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[[File:icon-Java.png|64x64px||link=|alt=Java]]Java is a modern, object-oriented programming language developed by Oracle.
{{#seo:|description=Learn how to use Phidget USB devices with Java.}}
[[Category:Language]]


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


==Introduction==
==Java Libraries==
During development, we recommend downloading the appropriate installer or package for your [https://www.phidgets.com/docs/Operating_System_Support operating system]. This will place the required Phidget library files in standard locations where Java will look for them. When [[#Deploying Applications|deploying applications]], you can instead include these files manually as part of your application.


{{LanguageSupport|Java|the complete Phidget API, including events|all Phidget devices.|command line compiler as well as in integrated development environments(IDEs) such as NetBeans and Eclipse}}
====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.


==Quick Downloads==
=====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.


Just need the Java drivers, libraries, and examples?  Here they are:
[[Image:Javascript_networkserver_webusb_spec.png|center|600px|link=https://cdn.phidgets.com/docs/images/8/80/Javascript_networkserver_webusb_spec.png]]


Java API Documentation:
====Linux Considerations====
*[http://www.phidgets.com/documentation/JavaDoc.zip Java API Manual Download] or [http://www.phidgets.com/documentation/web/javadoc/index.html (HTML online version)]
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.
*[[General API]] (more help on functions common to all Phidgets)
*[[Device List | Device Specific APIs]] (more help on functions specific to your Phidget)


Java Example Code:
==Development Environment Configuration==


*[http://www.phidgets.com/downloads/examples/JavaJNI_2.1.8.20111220.zip Java Example Code]
Before choosing a development environment, make sure you have the [http://www.oracle.com/technetwork/java/index.html Java Development Kit] installed.


Libraries and Drivers:
===Visual Studio Code===
*[http://www.phidgets.com/downloads/libraries/phidget21jar_2.1.8.20111220.zip phidget21.jar]
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
*[http://www.phidgets.com/downloads/libraries/Phidget-x86_2.1.8.20111220.exe 32 bit Windows (drivers, with libraries)]
|+ '''Instructions'''
*[http://www.phidgets.com/downloads/libraries/Phidget-x64_2.1.8.20111220.exe 64 bit Windows (drivers, with libraries)]
| 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]]
*[http://www.phidgets.com/downloads/libraries/libphidget_2.1.8.20111028.tar.gz General Linux Libraries] ([[OS - Linux | Linux Library Setup Instructions]])
|-
*[http://www.phidgets.com/downloads/libraries/Phidget_2.1.8.20111103.dmg General Mac OSX Libraries] ([[OS - Mac OS X | Mac OS X Library Setup Instructions]])
| 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]]
 
|-
==Getting started with Java==
| 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]]
 
|-
If you are new to writing code for Phidgets, we recommend starting by running, then modifying existing examples. This will allow you to:
| 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].  
{{ExampleCodeReasons}}
|-
 
| 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.
Instructions are divided up by operating system. Choose:
|-
*[[#Windows(2000/XP/Vista/7)|Windows 2000 / XP / Vista / 7]]
| 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]]
*[[#Mac OS X |Mac OS X]]
|-
*[[#Linux | Linux]] (including PhidgetSBC)
| 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]]
 
|-
==Windows(2000/XP/Vista/7)==
| 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]]
 
|-
===Description of Library Files===
| colspan="2"| Now you can run your new .jar file with the following command:
Java programs on Windows depend on the following files, which the installers above put onto your system:
<syntaxhighlight>
* <b>{{Code|phidget21.dll}}</b> contains the actual Phidgets library, which is used at run-time.  If you used our installer, it's already placed in {{Code|C:\Windows\System32}}.  It can be manually installed - check our [[Manual Installation instructions]].
java -jar Example.jar
* <b>{{Code|phidget21.jar}}</b> is the Phidgets Java library for JDK <i><b>1.4.2</b></i> or higher. Your compiler has to know where this file is. By default, our installer puts this file into {{Code|C:\Program Files\Phidgets}}. So, you can either point your compiler to that location, or copy and link to it in a directory for your project workspace. For more information, please see the section for your specific compiler/environment. If you do not want to use our installer, you can download the [http://www.phidgets.com/downloads/libraries/phidget21jar_2.1.8.20111220.zip file].
</syntaxhighlight>
 
|}
Running the examples and writing your own code can be fairly compiler-specific, so we include instructions for each [[#Compilers/Environments | compilers/environments]].
 
==Mac OS X==
 
Java has excellent support on Mac OS X through the Java Compiler.
 
