runtime.exec

问题 I am trying to get the OutputStream of the Process initiated by exec() to the console. How can this be done? Here is some incomplete code: import java.io.BufferedReader; import java.io.File; import java.io.IOException; import java.io.OutputStream; import java.io.PrintStream; import java.io.Reader; public class RuntimeTests { public static void main(String[] args) { File path = new File(\"C:\\\\Dir\\\\Dir2\"); String command = \"cmd /c dir\"; Reader rdr = null; PrintStream prtStrm = System.out

问题 Hello i have some question about java. here is my code: public static void main(String[] args) throws Exception { Process pr = Runtime.getRuntime().exec(\"java -version\"); BufferedReader in = new BufferedReader(new InputStreamReader(pr.getInputStream())); String line; while ((line = in.readLine()) != null) { System.out.println(line); } pr.waitFor(); System.out.println(\"ok!\"); in.close(); System.exit(0); } in that code i\'am trying to get a java version command execute is ok, but i can\'t

问题 Process p = Runtime.getRuntime().exec(\"sh somescript.sh &> out.txt\"); I am running this command using Java. The script is running but it\'s not redirecting its stream to the file. Moreover, the file out.txt is not getting created. This script runs fine if I run it on shell. Any ideas? 回答1: You need to use ProcessBuilder to redirect. ProcessBuilder builder = new ProcessBuilder("sh", "somescript.sh"); builder.redirectOutput(new File("out.txt")); builder.redirectError(new File("out.txt"));

问题 I tried to make an application that calls an external program that I have to pass two parameters. It doesn\'t give any errors.The program.exe,written in c++, takes a picture and modifies the content of txt file. The java program runs but it does nothing Here is my sample code String[] params = new String [3]; params[0] = \"C:\\\\Users\\\\user\\\\Desktop\\\\program.exe\"; params[1] = \"C:\\\\Users\\\\user\\\\Desktop\\\\images.jpg\"; params[2] = \"C:\\\\Users\\\\user\\\\Desktop\\\\images2.txt\"

问题 Process process = Runtime.getRuntime().exec(\"tasklist\"); BufferedReader reader = new BufferedReader(new InputStreamReader(process.getInputStream())); process.waitFor(); 回答1: There are many reasons that waitFor() doesn't return. But it usually boils down to the fact that the executed command doesn't quit. This, again, can have many reasons. One common reason is that the process produces some output and you don't read from the appropriate streams. This means that the process is blocked as

问题 I\'m trying to execute an external command from java code, but there\'s a difference I\'ve noticed between Runtime.getRuntime().exec(...) and new ProcessBuilder(...).start() . When using Runtime : Process p = Runtime.getRuntime().exec(installation_path + uninstall_path + uninstall_command + uninstall_arguments); p.waitFor(); the exitValue is 0 and the command is terminated ok. However, with ProcessBuilder : Process p = (new ProcessBuilder(installation_path + uninstall_path + uninstall_command

问题 This question already has an answer here: Executing a Java application in a separate process 9 answers Is there a way to run this command line within a Java application? java -jar map.jar time.rel test.txt debug I can run it with command but I couldn\'t do it within Java. 回答1: Runtime rt = Runtime.getRuntime(); Process pr = rt.exec("java -jar map.jar time.rel test.txt debug"); http://docs.oracle.com/javase/7/docs/api/java/lang/Runtime.html 回答2: You can also watch the output like this: final

问题 How am I to execute a command in Java with parameters? I\'ve tried Process p = Runtime.getRuntime().exec(new String[]{\"php\",\"/var/www/script.php -m 2\"}); which doesn\'t work. String[] options = new String[]{\"option1\", \"option2\"}; Runtime.getRuntime().exec(\"command\", options); This doesn\'t work as well, because the m parameter is not specified. 回答1: See if this works (sorry can't test it right now) Runtime.getRuntime().exec(new String[]{"php","/var/www/script.php", "-m", "2"}); 回答2:

问题 When I try to run Runtime.exec(String) , certain commands work, while other commands are executed but fail or do different things than in my terminal. Here is a self-contained test case that demonstrates the effect: public class ExecTest { static void exec(String cmd) throws Exception { Process p = Runtime.getRuntime().exec(cmd); int i; while( (i=p.getInputStream().read()) != -1) { System.out.write(i); } while( (i=p.getErrorStream().read()) != -1) { System.err.write(i); } } public static void

问题 Consider the following code: String commandf = \"ls /etc | grep release\"; try { // Execute the command and wait for it to complete Process child = Runtime.getRuntime().exec(commandf); child.waitFor(); // Print the first 16 bytes of its output InputStream i = child.getInputStream(); byte[] b = new byte[16]; i.read(b, 0, b.length); System.out.println(new String(b)); } catch (IOException e) { e.printStackTrace(); System.exit(-1); } The program\'s output is: /etc: adduser.co When I run from the