---
### Author:  [@tribblesontoast](https://discourse.processing.org/u/tribblesontoast)
#### Post date: [June 2, 2020, 11:29am UTC](https://discourse.processing.org/t/getting-position-from-playnote-minim/21360/6 "2020-06-02T11:29:01Z")
> [@GoToLoop](#):
>
> I can’t find that particular field inside class NoteEvent!:
Apologies, I meant `now`
Before we go any further, I should be more specific.
I’m trying to get the current position of the playNote so that I can sync some visuals to it.
From what I read of `getDeclaredField`, it can’t return the length of an array, but could it get the value of the `now` variable or am I just pushing dust uphill?
---
### Author:  [@GoToLoop](https://discourse.processing.org/u/GoToLoop)
#### Post date: [June 2, 2020, 11:45am UTC](https://discourse.processing.org/t/getting-position-from-playnote-minim/21360/7 "2020-06-02T11:45:09Z")
> [@tribblesontoast](#):
>
> From what I read of **getDeclaredField()**, it can’t return the _length_ of an array,
Method Class::**getDeclaredField()** returns a Field object:
- [Docs.Oracle.com/en/java/javase/11/docs/api/java.base/java/lang/reflect/Field.html](http://Docs.Oracle.com/en/java/javase/11/docs/api/java.base/java/lang/reflect/Field.html)
From there you can read the actual field value by using the correct **get()** method for its datatype.
If it happens to be an array, after you use the correct cast operator on it and store it in an appropriate variable type, you can read its _length_ field.
Regardless, class NoteEvent doesn’t have an array field but rather a HashMap 1.
> [@tribblesontoast](#):
>
> , but could it get the value of the `now` variable…
B/c field _now_ is of datatype `int`, you can easily grab it via method Field::**getInt()** after Field::**setAccessible()**:
- [Docs.Oracle.com/en/java/javase/11/docs/api/java.base/java/lang/reflect/Field.html#getInt(java.lang.Object)](http://Docs.Oracle.com/en/java/javase/11/docs/api/java.base/java/lang/reflect/Field.html#getInt(java.lang.Object))
- [Field (Java SE 11 & JDK 11 )](http://Docs.Oracle.com/en/java/javase/11/docs/api/java.base/java/lang/reflect/Field.html#setAccessible(boolean))
---
### Author:  [@tribblesontoast](https://discourse.processing.org/u/tribblesontoast)
#### Post date: [June 3, 2020, 12:45am UTC](https://discourse.processing.org/t/getting-position-from-playnote-minim/21360/8 "2020-06-03T00:45:21Z")
I’ve tried to get access this way:
`out.noteManager.getClass.getDeclaredField("now");`
but it gives me
`"the field AudioOutput.noteManager is not visible"`
which I expected as that object is private.
So I tried to use
`out.noteManager.setAccessible(true)`
on it, but since it is not a field it doesn’t work and throws the same error.
So i’m guessing I might need to use something like this [stackOverflow solution] ([https://stackoverflow.com/questions/2989560/how-to-get-the-fields-in-an-object-via-reflection](https://stackoverflow.com/questions/2989560/how-to-get-the-fields-in-an-object-via-reflection)) (code from link shown below)in order to get access to the fileds of the AudioOut and then within that, get access to the filelds of the noteManager:
```auto
Object someObject = getItSomehow();
for (Field field : someObject.getClass().getDeclaredFields()) {
field.setAccessible(true); // You might want to set modifier to public first.
Object value = field.get(someObject);
if (value != null) {
System.out.println(field.getName() + "=" + value);
}
}
```
Is this getting closer or have I gone completely haywire?
---
### Author:  [@GoToLoop](https://discourse.processing.org/u/GoToLoop)
#### Post date: [June 3, 2020, 12:49am UTC](https://discourse.processing.org/t/getting-position-from-playnote-minim/21360/9 "2020-06-03T00:49:00Z")
> [@tribblesontoast](#):
>
> Is this getting closer or have I gone completely haywire?
1st, get the Field instance inside a variable, then you can invoke its methods.