The first step in using Java on Mac is to install the Phidget libraries.  Compile and install them as explained on the [[Device List|getting started guide for your device]]. Then, the [[OS - Mac OS X]] page also describes the different Phidget files, their installed locations, and their roles....
 
Running the examples and writing your own code can be fairly compiler-specific, so we include instructions for each [[#Compilers/Environments | compilers/environments]].
 
==Linux==
 
Java has excellent support on Mac OS X through the Java Compiler.
 
The first step in using Java on Linux is to install the Phidget libraries.  Compile and install them as explained on the main [[OS - Linux | Linux page]]. That Linux page also describes the different Phidget files, their installed locations, and their roles.
 
Running the examples and writing your own code can be fairly compiler-specific, so we include instructions for each [[#Compilers/Environments | compilers/environments]].
 
Things to cover that are not covered below:
*Description of files
**Dependence on libphidget21.so
**Using jar in a manifest (including compiled C header)
*Use of sudo without udev rules installed
*Makefile in examples
**Use and expansion
**Other batch compiling of all examples
*Differences between gcj and openjdk packages
*Compiling lines (e.g. .:phidget21)
*Runtime linking of java file resources
*Mismatch of javac and java versions
**On command line
**On Eclipse (weird error given)
*Some information about IDEs as given below in windows, but also
**Binding netbeans to gcj (not sure if it is possible in openjdk)
**Opening simple examples (not copy and paste)
 
==Compilers/Environments==
 
You can program Phidgets with Java in command line with the {{Code|javac}} compiler as well as in IDEs such as NetBeans and Eclipse. This instructions in this section was written for a Windows environment, but the steps also holds true for Mac OS X and Linux environments.


===Javac===
===Javac===
 
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
=====Use Our Examples=====
|+ '''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]]
Download the [http://www.phidgets.com/downloads/examples/JavaJNI_2.1.8.20111220.zip example] and unpack them into a folder. Here, you can find example programs for all the devices. If you aren't sure what the software example for your device is called, check the software object listed in the [[Device List | Getting Started guide for your device]]. Please only use the simple examples. The full examples are intended for the [[#NetBeans | NetBeans IDE]].
|-
 
|[https://www.phidgets.com/downloads/phidget22/libraries/any/Phidget22Java.zip You can download phidget22.jar here].||
Ensure that the {{Code|phidget21.jar}} is in the same directory as the source code.
|-
 
|colspan="2"|To run your program, enter the following command in the command prompt or terminal:
To compile in Windows command prompt:
<syntaxhighlight>
<div class="source">
javac -classpath .;phidget22.jar example.java
<syntaxhighlight lang=bash>
javac -classpath .;phidget21.jar example.java
</syntaxhighlight>
</syntaxhighlight>
</div>
Then, enter the following command to run the program:
The command to compile in a Mac OS X and Linux terminal are slightly different. Rather than prefixing {{Code|phidget21.jar}} with a semi-colon( {{Code|;}} ), a colon( {{Code|:}} ) is used.
<syntaxhighlight>
<div class="source">
java -classpath .;phidget22.jar example  
<syntaxhighlight lang=bash>
javac -classpath .:phidget21.jar example.java
</syntaxhighlight>
</div>
This will create Java bytecode in the form of {{Code|.class}} files. On Windows, type the following to run the program:
<div class="source">
<syntaxhighlight lang=bash>
java -classpath .;phidget21.jar example
</syntaxhighlight>
</div>
 
On Mac OS X and Linux, type:
<div class="source">
<syntaxhighlight lang=bash>
java -classpath .:phidget21.jar example
</syntaxhighlight>
</syntaxhighlight>
</div>
||
 
|-
 
| colspan="2"| Once you're ready to compile your project into a .jar executable, create a '''manifest.mf''' file with the following contents:
If you wish, you can compile the project as a {{Code|.jar}} so there are fewer files to maintain. The [[http://www.oracle.com/java Java SDK]] provides the {{Code|jar}} utility which packages all the {{Code|.class}} files into a single {{Code|.jar}} file.
<syntaxhighlight>
To begin, you will have to provide a Manifest file to indicate the program entry point. With your favourite text editor, create a new file with the following content:
<div class="source">
<syntaxhighlight lang=text>
Manifest-Version: 1.0
Manifest-Version: 1.0
Class-Path: phidget21.jar
Main-Class: example
Main-Class: example
Class-Path: phidget22.jar
 
