如何从Java代码中找到实际显示密度（DPI）？

看来目前有可能从中获取它

java.awt.GraphicsEnvironment

// find the display device of interestfinal GraphicsDevice defaultScreenDevice = GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice();// on OS X, it would be CGraphicsDeviceif (defaultScreenDevice instanceof CGraphicsDevice) {    final CGraphicsDevice device = (CGraphicsDevice) defaultScreenDevice;    // this is the missing correction factor, it's equal to 2 on HiDPI a.k.a. Retina displays    final int scaleFactor = device.getScaleFactor();    // now we can compute the real DPI of the screen    final double realDPI = scaleFactor * (device.getXResolution() + device.getYResolution()) / 2;}