[SOLVED] java.lang.IllegalAccessError JME 3.4.0alpha6 + Lemur

Ali_RS · April 5, 2021, 3:20pm

Hi

After switching to JME v3.4.0-alpha6 I am getting this error when using Lemur

java.lang.IllegalAccessError: class com.simsilica.lemur.event.KeyAction tried to access private method 'void com.jme3.input.KeyNames.<init>()' (com.simsilica.lemur.event.KeyAction and com.jme3.input.KeyNames are in unnamed module of loader 'app')
	at com.simsilica.lemur.event.KeyAction.<clinit>(KeyAction.java:52) ~[lemur-1.15.0-SNAPSHOT.jar:?]
	at com.simsilica.lemur.component.TextEntryComponent.<clinit>(TextEntryComponent.java:106) ~[lemur-1.15.0-SNAPSHOT.jar:?]
	at com.simsilica.lemur.TextField.createTextEntryComponent(TextField.java:130) ~[lemur-1.15.0-SNAPSHOT.jar:?]
	at com.simsilica.lemur.TextField.setDocumentModel(TextField.java:123) ~[lemur-1.15.0-SNAPSHOT.jar:?]
	at com.simsilica.lemur.TextField.<init>(TextField.java:109) ~[lemur-1.15.0-SNAPSHOT.jar:?]
	at com.simsilica.lemur.TextField.<init>(TextField.java:73) ~[lemur-1.15.0-SNAPSHOT.jar:?]
	at game.LoginState.initialize(LoginState.java:167) ~[main/:?]
	at com.jme3.app.state.BaseAppState.initialize(BaseAppState.java:132) ~[jme3-core-3.4.0-alpha6.jar:3.4.0-alpha6]
	at com.jme3.app.state.AppStateManager.initializePending(AppStateManager.java:316) ~[jme3-core-3.4.0-alpha6.jar:3.4.0-alpha6]
	at com.jme3.app.state.AppStateManager.update(AppStateManager.java:346) ~[jme3-core-3.4.0-alpha6.jar:3.4.0-alpha6]
	at com.jme3.app.SimpleApplication.update(SimpleApplication.java:254) ~[jme3-core-3.4.0-alpha6.jar:3.4.0-alpha6]
	at com.jme3.system.lwjgl.LwjglAbstractDisplay.runLoop(LwjglAbstractDisplay.java:160) ~[jme3-lwjgl-3.4.0-alpha6.jar:3.4.0-alpha6]
	at com.jme3.system.lwjgl.LwjglDisplay.runLoop(LwjglDisplay.java:196) ~[jme3-lwjgl-3.4.0-alpha6.jar:3.4.0-alpha6]
	at com.jme3.system.lwjgl.LwjglAbstractDisplay.run(LwjglAbstractDisplay.java:242) ~[jme3-lwjgl-3.4.0-alpha6.jar:3.4.0-alpha6]
	at java.base/java.lang.Thread.run(Thread.java:832) [?:?]

I noticed KeyNames.java class recently modified (a private no-arg constructor added)

github.com

jMonkeyEngine/jmonkeyengine/blob/1031e03d7249e090a606cd8f2fb5f33f7645a400/jme3-core/src/main/java/com/jme3/input/KeyNames.java#L183-L187


/**
 * A private constructor to inhibit instantiation of this class.
 */
private KeyNames() {
}

in this commit

Seems KeyAction class is instantiating it (for some reason?) here

github.com

jMonkeyEngine-Contributions/Lemur/blob/7ca8f1ee22fedec4979b6548038d3b98efa8b122/src/main/java/com/simsilica/lemur/event/KeyAction.java#L52


*
*  @author    Paul Speed
*/
public class KeyAction {
   /**
    *  @deprecated Use KeyModifiers.CONTROL_DOWN instead.
    */
   @Deprecated
   public static final int CONTROL_DOWN = KeyModifiers.CONTROL_DOWN;
   private static final KeyNames names = new KeyNames();
   private int keyCode;
   private int modifiers;
   public KeyAction( int keyCode, int... modifiers ) {
       this.keyCode = keyCode;
       int m = 0;
       for( int i : modifiers ) {
           m = m | i;
       }

and then using it here

github.com

jMonkeyEngine-Contributions/Lemur/blob/7ca8f1ee22fedec4979b6548038d3b98efa8b122/src/main/java/com/simsilica/lemur/event/KeyAction.java#L99


public int getKeyCode() {
    return keyCode;
}
public boolean hasModifier( int mod ) {
    return (modifiers & mod) == mod;
}
@Override
public String toString() {
    String name = names.getName(keyCode);
    StringBuilder sb = new StringBuilder("KeyAction[");
    if( hasModifier(KeyModifiers.CONTROL_DOWN) ) {
        sb.append( "Control " );
    }
    if( hasModifier(KeyModifiers.SHIFT_DOWN) ) {
        sb.append( "Shift " );
    }
    sb.append(name);
    return sb.toString() + "]";
}

which could/can be replaced by a static method call

github.com

jMonkeyEngine/jmonkeyengine/blob/1031e03d7249e090a606cd8f2fb5f33f7645a400/jme3-core/src/main/java/com/jme3/input/KeyNames.java#L189


        KEY_NAMES[KEY_AX] = "Ax";
        KEY_NAMES[KEY_UNLABELED] = "Unlabeled";
    }
    /**
     * A private constructor to inhibit instantiation of this class.
     */
    private KeyNames() {
    }
    public static String getName(int keyId) {
        return KEY_NAMES[keyId];
    }
}

pspeed · April 5, 2021, 3:27pm

Used to be that there was no static getName() method and so the only way to get them was to instantiate a KeyNames.

It’s unfortunate that this breaking change means that Lemur will not support JME 3.4 for the near to mid future since I’m unable to release new Lemur versions until I take the hours/days that it takes to move to maven central.

I hope perhaps that this can be put back and deprecated instead.

Edit: the commit doesn’t mention an issue number so I’m not sure where to add a comment about putting the constructor back but deprecating it.

pspeed · April 5, 2021, 3:42pm

By the way, if you wanted to submit a PR for Lemur with the change, I will review+apply it as soon as I’m able.

I’ve made a comment on the KeyNames commit hoping we can put the constructor back as deprecated for 3.4… but in the mean time we can fix Lemur for folks who build from source.

Ali_RS · April 5, 2021, 3:43pm

I am submitting one right now

sgold · April 5, 2021, 3:54pm

@Ali_RS thanks for reporting the issue.

I assumed KeyNames had always been a utility class. I’ll remove the constructor for KeyNames to avoid breaking Lemur.

Ali_RS · April 5, 2021, 3:56pm

Submitted a fix for Lemur

pspeed · April 5, 2021, 4:12pm

It should have been… I suspect the original issue was a typo or close to it. I don’t want to speculate about vague memories I have about conversations from that time period so we’ll leave it at that.

A public constructor marked deprecated would at least kick out warnings.

Edit: and note, the non-static getName() goes all the way back to 3.0 or something… 3.1 it was made static, I guess.

Ali_RS · April 5, 2021, 4:34pm

Thank you @sgold

sgold · April 6, 2021, 3:12am

And thanks again to @Ali_RS for testing alpha6 and reporting the issue!

So much easier to deal with it now than during beta…

sgold · April 6, 2021, 7:14am

Please re-test with JME v3.4.0-alpha7.

Ali_RS · April 6, 2021, 7:47am

Just tested it, works fine. Thanks