</syntaxhighlight>
</syntaxhighlight>
<br/>
Make sure there's an empty newline at the bottom of the three lines and a space after each colon.
</div> 
|-
Ensure that the file ends in a single new line or a carriage return character.  
| colspan="2"| Next, create the .jar file with this command:
Save the file as {{Code|example.mf}} and place it in the same directory as the other {{Code|.class}} files.
<syntaxhighlight>
Next, create the .{{Code|jar}} with:
jar cfm example.jar manifest.mf *.class
<div class="source">
<syntaxhighlight lang=bash>
jar -cfm example.jar example.mf *.class
</syntaxhighlight>
</syntaxhighlight>
</div>
Once the .jar is created, you can execute it with
Afterwards, you can run the {{Code|.jar}} with:
<syntaxhighlight>
<div class="source">
<syntaxhighlight lang=bash>
java -jar example.jar
java -jar example.jar
</syntaxhighlight>
</syntaxhighlight>
</div>
Once you have the Java examples running, we have a [[#Follow The Examples|teaching section]] below to help you follow them.


=====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 compiler / development environment to properly link the Phidget Java libraries. Please see the [[#Use Our Examples| previous section]] for instructions.
===Netbeans===
 
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
In your code, you will need to include the Phidget library:
|+ '''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]]
<div class="source">
|-
<syntaxhighlight lang=java>
|[https://www.phidgets.com/downloads/phidget22/libraries/any/Phidget22Java.zip You can download phidget22.jar here].||
import com.phidgets.*;
|-
import com.phidgets.event.*;
| 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]]
|-
| 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]]
|-
| 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]]
|-
| 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]]
|-
| colspan="2"| You can now run the .jar file from the command prompt with:
<syntaxhighlight>
java -jar phidgetTest.jar
</syntaxhighlight>
</syntaxhighlight>
</div>
|}
 
The project now has access to the Phidget21 function calls and you are ready to begin coding.
 
The same [[#Follow The Examples|teaching section]] which describes the examples also has further resources for programming your Phidget.
 
===NetBeans===
 
 
=====Use Our Examples=====
 
You first download the [http://www.phidgets.com/downloads/examples/JavaJNI_2.1.8.20111220.zip 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 aren't sure what the software example for your device is called, check the software object listed in the [[Device List | Getting Started guide for your device]]. The full examples were written in NetBeans, so the rest of this section will use these examples. To use the simple examples, you will have to import the source code into a new NetBeans project.
 
[[File:Java NetBeans Open Project.PNG|link=|alt=Open Project]]
 
The only thing left to do is to run the examples! Click on Run &rarr; Run Project. The project, by default tries to find the {{Code|phidget21.jar}} in {{Code|..\..\lib}}.
 
[[File:Java NetBeans Run.PNG‎|link=|alt=Run]]
 
Once you have the Java examples running, we have a [[#Follow The Examples|teaching section]] below to help you follow them.
 
=====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 compiler / development environment to properly link the Phidget Java libraries. To begin:
 
1. Create a new Java application project with a descriptive name such as PhidgetTest.
 
[[File:Java NetBeans New Project.PNG|link=|alt=New Project]]
 
2. Add a reference to the Phidgets Java library. In the projects pane, right click {{Code|Libraries}} and add the {{Code|jar}}.
 
[[File:Java NetBeans Add Jar.PNG|link=|alt=Add Jar]]
 
3. Find and select {{Code|phidget21.jar}}.
 
[[File:Java NetBeans Add Jar 2.PNG|link=|alt=Add Jar]]
 
4. Then, in your code, you will need to include the Phidget library:
 
<div class="source">
<syntaxhighlight lang=java>
import com.phidgets.*;
import com.phidgets.event.*;
</syntaxhighlight>
</div>
 
 
The project now has access to the Phidget21 function calls and you are ready to begin coding.
 
The same [[#Follow The Examples|teaching section]] which describes the examples also has further resources for programming your Phidget.


===Eclipse===
===Eclipse===
 
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
=====Use Our Examples=====
|+ '''Instructions'''
 
| 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]]
1. Download the [http://www.phidgets.com/downloads/examples/JavaJNI_2.1.8.20111220.zip examples] and unpack them into a folder. Here, you can find example programs for all the devices. If you aren't sure what the software example for your device is called, check the software object listed in the [[Device List | Getting Started guide for your device]]. Please use the simple examples. The full examples were written in NetBeans, and are not compatible with Eclipse. The rest of this guide will assume that the simple examples are used. The example source code will be copied into your Eclipse project later on. Keep note of the file name of the example as a Java class will be created with the same name.
|-
 
| 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]]
2. Generate a new Java project with a descriptive name such as PhidgetTest. Click next.
|-
 
| 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]]
[[File:Java Eclipse New Project.PNG|link=|alt=New Project]]
|-
 
