B4J Question I need help to call external jar 🙋‍♂️

[jinyistudio]

Hi
This libray has a .jar file. But I don’t know how to write java. I would like to ask you to help me write a sample program on how to call it. Let me test and modify it myself. Thank you

BlinkStick Pro

BlinkStick Pro - easiest way to control LED strips

www.blinkstick.com

BlinkStick - API Implementation

BlinkStick source code for various programming languages

www.blinkstick.com

Javadocs: BlinkStick

Blinkstick Processing by arvydas

InitializeNewInstance always give me error => java.lang.ClassNotFoundException: java$blinkstick$class$BlinkStick Can you tell me where is the error?

class manual => http://arvydas.github.io/blinkstick-processing/reference/index.html

Sub Class_Globals
    Dim blinkst As JavaObject
    Private ptObject    As Object
    Private ptEvent     As Object   
    Private ptId         As String=""
End Sub

'Initializes the object. You can add parameters to this method if needed.
Public Sub Initialize(owner As Object,event As Object,Id As String)
    ptObject= owner
    ptEvent    = event
    ptId    = Id
    blinkst.InitializeNewInstance("java.blinkstick.class.BlinkStick",Null)
End Sub

 

[Erel]

It should be:

  blinkst.InitializeNewInstance("blinkstick.BlinkStick",Null)

 

[jinyistudio]

It should be:

  blinkst.InitializeNewInstance("blinkstick.BlinkStick",Null)

Your code OK. I can try other functions Go Go, thank you

 

[Erel]

 

[jinyistudio]

It should be:

  blinkst.InitializeNewInstance("blinkstick.BlinkStick",Null)

following method in the BlinkStick, How can i dim a BlinkStick variable to receive from findFirst()
public static BlinkStick findFirst()

 

[Erel]

Dim jo As JavaObject
Dim blink As JavaObject = jo.InitializeStatic("blinkstick.BlinkStick").RunMethod("findFirst", Null)

 

[jinyistudio]

Dim jo As JavaObject
Dim blink As JavaObject = jo.InitializeStatic("blinkstick.BlinkStick").RunMethod("findFirst", Null)

Hi Erel
Function findAll is return array. I try Dim jo() As JavaObject = findAll but I get following exception

(Exception) java.lang.Exception: java.lang.ClassCastException: class [Lblinkstick.BlinkStick; cannot be cast to class [Lanywheresoftware.b4j.object.JavaObject; ([Lblinkstick.BlinkStick; and [Lanywheresoftware.b4j.object.JavaObject; are in unnamed module of loader 'app')

Try
Sub findAll As JavaObject()
    Dim jo As JavaObject
    Return jo.InitializeStatic("blinkstick.BlinkStick").RunMethod("findAll", Null)
End Sub

• findAll
  public static BlinkStick[] findAll()
  Find all BlinkSticks connected to the computer
  Returns:an array of BlinkStick objects​

​

 

[agraham]

You don't want an array of JavaObjects, you want to return a single JavaObject instance that contains the array.

Sub findAll As JavaObject
    Dim jo As JavaObject
    Return jo.InitializeStatic("blinkstick.BlinkStick").RunMethod("findAll", Null)
End Sub

 

[Erel]

You need to use an array of objects:

Sub findAll As Object()
    Dim jo As JavaObject
    Return jo.InitializeStatic("blinkstick.BlinkStick").RunMethod("findAll", Null)
End Sub

Dim blinks() As Object = findAll
If blinks.Length > 0 Then
 Dim blink As JavaObject = blinks(0)

 

[jinyistudio]

You don't want an array of JavaObjects, you want to return a single JavaObject instance that contains the array.

Sub findAll As JavaObject
    Dim jo As JavaObject
    Return jo.InitializeStatic("blinkstick.BlinkStick").RunMethod("findAll", Null)
End Sub

Thank you @agraham your code is

 

[jinyistudio]

following is my main codes

'Non-UI application (console / server application)
#Region Project Attributes
    #CommandLineArgs:
    #MergeLibraries: True
    #AdditionalJar: BlinkStick.jar
    #AdditionalJar: hidapi-1.1.jar
#end region

Sub Process_Globals
    Dim bs1 As jyBlinkstick
    Dim timer1 As Timer
    Dim flow As Boolean
End Sub

Sub AppStart (Args() As String)
    bs1.Initialize(Me,"bs1","1")     
    If bs1.findfirst=1 Then
        Log($"serial        : ${bs1.BlinkStick(0).Serial}"$)
        Log($"Version        : ${bs1.BlinkStick(0).version}"$)
        Log($"Product        : ${bs1.BlinkStick(0).Product}"$)
        Log($"Manufacturer    : ${bs1.BlinkStick(0).Manufacturer}"$)
        Log($"info1            : ${bs1.BlinkStick(0).InfoBlock1}"$)
        Log($"info2            : ${bs1.BlinkStick(0).InfoBlock2}"$)
        Log($"Mode2            : ${bs1.BlinkStick(0).Mode}"$)
      
        timer1.Initialize("timer1",1000)
        timer1.Enabled=True
        flow=False
    End If
  
    StartMessageLoop
  
  
End Sub


Sub timer1_tick
    If flow Then
        bs1.BlinkStick(0).setIndexedColor16(0,0,0,0,0)
    Else
        bs1.BlinkStick(0).setIndexedColor16(0,0,Rnd(1,255),Rnd(1,255),Rnd(1,255))
    End If
    flow = Not(flow)
End Sub

I debug with b4j-bridge. I get follow messages when i running jo.InitializeStatic("blinkstick.BlinkStick").RunMethod("findFirst", Null) in the raspberry pi ?

Waiting for debugger to connect...
Program started.
OpenJDK Server VM warning: You have loaded library /tmp/libhidapi-jni-6417314661532003353684.so which might have disabled stack guard. The VM will try to fix the stack guard now.
It's highly recommended that you fix the library with 'execstack -c <libfile>', or link it with '-z noexecstack'.
Error occurred on line: 37 (jyBlinkstick)
java.lang.ClassCastException: class java.lang.UnsatisfiedLinkError cannot be cast to class java.lang.Exception (java.lang.UnsatisfiedLinkError and java.lang.Exception are in module java.base of loader 'bootstrap')
at anywheresoftware.b4a.BA.setLastException(BA.java:377)
at b4j.example.jyblinkstick._findfirst(jyblinkstick.java:111)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at anywheresoftware.b4a.shell.Shell.runMethod(Shell.java:632)
at anywheresoftware.b4a.shell.Shell.raiseEventImpl(Shell.java:234)
at anywheresoftware.b4a.shell.Shell.raiseEvent(Shell.java:167)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessor
Impl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:566)
at anywheresoftware.b4a.BA.raiseEvent2(BA.java:108)
at anywheresoftware.b4a.shell.ShellBA.raiseEvent2(ShellBA.java:98)
at anywheresoftware.b4a.BA.raiseEvent(BA.java:95)
at b4j.example.main.main(main.java:29)

 

[DonManfred]

You should create a new Thread for a new Issue.

 

[agraham]

The posted error seems to be in findFirst, not findAll
at b4j.example.jyblinkstick._findfirst(jyblinkstick.java:111)
However it looks mispelled. From your posted link it should be findFirst with a capital F