---
### Author:  [@GoToLoop](https://discourse.processing.org/u/GoToLoop)
#### Post date: [June 3, 2020, 12:59am UTC](https://discourse.processing.org/t/getting-position-from-playnote-minim/21360/10 "2020-06-03T00:59:56Z")
Field reflection examples from the previous forum:
- [Forum.Processing.org/two/discussion/5274/how-to-get-the-color-from-a-pshape-object#Item\_10](http://Forum.Processing.org/two/discussion/5274/how-to-get-the-color-from-a-pshape-object#Item_10)
- [Forum.Processing.org/two/discussion/9412/how-to-find-a-row-in-a-table#Item\_1](http://Forum.Processing.org/two/discussion/9412/how-to-find-a-row-in-a-table#Item_1)
- [Forum.Processing.org/two/discussion/18119/get-strokeweight-from-pshape#Item\_6](http://Forum.Processing.org/two/discussion/18119/get-strokeweight-from-pshape#Item_6)
- [Forum.Processing.org/two/discussion/16771/accessing-private-variable-inside-a-library-class#Item\_5](http://Forum.Processing.org/two/discussion/16771/accessing-private-variable-inside-a-library-class#Item_5)
---
### Author:  [@tribblesontoast](https://discourse.processing.org/u/tribblesontoast)
#### Post date: [June 3, 2020, 5:35am UTC](https://discourse.processing.org/t/getting-position-from-playnote-minim/21360/11 "2020-06-03T05:35:46Z")
I’ve been looking at your examples, which are so incredibly helpful and I’ve come to this point:
```auto
int i = getNow(out);
static final int getNow(final AudioOutput o) {
try {
final java.lang.reflect.Field f = AudioOutput.class.getDeclaredField("noteManager");
f.setAccessible(true);
final java.lang.reflect.Field fi = f.getClass().getDeclaredField("now");
return fi.getInt(o);
}
catch (ReflectiveOperationException cause) {
throw new RuntimeException(cause);
}
}
```
I must still be a level too high or something as
`getDeclaredField("now")` throws:
`noSuchFieldException: now`
---
### Author:  [@GoToLoop](https://discourse.processing.org/u/GoToLoop)
#### Post date: [June 3, 2020, 6:33pm UTC](https://discourse.processing.org/t/getting-position-from-playnote-minim/21360/12 "2020-06-03T18:33:36Z")
> [@tribblesontoast](#):
>
> noSuchFieldException: now
You’re getting that b/c you’re attempting to grab a field named “now” from a [Field](https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/reflect/Field.html) object; which obviously doesn’t have that:
`fi = f.getClass().getDeclaredField("now");`
Instead you need a NoteManager object 1st, only then you can attempt it.
Invoke method Field::[**get()**](https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/reflect/Field.html#get(java.lang.Object)) over your Field _f_ variable in order to grab the object referenced by AudioOutput::_noteManager_:
`final NoteManager nm = (NoteManager) f.get(o);`
After that you can move forward to get its field NoteManager::_now_ as another Field object:
`final java.lang.reflect.Field fi = NoteManager.class.getDeclaredField("now");`
---
### Author:  [@GoToLoop](https://discourse.processing.org/u/GoToLoop)
#### Post date: [June 3, 2020, 7:07pm UTC](https://discourse.processing.org/t/getting-position-from-playnote-minim/21360/13 "2020-06-03T19:07:34Z")
Since even before you can get ahold of NoteManager::_now_ you 1st need to grab AudioOutput::_noteManager_, that’s not very performant.
How about do that once and cache those 2 objects permanently in some class.
By doing so, we just need the very last reflection step on subsequently calls!
