phidget Java library. Please see the [[#NetBeans|Windows NetBeans]] section for instructions if you are unfamiliar with NetBeans.
|-
 
| The project now has access to Phidgets. By default, Netbeans should create an executable .jar file in the '''dist''' folder of the project directory when it's built. If it didn't, go to '''Build -> Packaging''' in the project properties and make sure "Build JAR after compiling" is checked.|| [[Image:Windows_netbeans4.png|center|350px|link=https://cdn.phidgets.com/docs/images/7/78/Windows_netbeans4.png]]
In your code, you will need to include the Phidget Java library:
|-
 
| colspan="2"| You can now run the .jar file from the command prompt with:
<syntaxhighlight lang="java">
<syntaxhighlight>
import com.phidget22.*
java -jar phidgetTest.jar
</syntaxhighlight>
</syntaxhighlight>
|}


The project now has access to the Phidget function calls and you are ready to begin coding.
===Eclipse===
 
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
== Linux '''<span style="color:#FF0000">Unsure about information in this section</span>'''==
|+ '''Instructions'''
Java has excellent support on Linux - there is an established implementation of the Java compiler and interpreter, and several Integrated Development Environments (IDEs) including NetBeans and Eclipse.
| To start, open Eclipse and create a new Java project. Name the project and uncheck the '''create module-info.java file''' box.|| [[Image:java_eclipse_newproj.png|center|350px|link=https://cdn.phidgets.com/docs/images/9/97/Java_eclipse_newproj.png]]
 
|-
The first step in using Java on Linux is to install the base Phidget libraries. Compile and install them as explained on the main [[OS - Linux|Linux]] page. That Linux page also describes the different basic Phidget library files, their installed locations, and their roles.
| On the Libraries tab, click Add External JARs and add [https://www.phidgets.com/downloads/phidget22/libraries/any/Phidget22Java.zip phidget22.jar]. to your project as an external jar. Be sure it's being added to the '''Classpath''' and not the module path. || [[Image:java_eclipse_library.png|center|350px|link=https://cdn.phidgets.com/docs/images/1/1b/Java_eclipse_library.png]]
 
|-
You will also need the Phidget Java Libraries (phidget22.jar), from the [[#Quick_Downloads| quick downloads]] section.
| Create a new Class in your project. || [[Image:java_eclipse_newclass.png|center|350px|link=https://cdn.phidgets.com/docs/images/0/02/Java_eclipse_newclass.png]]
 
|-
Once downloaded, the phidget22.jar library file does not get 'installed' (i.e. do not run java -jar phidget22.jar). Rather, the library file gets put into the path of whatever program you write, and you will link it via both the java compiler and the java interpreter. We walk you through this below.
| Name the class, and be sure to check the '''public static void main''' box. Eclipse may require that you add a package name. || [[Image:java_eclipse_newclass2.png|center|350px|link=https://cdn.phidgets.com/docs/images/c/ca/Java_eclipse_newclass2.png]]
 
|-
===Description of Library Files===
| Your project now has access to Phidgets! ||
The Phidget Java libraries depend on the C libraries being installed as explained on the main Linux page. If you browse around within the phidget22.jar archive, you will find Java class files (too many to reasonably list here) that have names related to the devices they provide an API for.
|-
 
| Once you're ready to compile your project into a .jar executable, right click on the project in the package explorer and choose '''Export'''. Select '''Runnable JAR file'''. || [[Image:java_eclipse_export.png|center|350px|link=https://cdn.phidgets.com/docs/images/8/8c/Java_eclipse_export.png]]
These Java class files use the functions available in the dynamic Phidget22 C-language library on Linux. Dynamic libraries end with .so, and so the C library that the Phidget Java class files use is /usr/lib/libphidget22.so.
|-
 
| Choose the main class and a destination for the .jar file and click finish. || [[Image:java_eclipse_export2.png|center|350px|link=https://cdn.phidgets.com/docs/images/8/8d/Java_eclipse_export2.png]]
===Javac (Command Line)===
|-
====Use our examples====
| colspan="2"| You can now run the .jar file from the command prompt with:
Linux gets somewhat complicated in that two Java compilers exist: openjdk and gcj. Furthermore, a given IDE can usually use either compiler. That being said, we only offer support here for openJDK and IDEs running openJDK.
<syntaxhighlight>
 
java -jar phidgetTest.jar
To find out which type of compiler your computer has, use the -version option on the command line. You can use the same option for your runtime environment (interpreter):
 
