用java判断打印机打印服务的能力

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import javax.print.DocFlavor;
import javax.print.StreamPrintService;
import javax.print.StreamPrintServiceFactory;
import javax.print.attribute.Attribute;
public class Main {
  public static void main(String[] argv) throws Exception {
    OutputStream fos = new BufferedOutputStream(new FileOutputStream("filename.ps"));
    DocFlavor flavor = DocFlavor.INPUT_STREAM.GIF;
    StreamPrintServiceFactory[] factories = StreamPrintServiceFactory
        .lookupStreamPrintServiceFactories(flavor, DocFlavor.BYTE_ARRAY.POSTSCRIPT.getMimeType());
    StreamPrintService service = factories[0].getPrintService(fos);
    Attribute[] attrs = service.getAttributes().toArray();
    for (int j = 0; j < attrs.length; j++) {
      String attrName = attrs[j].getName();
      String attrValue = attrs[j].toString();
      System.out.println(attrName);
      System.out.println(attrValue);
    }
  }
}