Using JDK7 run sample with a modal dialog like Font2DTest from the jfc folder:
..\JDK7.0b19\bin\java -Xcheck:jni -jar Font2DTest.jar

Steps to reproduce:
1) Open File menu
2) select Print menu item
3) press Cancel button in the appeared dialog

FATAL ERROR in native method: Bad global or local ref passed to JNI
        at sun.awt.windows.WToolkit.eventLoop(Native Method)
        at sun.awt.windows.WToolkit.run(WToolkit.java:285)
        at java.lang.Thread.run(Thread.java:659)

Reproducible always. Not reproducible with JDK6.
Posted Date : 2007-09-27 11:06:44.0

N/A

_endModal() function exits with error code.
Posted Date : 2007-09-27 11:06:44.0

I tracked the crash up to the place where we get the array of active windows in AwtDialog:
void AwtDialog::ModalActivateNextWindow(HWND dialogHWnd,
                                        jobject dialogTarget, jobject dialogPeer){
    JNIEnv *env = (JNIEnv *)JNU_GetEnv(jvm, JNI_VERSION_1_2);
    jlongArray windows = (jlongArray)(env->CallStaticObjectMethod(AwtWindow::wwindowPeerCls, awtWindow::getActiveWindowsMID));

Seem that the AwtWindow::wwindowPeerCls member has Local instead of Global reference as its value. Searching the place where the assignment happens I found: 
Java_sun_awt_windows_WWindowPeer_initIDs(JNIEnv *env, jclass cls)
{
    TRY;
    AwtWindow::wwindowPeerCls = cls;
    AwtWindow::getActiveWindowsMID =...

Should wrap it into GlobalRef before using from the other thread.
Perhaps the change caused that code to be called on a different thread and caused this to happen went into early JDK7 build.
Posted Date : 2008-01-11 17:15:08.0

This needs to be back-ported to JAva6 update 12.