<syntaxhighlight lang="java">
$> java -version
java version "1.6.0_23"
OpenJDK Runtime Environment (IcedTea6 1.11pre) (6b23~pre11-0ubuntu1.11.10.1)
OpenJDK 64-Bit Server VM (build 20.0-b11, mixed mode)
$> javac -version
javac 1.6.0_23
</syntaxhighlight>
</syntaxhighlight>
|}


The good news is that you can have both openjdk and gcj on your machine, co-habitating happily. There can be only one linked java and javac in /usr/bin/ however, and so this will correspond to whichever java compiler and interpreter you installed last.
=== PhidgetSBC Web Interface ===
 
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
If you do not have openjdk installed already (this is the default Java installation for most Linux machines, so you will probably know), and you choose to install it for Phidget purposes, it is important is that the java version be greater than the javac version. Otherwise, your runtime environment will consider the stuff your compiler produces to be newfangled nonsense. So when installing Java from a repository, you should install both the jdk and the jre. These are, unfortunately, usually separate packages in a repository (e.g. openjdk-7-jre and openjdk-7-jdk).
|+'''Instructions'''
 
|<center>{{#ev:youtube|gZmWvWXICIA|rel=0}}</center>  
The simple examples in Java are meant to be compiled and run on the command line. The example package includes a Makefile so you can either make all of the examples at once, with:
|}
 
<syntaxhighlight lang="java">
make all
</syntaxhighlight>
 
...Or you can make them individually. You can either use:
 
*The HelloWorld example, which will work with any Phidget, or
*The example with the name that corresponds to the family (software object) of your Phidget hardware.
 
The source file will be named the same as the software object for your device. If you are not sure what the software object for your device is, find your Phidget on our webpage, and then check the {{Phidget22API}} documentation for it. Once you've identified the right example - say, HelloWorld.java - compile it on the command line with:
 
<syntaxhighlight lang="java">
javac -classpath .:phidget22.jar HelloWorld.java
</syntaxhighlight>
 
To run the example on a Linux machine without your udev USB rules set, you will need to run the Java example as root:
 
<syntaxhighlight lang="java">
javac -classpath .:phidget22.jar HelloWorld.java
</syntaxhighlight>
 
====Write your own code====
 
You'll note that the Phidget Java library file phidget22.jar needs to be explicitly linked at both points in the compile and run process. Alternatively, you can make a jar file which includes the Phidget Java library. This process takes two steps, the first of which is creating a text file called MyProgram.mf, where MyProgram is replaced by the name of your main class in both the filename and the text below:
 
<syntaxhighlight lang="java">
Manifest-Version: 1.0
Class-Path: phidget22.jar
Main-Class: MyProgram
</syntaxhighlight>
 
'''Note:''' The manifest file should end with a carriage return. So, there should be an extra line at the bottom of the file.
After creating the manifest file, you can use the jar function to create one self-contained file with your classes and the correct classpath.
 
<syntaxhighlight lang="java">
jar –cfm MyProgram.jar MyProgram.mf *.class
</syntaxhighlight>
 
If porting this for an external system, such as one that your customer would be running, the Phidget library would need to be compiled and distributed along with the .jar. Although we do not directly support this, if you are interested in how to construct this, we provide both a distribution example and information on cross-compiling:
*The Android Java libraries have an ARM-compiled libphidget22.so file included, as an example of distributing a compiled libphidget22.so with the jar file
*The Linux page has more detail for compiling the Phidget C Libraries for an external target.
 
===NetBeans===
We offer in-depth tutorials on using our examples in NetBeans and Eclipse in the [[#NetBeans|Windows NetBeans]] and [[#Eclipse|Windows Eclipse]] sections.
 
====Installation====
Although Eclipse is standard in the Debian/Ubuntu package repository, NetBeans is no longer standard. What is more, Netbeans does not install by default into a folder within your path.
 
To install NetBeans:
 
1. Download the install script from website: '''<span style="color:#FF0000">http://netbeans.org/downloads/</span>'''
 
2. Change the permissions of the downloaded file to be executable. Usually, this is something like:
 
chmod +x netbeans-7.1-ml-javase-linux.sh
3. Run the downloaded file as a script. (This will result in a GUI interaction that walks you through installation.)
 