For that I’ve created a class MinimReflectHack inside a “.java” file:
## MinimReflectHack.java:
```auto
/**
* MinimReflectHack (v1.0.3)
* GoToLoop (2020/Jun/03)
* Discourse.Processing.org/t/getting-position-from-playnote-minim/21360/13
*/
package ddf.minim;
import java.lang.reflect.Field;
public class MinimReflectHack {
public static final String NOTE = "noteManager", NOW = "now";
public NoteManager nm;
public Field now;
public MinimReflectHack(AudioOutput out) {
cacheFieldNow(out);
}
public MinimReflectHack cacheFieldNow(AudioOutput out) {
nm = (NoteManager) readField(getField(out, NOTE), out);
now = getField(nm, NOW);
return this;
}
public int getValueNow() {
return readIntField(now, nm);
}
public MinimReflectHack setValueNow(int val) {
writeIntField(now, nm, val);
return this;
}
@Override public String toString() {
return now.toString();
}
public static final Field getField(Object obj, String s) {
return getField(obj.getClass(), s);
}
public static final Field getField(Class c, String s) {
try {
Field f = c.getDeclaredField(s);
f.setAccessible(true);
return f;
}
catch (NoSuchFieldException cause) {
throw new RuntimeException(cause);
}
}
public static final Object readField(Field f, Object obj) {
try {
return f.get(obj);
}
catch (IllegalAccessException cause) {
throw new RuntimeException(cause);
}
}
public static final void writeField(Field f, Object obj, Object val) {
try {
f.set(obj, val);
}
catch (IllegalAccessException cause) {
throw new RuntimeException(cause);
}
}
public static final int readIntField(Field f, Object obj) {
try {
return f.getInt(obj);
}
catch (IllegalAccessException cause) {
throw new RuntimeException(cause);
}
}
public static final void writeIntField(Field f, Object obj, int val) {
try {
f.setInt(obj, val);
}
catch (IllegalAccessException cause) {
throw new RuntimeException(cause);
}
}
public static final float readFloatField(Field f, Object obj) {
try {
return f.getFloat(obj);
}
catch (IllegalAccessException cause) {
throw new RuntimeException(cause);
}
}
public static final void writeFloatField(Field f, Object obj, float val) {
try {
f.setFloat(obj, val);
}
catch (IllegalAccessException cause) {
throw new RuntimeException(cause);
}
}
}
```
There are 2 groups of methods in class MinimReflectHack.
The `static` 1s are general reflection helper functions, which can gets us a Field object, and then read & write to that Field, whether that’s an Object, `int` or `float` datatype.
While the non-`static` 1s are custom handmade to get, read and write to NoteManager::_now_.
Given it’s written as actual Java source code, you’re gonna need to use `import` in order to bring it onto your “.pde” sketch tab:
`import ddf.minim.MinimReflectHack;`
I’ve made my sketch example using “SequenceSound.pde” as its base:
> **[ddf/Minim](https://GitHub.com/ddf/Minim/blob/master/examples/Basics/SequenceSound/SequenceSound.pde)**
>
> A Java audio library, designed to be used with Processing. - ddf/Minim
Here’s my “.pde” test-drive sketch for class _ **ddf.minim.** _MinimReflectHack:
## “MinimSequenceSound.pde”:
```java
/**
* GitHub.com/ddf/Minim/blob/master/
* examples/Basics/SequenceSound/SequenceSound.pde
*/
import ddf.minim.Minim;
import ddf.minim.AudioOutput;
import ddf.minim.AudioBuffer;
AudioOutput out;
AudioBuffer l, r;
int bufSz;
import ddf.minim.MinimReflectHack;
MinimReflectHack hack;
import java.util.Map;
import java.util.List;
Map> events; // NoteManager.NoteEvent is private!
