Java 9

Question

我想出了两种方法来解决这个问题，但它们达不到预期。

我使用“进程”执行“ ps -ef”

我可以通过这种方法获取所有行，并且可以通过运行来过滤它们命令。但是如果我有许多相同的命令过程。这是行不通的。
我使用JNA来获取PID



    Field field = null;
    Integer pid = -1;
    try {
        Class clazz = Class.forName("java.lang.UNIXProcess");
        field = clazz.getDeclaredField("pid");
        field.setAccessible(true);
        pid = (Integer) field.get(process);
    } catch (Throwable e) {
        e.printStackTrace();
    }

这种方式只能获取运行窗口的PID。这不是真正的进程PID。

我该怎么办？

谢谢！

Answer 1

Java 9

Java 9引入了一些“不错”的变化，其中之一是包含Process的本机PID-有关更多详细信息，请参见Process#pid

import java.io.IOException;
import java.io.InputStream;

public class Test {

    public static void main(String[] args) throws IOException, InterruptedException {
        ProcessBuilder pb = new ProcessBuilder("/Applications/Xcode.app/Contents/MacOS/Xcode");
        pb.redirectErrorStream(true);
        Process p = pb.start();
        // Yes, I'm a bad developer, but I just want to demonstrate
        // the use of the PID method :/
        new Thread(new Consumer(p.getInputStream())).start();
        System.out.println("PID = " + p.pid());
        p.waitFor();
        System.out.println("Exit with " + p.exitValue());
    }

    public static class Consumer implements Runnable {
        private InputStream is;

        public Consumer(InputStream is) {
            this.is = is;
        }

        @Override
        public void run() {
            try {
                int value = -1;
                while ((value = is.read()) != -1) {
                    // I'm ignoring it for brevity
                }
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }
    }

}

您还可以通过ProcessHandle方法为Process获取对import im.delight.android.webview.AdvancedWebView; public class MainActivity extends AppCompatActivity implements AdvancedWebView.Listener { String ShowOrHideWebViewInitialUse = "show"; private AdvancedWebView mWebView; private ProgressBar spinner; private Boolean exit = false; String currentUrl; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); if (!amIconnected()){ Toast.makeText(getApplicationContext(), "No Internet!", Toast.LENGTH_SHORT).show(); Intent intent= new Intent(this, Main2Activity.class); intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK); startActivity(intent); }else{ mWebView =(AdvancedWebView) findViewById(R.id.webView); mWebView.setWebChromeClient(new WebChromeClient() {}); mWebView.setListener(this, this); spinner = (ProgressBar)findViewById(R.id.progressBar1); mWebView.getSettings().setJavaScriptEnabled(true); mWebView.getSettings().setDomStorageEnabled(true); mWebView.clearCache(true); mWebView.clearHistory(); mWebView.getSettings().setJavaScriptCanOpenWindowsAutomatically(true); mWebView.loadUrl("https://www.example.com"); } } @SuppressLint("NewApi") @Override protected void onResume() { super.onResume(); } @Override protected void onPause() { super.onPause(); } @Override protected void onDestroy() { super.onDestroy(); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent intent) { super.onActivityResult(requestCode, resultCode, intent); mWebView.onActivityResult(requestCode, resultCode, intent); } public void onBackPressed() { if (exit) { finish(); // finish activity }else { Toast.makeText(this, "Press Back again to Exit.", Toast.LENGTH_SHORT).show(); exit = true; new Handler().postDelayed(new Runnable() { @Override public void run() { exit = false; } }, 3* 1000); } } @Override public void onPageStarted(String url, Bitmap favicon) { // show loader while page is loading if (ShowOrHideWebViewInitialUse.equals("show")) { mWebView.setVisibility(mWebView.VISIBLE); spinner.setVisibility(View.VISIBLE); ShowOrHideWebViewInitialUse = "hide"; } currentUrl = url; Log.i("OnpageStarted", "url is " + url); // disable click while loading mWebView.setOnTouchListener(new View.OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { return true; } }); } @Override public void onPageFinished(String url) { // hide loader after page is loaded if (ShowOrHideWebViewInitialUse.equals("hide")){ spinner.setVisibility(View.GONE); mWebView.setVisibility(mWebView.VISIBLE); ShowOrHideWebViewInitialUse = "show"; currentUrl = url; } // enable touch back once page completely loaded mWebView.setOnTouchListener(new View.OnTouchListener() { @Override public boolean onTouch(View v, MotionEvent event) { return false; } }); currentUrl = url; } @Override public void onPageError(int errorCode, String description, String failingUrl) { Toast.makeText(getApplicationContext(), "Something went wrong!", Toast.LENGTH_SHORT).show(); Intent intent= new Intent(MainActivity.this,Main2Activity.class); startActivity(intent); } @Override public void onDownloadRequested(String url, String suggestedFilename, String mimeType, long contentLength, String contentDisposition, String userAgent) { } @Override public void onExternalPageRequest(String url) { } private boolean amIconnected(){ ConnectivityManager connectivityManager = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo(); return activeNetworkInfo != null && activeNetworkInfo.isAvailable() && activeNetworkInfo.isConnected(); }的{{3}}的引用，

如何通过JAVA获取Linux中java.lang.Process的PID

1 个答案:

Java 9