4. To find the location where the NetBeans installation occurred, run:
updatedb
locate netbeans
 
5. Usually, the location of the binary is /usr/local/netbeans-7.1/bin/netbeans, where 7.1 is the installed version.
 
====Use our examples====
Once you have NetBeans installed, running our examples will be very similar to the process described in the Windows NetBeans section
 
====Write your own code====
When you are building a project from scratch, or adding Phidget function calls to an existing project, you'll need to configure your development environment to properly link the Phidget Java library. Please see the Windows NetBeans section for instructions if you are unfamiliar with NetBeans.
In your code, you will need to include the Phidget Java library:
 
<syntaxhighlight lang="java">
import com.phidget22.*
</syntaxhighlight>
 
The project now has access to the Phidget function calls and you are ready to begin coding.
 
== Edit the Examples ==
 
By following the instructions for your operating system and compiler above, you probably now have a working example and want to understand it better so you can change it to do what you want. This teaching section has resources for you to learn from the examples and write your own.
Your main reference for writing Java code will be the {{Phidget22API}}.


=== Code Snippets ===
==Example Code==
Navigate to our [https://www.phidgets.com/?view=code_samples&lang=Java Code Sample Generator] to view and download code samples that are tailored to your specific device.


When programming in Java, you're in luck. All of our code snippet examples on our [[Phidget Programming Basics]] page are in both C++ and Java. Therefore, we do not include any here, because that page is much more in-depth, and you won't have to have two pages open at once. So head over there, and start writing code!
[[Image:Language_java_codesample.png|center|600px|link=https://cdn.phidgets.com/docs/images/a/af/Language_java_codesample.png]]


== Further Reading ==
===Phidget Programming Basics===
{{PhidgetProgrammingBasicsLink}}


[[Phidget Programming Basics]] - Here you can find the basic concepts to help you get started with making your own programs that use Phidgets.
==API==
[{{SERVER}}/?view=api&lang=Python Phidget22 API]


[[Data Interval/Change Trigger]] - Learn about these two properties that control how much data comes in from your sensors.
== Deploying Applications ==


[[Using Multiple Phidgets]] - It can be difficult to figure out how to use more than one Phidget in your program. This page will guide you through the steps.
If you're planning to deploy your application, it should be noted that you don't strictly need the Phidget Drivers installed.  


[[Polling vs. Events]] - Your program can gather data in either a polling-driven or event-driven manner. Learn the difference to determine which is best for your application.
At a minimum, these three files are required:
* phidget22.jar
* phidget22.dll
* phidget22java.dll


[[Logging, Exceptions, and Errors]] - Learn about all the tools you can use to debug your program.
All three files can be found in the [https://cdn.phidgets.com/downloads/phidget22/libraries/windows/Phidget22-windevel.zip Development Files]. The .jar file is in lib/java, and the .dll files are in lib/c/x64.  


[[Phidget Network Server]] - Phidgets can be controlled and communicated with over your network- either wirelessly or over ethernet.
Java will look for these files in several locations, including the classpath and the working folder of the project.

Latest revision as of 20:05, 1 April 2026


Get Started

With the Phidget22 library, it's easy to create Java applications that work with Phidget devices.

Java Libraries

We recommend installing the Phidget drivers for your operating system. Installing the drivers will put required .dll files in the proper place where Java will look for them. If you want to run your application on a computer without installing our drivers, see the Deploying Applications section.

macOS Considerations

Legacy Phidgets running a HID USB stack require a driver extension (macOS 10.15 and newer) or a kernel extension (macOS 10.14 and earlier). During development, we recommend downloading the appropriate package which will install the extension. When deploying applications, review the README in the macOS Development Files for information about bundling the extension with your application.

Determining USB Stack

To determine which USB stack your device is running, navigate to the product page and then to the specification tab, and look for the USB Stack specification. If you are using a VINT device, navigate to the product page for the VINT Hub you are using.

Javascript networkserver webusb spec.png

Linux Considerations

Linux restricts access to USB devices to the root user. To run your Python application as a regular user, you'll need to set up udev rules on your system.