static final float AMP = 100, L_OFF = AMP, R_OFF = AMP + L_OFF;
void settings() {
(out = new Minim(this).getLineOut()).setTempo(80);
hack = new MinimReflectHack(out);
events = (HashMap>) MinimReflectHack.readField(
MinimReflectHack.getField(hack.nm, "events"), hack.nm);
l = out.left;
r = out.right;
bufSz = out.bufferSize();
size(bufSz, round(R_OFF + AMP));
println(width, height, bufSz, ENTER);
println(events);
println(hack, hack.getValueNow(), ENTER);
}
void setup() {
stroke(#FFFF00);
respawnNotes();
}
void draw() {
clear();
surface.setTitle("now: " + hack.getValueNow());
float yl = l.get(0) * AMP + L_OFF;
float yr = r.get(0) * AMP + R_OFF;
int i = 0;
while (++i < bufSz) {
line(i - 1, yl, i, yl = l.get(i) * AMP + L_OFF);
line(i - 1, yr, i, yr = r.get(i) * AMP + R_OFF);
}
}
void mousePressed() {
respawnNotes();
}
void respawnNotes() {
out.pauseNotes();
events.clear();
hack.setValueNow(0);
out.playNote(0.0, 0.9, 97.99);
out.playNote(1.0, 0.9, 123.47);
out.playNote(2.0, 2.9, "C3");
out.playNote(3.0, 1.9, "E3");
out.playNote(4.0, 0.9, "G3");
out.playNote(5.0, "");
out.playNote(6.0, 329.63);
out.playNote(7.0, "G4");
out.setNoteOffset(8.1);
out.playNote("G5");
out.playNote(987.77);
out.resumeNotes();
println(events, ENTER);
println(hack, hack.getValueNow(), ENTER);
}
```
---
### Author:  [@tribblesontoast](https://discourse.processing.org/u/tribblesontoast)
#### Post date: [June 4, 2020, 11:54am UTC](https://discourse.processing.org/t/getting-position-from-playnote-minim/21360/14 "2020-06-04T11:54:06Z")
Thanks for this. I’ll have a play and see what I can do. Your help has been amazing.
Thanks again.
---
### Author:  [@GoToLoop](https://discourse.processing.org/u/GoToLoop)
#### Post date: [June 4, 2020, 4:43pm UTC](https://discourse.processing.org/t/getting-position-from-playnote-minim/21360/15 "2020-06-04T16:43:26Z")
I’m also posting a “Python Mode (Jython)” version, which for a long time is configured to access Java members regardless of their access level.
B/c of that, I’ve completely skipped converting class MinimReflectHack to Python.
After all we need no extra reflection code in order to access AudioOutput::_noteManager_._now_:
```auto
"""
MinimSequenceSound (v1.0.1)
GoToLoop (2020-Jun-04)
Discourse.Processing.org/t/getting-position-from-playnote-minim/21360/14
GitHub.com/ddf/Minim/blob/master/examples/Basics/SequenceSound/SequenceSound.pde
"""
add_library('minim')
AMP = 100.0
L_OFF = AMP
R_OFF = AMP + L_OFF
def settings():
global out, nm, events, l, r, bufSzRange
out = Minim(this).lineOut
nm = out.noteManager
events = nm.events
l = out.left
r = out.right
bufSz = out.bufferSize()
bufSzRange = tuple(range(1, bufSz))
size(bufSz, this.round(R_OFF + AMP))
print width, height, bufSz, ENTER
print events
print nm.now, ENTER
def setup():
stroke(0xffFFFF00)
respawnNotes()
def draw(NOW = 'now: '):
clear()
this.surface.title = NOW + `nm.now`
yl = l.get(0) * AMP + L_OFF
yr = r.get(0) * AMP + R_OFF
ii = 0
for i in bufSzRange:
ly = l.get(i) * AMP + L_OFF
ry = r.get(i) * AMP + R_OFF
line(ii, yl, i, ly)
line(ii, yr, i, ry)
yl = ly
yr = ry
ii = i
def mousePressed(): respawnNotes()
def respawnNotes():
out.pauseNotes()
events.clear()
nm.now = 0
out.playNote(0.0, 0.9, 97.99)
out.playNote(1.0, 0.9, 123.47)
out.playNote(2.0, 2.9, "C3")
out.playNote(3.0, 1.9, "E3")
out.playNote(4.0, 0.9, "G3")
out.playNote(5.0, "")
out.playNote(6.0, 329.63)
out.playNote(7.0, "G4")
out.setNoteOffset(8.1)
out.playNote("G5")
out.playNote(987.77)
out.resumeNotes()
print events, ENTER
print nm.now, ENTER
```