Deploying in a Headless Environment

Deploying in a Headless Environment

A headless environment is one where the hosting workstation or server does not support a display device. Version 1.4 and later of the Java 2 SDK supports headless mode.

You can deploy your ICEbrowser application in a headless environment for tasks such as server side printing and web crawling.

Note: To render HTML pages in a headless environment, you must use ICEbrowser in Swing toolkit mode - stormBase.setComponentToolkitName("swing").

To run in a headless environment, you must set the following Java system property on the command line:

-Djava.awt.headless=true

The following system properties can be useful in a headless environment:

Property

Usage

ice.pilots.html4.printBackgrounds.iTextMode

If you are printing HTML4 content to the IText PDF library, and if background tiled images are contained in the source, set this system property to true to reduce the size of the resulting PDF file.

For more information on the IText library, see http://www.lowagie.com/iText/

ice.storm.use14

To enable JDK 1.4 image loading, which improves image loading in a headless environment, set this property to true.

ice.pilots.html4.addonFontProviders

Set this system property to ice.pilots.html4.FractionalDeviceFontProvider to configure a Java Font Provider which uses fractional font metrics for layout calculations. This provides more accurate font rendering for off-screen devices.

ice.pilots.html4.fractionalMetrics

Set this system property to VALUE_FRACTIONALMETRICS_ON to enable fractional font metric support. Note that the ice.pilots.html4.FractionalDeviceFontProvider must also be configured. This provides more accurate font rendering for off-screen devices.

See HTML to PDF Example for an example of using ICEbrowser in a headless environment.

Property	Usage
ice.pilots.html4.printBackgrounds.iTextMode	If you are printing HTML4 content to the IText PDF library, and if background tiled images are contained in the source, set this system property to true to reduce the size of the resulting PDF file. For more information on the IText library, see http://www.lowagie.com/iText/
ice.storm.use14	To enable JDK 1.4 image loading, which improves image loading in a headless environment, set this property to true.
ice.pilots.html4.addonFontProviders	Set this system property to ice.pilots.html4.FractionalDeviceFontProvider to configure a Java Font Provider which uses fractional font metrics for layout calculations. This provides more accurate font rendering for off-screen devices.
ice.pilots.html4.fractionalMetrics	Set this system property to VALUE_FRACTIONALMETRICS_ON to enable fractional font metric support. Note that the ice.pilots.html4.FractionalDeviceFontProvider must also be configured. This provides more accurate font rendering for off-screen devices.