Development Environment Configuration

Before choosing a development environment, make sure you have the Java Development Kit installed.

Visual Studio Code

Instructions
To start developing with Java in VSCode, open it up and install the Extension Pack for Java.
Language java vscode extension2.png
Next, press Ctrl+Shift+P to open the command palette, type "java" and select Java: Create Java Project.
Language java vscode createproj.png
Select "No Build Tools" and select a directory for the new project. You'll be asked for a project name, and VSCode will create the directory structure.
Language java vscode emptyproj.png
You'll need to get a copy of phidget22.jar to put inside the "lib" folder. You can download phidget22.jar here.
You can now begin writing code in the newly created "App.java" file, or you can download a sample program for your device and place it in the "src" folder.
Compile and run by pressing F5 or by clicking the play button in the top right.
Language java vscode run.png
Once you're ready to compile your project into a .jar executable, click on the Java Projects section in the explorer.
Language java vscode jar.png
Click on the export icon, and then select your main class and click OK.
Language java vscode jar2.png
Now you can run your new .jar file with the following command: 
java -jar Example.jar

Javac

Instructions
The easiest way to allow Java to access the Phidgets Java library is to place a copy of phidget22.jar in the same folder as your .java program.
Language java javac folder.png
You can download phidget22.jar here.
To run your program, enter the following command in the command prompt or terminal: 
javac -classpath .;phidget22.jar example.java

Then, enter the following command to run the program: 

java -classpath .;phidget22.jar example
Once you're ready to compile your project into a .jar executable, create a manifest.mf file with the following contents: 
Manifest-Version: 1.0
Main-Class: example
Class-Path: phidget22.jar
 

Make sure there's an empty newline at the bottom of the three lines and a space after each colon.

Next, create the .jar file with this command: 
jar cfm example.jar manifest.mf *.class

Once the .jar is created, you can execute it with 

java -jar example.jar

Netbeans

Instructions
The easiest way to allow Java to access the Phidgets Java library is to place a copy of phidget22.jar in the same folder as your .java program.
Language java javac folder.png
You can download phidget22.jar here.
To start, open NetBeans and create a new project. Select Java Application and follow the steps as directed by Netbeans.
Windows netbeans1.jpg
Next, add a reference to phidget22.jar by right-clicking on the libraries folder.
Windows netbeans2.jpg
Navigate to the folder where you downloaded phidget22.jar, and select it.
Windows netbeans3.jpg
The project now has access to Phidgets. By default, Netbeans should create an executable .jar file in the dist folder of the project directory when it's built. If it didn't, go to Build -> Packaging in the project properties and make sure "Build JAR after compiling" is checked.
Windows netbeans4.png
You can now run the .jar file from the command prompt with: 
java -jar phidgetTest.jar

Eclipse

Instructions
To start, open Eclipse and create a new Java project. Name the project and uncheck the create module-info.java file box.
Java eclipse newproj.png
On the Libraries tab, click Add External JARs and add phidget22.jar. to your project as an external jar. Be sure it's being added to the Classpath and not the module path.
Java eclipse library.png
Create a new Class in your project.
Java eclipse newclass.png
Name the class, and be sure to check the public static void main box. Eclipse may require that you add a package name.
Java eclipse newclass2.png
Your project now has access to Phidgets!
Once you're ready to compile your project into a .jar executable, right click on the project in the package explorer and choose Export. Select Runnable JAR file.
Java eclipse export.png
Choose the main class and a destination for the .jar file and click finish.
Java eclipse export2.png
You can now run the .jar file from the command prompt with: 
java -jar phidgetTest.jar

PhidgetSBC Web Interface

Instructions

Example Code

Navigate to our Code Sample Generator to view and download code samples that are tailored to your specific device.

Language java codesample.png

Phidget Programming Basics

To learn more about the structure of the example code, visit our Phidget Programming Basics guide.

API

Phidget22 API

Deploying Applications

If you're planning to deploy your application, it should be noted that you don't strictly need the Phidget Drivers installed.

At a minimum, these three files are required:

  • phidget22.jar
  • phidget22.dll
  • phidget22java.dll

All three files can be found in the Development Files. The .jar file is in lib/java, and the .dll files are in lib/c/x64.

Java will look for these files in several locations, including the classpath and the working folder of the project.

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