1 files changed, 127 insertions, 0 deletions
diff --git a/src/main/java/fossee/xcos/on/web/SciExec.java b/src/main/java/fossee/xcos/on/web/SciExec.java
new file mode 100644
index 0000000..994d1cd
--- /dev/null
+++ b/src/main/java/fossee/xcos/on/web/SciExec.java
@@ -0,0 +1,127 @@
+package fossee.xcos.on.web;
+
+/**
+ * Servlet code for xcos-on-web Authors: Maverick and Adhitya Description: The
+ * following servlet creates a shell command to run Scilab without any
+ * GUI/simulation window. The diagram sent from client is stored in a
+ * usr-xxx.xcos file and is then simulated. The result is a .png file which is
+ * then sent back to the client.
+ */
+import java.io.*;
+import javax.servlet.*;
+import java.util.*;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.util.ArrayList;
+import java.util.List;
+import org.apache.commons.io.IOUtils;
+import org.apache.commons.io.FilenameUtils;
+
+public class SciExec extends GenericServlet {
+
+    public void service(ServletRequest request, ServletResponse response) throws ServletException, IOException {
+
+        InputStream is = null;
+        ByteArrayOutputStream baos = null;
+        List<String> commands = new ArrayList<String>();
+        /**
+         * Maverick and Srikant: Creating a shell command to run Scilab without
+         * any GUI so that the simulation window doesn't appear.
+         */
+        commands.add("scilab-adv-cli");
+        commands.add("-noatomsautoload");
+        commands.add("-nogui");
+        commands.add("-nb");
+        commands.add("-e");
+
+        String imagePath = "";
+        String fileNameWithoutExt = "";
+
+        /**
+         * Maverick: Ignore the following block.
+         *
+         * commands.add("plot3d();xs2png(gcf(),'img2.png');exit();"); String
+         * data=request.getParameter("name"); pw.println(data);
+         * commands.add("echo "+data+" >
+         * /home/saarang/Softwares/apache-tomcat-8.0.36/webapps/sci/servlet/file.xcos");
+         * commands.add("driver('PNG');xinit('/home/saarang/apache-tomcat-8.0.36/webapps/worknogui/servlet/ans"+k+".png');loadXcosLibs();importXcosDiagram('/home/saarang/apache-tomcat-8.0.36/file.xcos');xcos_simulate(scs_m,4);mode(2);xend();quit();");
+         */
+        ProcessBuilder pb = new ProcessBuilder(commands);
+        try {
+            InputStream inputStream = request.getInputStream();
+            /**
+             * Adhitya: Creating a temporary file in the directory containing
+             * tomcat. This is the .xcos file which will be executed by the
+             * Scilab engine.
+             */
+            File xcosFile = File.createTempFile("usr-", ".xcos");
+            OutputStream outputStream = new FileOutputStream(xcosFile);
+            IOUtils.copy(inputStream, outputStream);
+            outputStream.close();
+
+            String tempPath = xcosFile.getAbsolutePath();
+
+            String parentPath = xcosFile.getParent();
+            fileNameWithoutExt = FilenameUtils.removeExtension(xcosFile.getName());
+
+            /**
+             * Maverick: The resultant .svg file which is produced as a result
+             * of simulation is stored in a different folder inside the
+             * respective webapp directory. The path of the folder is
+             * /path/to/webapp/servlet.
+             *
+             * @ToDo: Modify the following path.
+             */
+            imagePath = parentPath + File.separator + fileNameWithoutExt + ".svg";
+
+            /**
+             * Maverick: Creating the command which is to be executed using
+             * terminal.
+             */
+            commands.add("driver('SVG');xinit('" + imagePath + "');loadXcosLibs();importXcosDiagram('" + tempPath + "');xcos_simulate(scs_m,4);mode(2);xend();quit();");
+
+            /**
+             * Maverick: Reference:
+             * http://stackoverflow.com/questions/23086778/how-to-access-unix-shell-special-variables-using-java
+             * Starting a process to execute the created command.
+             */
+            Process prs = pb.start();
+            is = prs.getInputStream();
+            byte[] b = new byte[1024];
+            int size = 0;
+            baos = new ByteArrayOutputStream();
+            while ((size = is.read(b)) != -1) {
+                baos.write(b, 0, size);
+            }
+            System.out.println(new String(baos.toByteArray()));
+
+        } catch (IOException e) {
+            e.printStackTrace();
+        } catch (Exception e) {
+            System.out.println("Exception");
+        } finally {
+            try {
+                if (is != null) {
+                    is.close();
+                }
+                if (baos != null) {
+                    baos.close();
+                }
+            } catch (Exception ex) {
+            }
+        }
+        /**
+         * Adhitya: Accessing the .svg file and sending it to the client.
+         */
+        OutputStream out = response.getOutputStream();
+        FileInputStream in = new FileInputStream(imagePath);
+        byte[] buffer = new byte[4096];
+        int length;
+        while ((length = in.read(buffer)) > 0) {
+            out.write(buffer, 0, length);
+        }
+        in.close();
+        out.flush();
+    }
+}