I haven’t done any serious tests with the synchronized method to block instrumentor, but even if everything checks out, there’s still a problem with synchronized native methods. Those have to be instrumented at the call site. I can’t think of a different way. Assume there is a method synchronized native void syncNative(). Then the call
...
syncNative();
...
will have to be changed into
...
synchronized(this) {
syncNative();
}
...
where syncNative is not actually synchronized anymore. Then the synchronized block will have to be instrumented. This is still a different strategy than the one I used before. We’ll see how this goes.
Fortunately, the number of synchronized native methods is relatively small:
class com.sun.java.util.jar.pack.NativeUnpack: initIDs start getNextFile getUnusedInput finish setOption getOption class sun.awt.DebugHelperImpl: printlnImpl printImpl setCTracingOn class sun.awt.image.codec.JPEGImageDecoderImpl: readJPEGStream writeJPEGStream class sun.awt.windows.WDefaultFontCharset: canConvert class sun.awt.windows.WMenuItemPeer: _dispose class sun.awt.windows.WRobotPeer: _dispose() class sun.awt.windows.WScrollPanePeer: setScrollPosition setSpans class java.net.PlainDatagramSocketImpl: bind0 peek peekData receive0 class java.text.Bidi: nativeBidiChars class sun.font.FileFontStrike: getNullScalerContext class sun.awt.windows.WWindowPeer: reshapeFrame class sun.font.Type1Font: getGlyphCode class sun.font.TrueTypeFont: getGlyphPoint class sun.font.FileFont: getNullScaler getFontMetrics getGlyphAdvance getGlyphMetrics getGlyphImage getGlyphOutlineBounds getGlyphOutline getGlyphVectorOutline class sun.font.FontManager: getFontPath setNativeFontPath class sun.awt.windows.WComponentPeer: pShow hide enable disable updateWindow reshape dispose setFont start class java.io.WinNTFileSystem: deleteOnExit class java.io.Win32FileSystem: deleteOnExit class java.lang.Throwable: fillInStackTrace
Ugh. Relatively.