| 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]]
3. On the next screen, go to the libraries panel and add an external {{Code|jar}}.
|-
 
| Your project now has access to Phidgets! ||
[[File:Java Eclipse Add Jar 1.PNG|link=|alt=Add Jar]]
|-
 
| 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]]
4. Find and select {{Code|phidget21.jar}}.
|-
 
| 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]]
[[File:Java Eclipse Add Jar 2.PNG|link=|alt=Add Jar]]
|-
 
| colspan="2"| You can now run the .jar file from the command prompt with:
5. Add a new Java class to the project.
<syntaxhighlight>
 
java -jar phidgetTest.jar
[[File:Java Eclipse New Class.PNG|link=|alt=New Class]]
 
6. Name this class with the same name as the simple example's name.  
 
[[File:Java Eclipse New Class 2.PNG|link=|alt=New Class]]
 
7. Copy and paste the example source code over to the class you created.
 
[[File:Java Eclipse Source.PNG|link=|alt=Source Code]]
 
8. The only thing left to do is to run the examples!
 
[[File:Java Eclipse Run.PNG|link=|alt=Run]]
 
 
Once you have the Java examples running, we have a [[#Follow The Examples|teaching section]] below to help you follow them.
 
=====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 compiler / development environment to properly link the Phidget Java libraries. Please see the [[#Use Our Examples 3| previous section]] for instructions.
 
In your code, you will need to include the Phidget library:
 
<div class="source">
<syntaxhighlight lang=java>
import com.phidgets.*;
import com.phidgets.event.*;
</syntaxhighlight>
</syntaxhighlight>
</div>
|}
 
The project now has access to the Phidget21 function calls and you are ready to begin coding.
 
The same [[#Follow The Examples|teaching section]] which describes the examples also has further resources for programming your Phidget.


==Follow The Examples==
=== PhidgetSBC Web Interface ===
{| style="margin:auto;" class="table-no-border mw-collapsible mw-collapsed"
|+'''Instructions'''
|<center>{{#ev:youtube|gZmWvWXICIA|rel=0}}</center>
'''Note:''' Debian Linux may not have support for the newest JDK by default, so if you're developing your code on another machine, you may have to target an older version of Java in order to run it on the PhidgetSBC.
|}


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.
==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.


Next, comes our API information. These resources outline the Phidgets Java methods:
[[Image:Language_java_codesample.png|center|600px|link=https://cdn.phidgets.com/docs/images/a/af/Language_java_codesample.png]]


{{UsingAPhidgetInCodeGeneral|both of which are available in Java|[http://www.phidgets.com/documentation/JavaDoc.zip Java API]}}
===Phidget Programming Basics===
{{PhidgetProgrammingBasicsLink}}


===Example Flow===
== Deploying Applications ==
The following files are required for your Java application:
* phidget22.jar
* phidget22.dll
* phidget22java.dll


{{ExamplePseudocode|In Java, you can name these '''event''' functions whatever you like.  You will then pass them as function pointers to the Phidget library below in the Main Code section.  This hooks them into the actual events when they occur. <br>
The 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.
In the example code, the event functions common to all Phidgets are called things like '''AttachHandler()''' and '''DetachHandler()''', etc.<br><br>
Some event functions will be specific to each device, like when a tag is read on an RFID board, or when a sensor value changes on an Interface Kit.
Other functions are given in the examples to show you more detail on using your Phidget.  For example, '''DeviceInitialize()''' will show what needs to be set up for your Phidget before using it.
|Creating a Phidget software object in Java is specific to the Phidget.  For a Phidget Spatial, for example, this would involve creating a {{Code|SpatialPhidget}} object.  The examples show how to do this and other API functions.<br><br>
The object provides device specific methods which are available from the API for your specific Phidget.|
[http://www.phidgets.com/documentation/JavaDoc.zip Java API]}}


==Common Problems and Solutions/Workarounds==
Java will look for these files in several locations, including the classpath and the working folder of the project.


Here you can put various frequent problems and our recommended solutions.
==API==
[{{SERVER}}/?view=api&lang=Python Phidget22 API]

Latest revision as of 19:01, 2 April 2026


Get Started

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

Java Libraries

During development, we recommend downloading the appropriate installer or package for your operating system. This will place the required Phidget library files in standard locations where Java will look for them. When deploying applications, you can instead include these files manually as part of your application.

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

Note: Debian Linux may not have support for the newest JDK by default, so if you're developing your code on another machine, you may have to target an older version of Java in order to run it on the PhidgetSBC.

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.

Deploying Applications

The following files are required for your Java application:

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

The 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.

API

Phidget22 API