Java - 检查文件是否在打印队列/正在使用中

Question

好的我有一个程序:

1. 根据用户输入创建临时文件
2. 打印文件(可选)
3. 删除文件(可选)

我的问题在第2和第3阶段之间,我需要等待文件完成打印,直到我可以删除它.

仅供参考:打印需要5-10分钟(在旧计算机上打印大文件)

所以我需要从Java能够检查是否:

• defualt打印队列是空的

• 文件正在使用中(注意:File.canWrite()在打印时返回true)

Answer 1

你检查过Java Print API吗？来自http://download.oracle.com/javase/1.4.2/docs/api/javax/print/event/PrintJobListener.html:

公共界面

PrintJobListener

应将此侦听器接口的实现附加到DocPrintJob以监视打印机作业的状态.

我想你可以提交一份打印作业,然后通过它来监控它的状态.

还有一个相当完整的例子exampledepot.com/egs/javax.print/WaitForDone.html:(注意:URL似乎已经改变,并指向潜在的恶意软件)

try {
    // Open the image file
    InputStream is = new BufferedInputStream(
        new FileInputStream("filename.gif"));
    // Create the print job
    DocPrintJob job = service.createPrintJob();
    Doc doc = new SimpleDoc(is, flavor, null);

    // Monitor print job events
    PrintJobWatcher pjDone = new PrintJobWatcher(job);

    // Print it
    job.print(doc, null);

    // Wait for the print job to be done
    pjDone.waitForDone();

    // It is now safe to close the input stream
    is.close();
} catch (PrintException e) {
} catch (IOException e) {
}

class PrintJobWatcher {
    // true iff it is safe to close the print job's input stream
    boolean done = false;

    PrintJobWatcher(DocPrintJob job) {
        // Add a listener to the print job
        job.addPrintJobListener(new PrintJobAdapter() {
            public void printJobCanceled(PrintJobEvent pje) {
                allDone();
            }
            public void printJobCompleted(PrintJobEvent pje) {
                allDone();
            }
            public void printJobFailed(PrintJobEvent pje) {
                allDone();
            }
            public void printJobNoMoreEvents(PrintJobEvent pje) {
                allDone();
            }
            void allDone() {
                synchronized (PrintJobWatcher.this) {
                    done = true;
                    PrintJobWatcher.this.notify();
                }
            }
        });
    }
    public synchronized void waitForDone() {
        try {
            while (!done) {
                wait();
            }
        } catch (InterruptedException e) {
        }
    }
}