我试图在 headless (headless)环境中运行 Java SWT GUI 应用程序,并问自己是否有 equivalent to the AWT选项 -Djava.awt.headless=true
?
如果没有,我会选择 Xvfb
或 Xvnc
,反正我很好奇。
最佳答案
根据这个非常古老的 bug report SWT headless (headless)模式存在一些问题。但同样它非常古老并且针对 Mac OS 进行了处理。
问答
Asked myself if there is an equivalent to the AWT option "-Djava.awt.headless=true"?
没有这样的属性。尽管在 Win7 和 eclipse 4.2 上,您可以在 headless (headless)模式下操作(只是不要执行 shell.open()
)。
代码
下面的代码打开一个浏览器实例,等待它的加载事件,一旦页面被加载,它就会转储它的页面内容并关闭 shell。此外,它还会在这种 headless (headless)模式下创建颜色和图像。
import org.eclipse.swt.SWT;
import org.eclipse.swt.browser.Browser;
import org.eclipse.swt.browser.LocationEvent;
import org.eclipse.swt.browser.LocationListener;
import org.eclipse.swt.browser.ProgressEvent;
import org.eclipse.swt.browser.ProgressListener;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Image;
import org.eclipse.swt.graphics.ImageData;
import org.eclipse.swt.graphics.ImageLoader;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;
public class HeadLess
{
public static void main(String[] args) {
new HeadLess().start();
}
public void start()
{
Display display = new Display();
final Shell shell = new Shell(display);
shell.setLayout(new GridLayout(1, true));
GridData gridData = new GridData(SWT.FILL, SWT.FILL, true, true);
shell.setLayoutData(gridData);
// Create browser and listen for events in headless mode
final Browser browser = new Browser(shell, SWT.NONE);
gridData = new GridData(SWT.FILL, SWT.FILL, true, true);
browser.setLayoutData(gridData);
browser.setUrl("https://stackoverflow.com/questions/12193231/is-there-an-equivalent-to-java-awt-headless-true-for-swt");
browser.addProgressListener(new ProgressListener() {
public void completed(ProgressEvent event) {
System.out.println(browser.getText());
shell.close();
}
public void changed(ProgressEvent event) {
}
});
browser.addLocationListener(new LocationListener() {
public void changing(LocationEvent event) {
System.out.println(event.location);
}
public void changed(LocationEvent event) {
}
});
// Creating image in headless mode !!
Color red = new Color(display, new RGB(255, 0, 0));
Image image = new Image(display, 100, 100);
GC gc = new GC(image);
gc.setBackground(red);
gc.fillRectangle(image.getBounds());
gc.dispose();
ImageLoader loader = new ImageLoader();
loader.data = new ImageData[] {image.getImageData()};
loader.save("swt.png", SWT.IMAGE_PNG);
red.dispose();
image.dispose();
while (!shell.isDisposed()) {
if (!display.readAndDispatch())
display.sleep();
}
display.dispose();
}
}
附加
关于java - 是否有等同于 "java.awt.headless=true"的 SWT?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/12193231/