其他观察

Question

在Netbeans中，我正在尝试创建一个桌面应用程序，其UI如下所示：

我正在通过Java代码执行“adb logcat命令”，该代码在几秒钟内加载了1000行日志。我打算通过NetBeans中的jTable显示所有这些信息。

使用参数：adb logcat -t 100 - ＆gt;我现在只将日志限制为100行。但是，对于1000行或在删除对行数的限制时，applet变得无响应（或卡在process（）方法中）。

我不确定我是否在代码中正确实现了SwingWorker线程。我正在寻找有关如何改进代码以动态加载大量数据的建议，而不会让applet变得无法响应。

以下是applet实现的代码...包含2个函数：

从applet的init（）方法调用的viewLogs（）。

SwingWorker实现。

    public void viewLogs() throws IOException {

    String[] command = {"CMD","/C", "adb logcat -t 100"};
    ProcessBuilder probuilder = new ProcessBuilder( command );
    probuilder.directory(new File("c:\\Users\\k.garg\\Desktop\\"));
    Process process = probuilder.start();

    InputStream is = process.getInputStream();      
    InputStreamReader isr = new InputStreamReader(is);
    br = new BufferedReader(isr);

    DefaultTableModel model = (DefaultTableModel)jTable1.getModel();
    worker.execute();

    try {
        int exitVal = process.waitFor();
        System.out.println("exitVal = " + exitVal);
    } catch (InterruptedException e) {
        e.printStackTrace();
    }
}
public class TableSwingWorker extends SwingWorker<DefaultTableModel, Object[]>{
private DefaultTableModel tableModel;
public TableSwingWorker(DefaultTableModel tableModel){
    this.tableModel = tableModel;
}

@Override
protected DefaultTableModel doInBackground() throws Exception {
    Thread.sleep(2000); //added for initial UI to load
    System.out.println("Start populating");
    String line, date, time, loglevel, PID, TID, tag, message="";
    String log;
    int count = 0;
    while ((log = br.readLine()) != null) {
        count++;

        String[] splitLog = log.trim().split("\\s+");
        line = Integer.toString(count);
        date = splitLog[0];
        time = splitLog[1];
        PID = splitLog[2];
        TID = splitLog[3];
        loglevel = splitLog[4];
        tag = splitLog[5];
        for(int i=6; i<splitLog.length;i++){
            message += splitLog[i];
        }
        publish(new Object[]{line, date, time, PID, TID, loglevel, tag, message});
    }
    return tableModel;
}

@Override
protected void process(List<Object[]> chunks) {
    System.out.println("Adding " + chunks.size() + " rows");
    for(Object[] row: chunks)
        tableModel.insertRow(0,row);
}

}

Answer 1

关键问题是......

try {
    int exitVal = process.waitFor();
    System.out.println("exitVal = " + exitVal);
} catch (InterruptedException e) {
    e.printStackTrace();
}

这阻止了事件调度线程，阻止在Process完成之前发生任何可能的更新，这有点违背了使用SwingWorker的目的。

您最好直接执行Process中的SwingWorker，例如......

public class TableSwingWorker extends SwingWorker<Integer, Object[]> {

    private DefaultTableModel tableModel;
    private int count;

    public TableSwingWorker(DefaultTableModel tableModel) {
        this.tableModel = tableModel;
    }

    @Override
    protected Integer doInBackground() throws Exception {
        count = 0;

        String[] command = {"CMD", "/C", "adb logcat -t 100"};
        ProcessBuilder probuilder = new ProcessBuilder(command);
        probuilder.directory(new File("c:\\Users\\k.garg\\Desktop\\"));
        Process process = probuilder.start();

        InputConsumer consumer = new InputConsumer(process.getInputStream());
        consumer.start();

        int result = process.waitFor();
        consumer.join();

        return result;
    }

    @Override
    protected void process(List<Object[]> chunks) {
        System.out.println("Adding " + chunks.size() + " rows");
        for (Object[] row : chunks) {
            tableModel.insertRow(0, row);
        }
    }

    protected void processOutput(String text) {
            count++;

            String[] splitLog = text.trim().split("\\s+");
            String line = Integer.toString(count);
            String date = splitLog[0];
            String time = splitLog[1];
            String PID = splitLog[2];
            String TID = splitLog[3];
            String loglevel = splitLog[4];
            String tag = splitLog[5];

            StringBuilder message = new StringBuilder(64);
            for (int i = 6; i < splitLog.length; i++) {
                message.append(splitLog[i]);
            }
            publish(new Object[]{line, date, time, PID, TID, loglevel, tag, message});
    }

    public class InputConsumer extends Thread {

        private InputStream is;

        public InputConsumer(InputStream is) {
            this.is = is;
            start();
        }

        @Override
        public void run() {
            try (BufferedReader br = new BufferedReader(new InputStreamReader(is))) {
                String text = null;
                while ((text = br.readLine()) != null) {
                    processOutput(text);
                }
            } catch (IOException exp) {
                exp.printStackTrace();
            }
        }
    }
}

好吧，这可能看起来有点重＆＃34;但它做了两件重要的事情：

将关闭过程的InputStream加载到另一个Thread，这样我们就可以......
waitFor要退出的流程，以便我们获得退出值，这可用于诊断为什么某些人不时不工作

其他观察

Applet的本质是在严格的安全约束下运行，通常意味着它们不允许在其他机器上执行程序。
Applet也不再支持。有关详细信息，请参阅Java Plugin support deprecated和Moving to a Plugin-Free Web

使用SwingWorker在jTable中动态加载大数据

1 个答案:

其他观察