checkpoint

[sbp.git] / src / edu / berkeley / sbp / misc / ParserServlet.java

diff --git a/src/edu/berkeley/sbp/misc/ParserServlet.java b/src/edu/berkeley/sbp/misc/ParserServlet.java
new file mode 100644 (file)
index 0000000..47f8e58
--- /dev/null
+++ b/src/edu/berkeley/sbp/misc/ParserServlet.java
@@ -0,0 +1,75 @@
+package edu.berkeley.sbp.misc;
+import edu.berkeley.sbp.util.*;
+import edu.berkeley.sbp.*;
+import edu.berkeley.sbp.chr.*;
+import java.util.*;
+import java.io.*;
+import javax.servlet.*;
+import javax.servlet.http.*;
+import java.io.*;
+import java.net.*;
+import java.util.*;
+
+public class ParserServlet extends HttpServlet {
+
+    public void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException {
+        doPost(req, resp);
+    }
+    public void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException {
+        try {
+        try {
+            System.out.println("a");
+           
+            Tree<String> gram =
+                new CharParser(MetaGrammar.make()).parse(new StringReader(req.getParameter("grammar").trim())).expand1();
+            System.out.println("b");
+            MetaGrammar g = (MetaGrammar)new MetaGrammar().walk(gram);
+            Union meta = g.done();
+            Forest<String> out = new CharParser(meta).parse(new StringReader(req.getParameter("input").trim()));
+            System.out.println(out);
+            
+            final GraphViz gv = new GraphViz();
+            out.toGraphViz(gv);
+
+            resp.setContentType("image/svg+xml");
+            final Process proc = Runtime.getRuntime().exec(new String[] { "dot", "-Tsvg" });
+            new Thread() {
+                public void run() {
+                    try {
+                        PrintWriter pw = new PrintWriter(new OutputStreamWriter(proc.getOutputStream()));
+                        gv.dump(pw);
+                        pw.flush();
+                        pw.close();
+                    } catch (Exception e) {
+                        e.printStackTrace(); 
+                   }
+                }
+            }.start();
+
+            byte[] buf = new byte[1024];
+            InputStream is = proc.getInputStream();
+            OutputStream os = resp.getOutputStream();
+
+            while(true) {
+                int numread = is.read(buf, 0, buf.length);
+                if (numread==-1) break;
+                os.write(buf, 0, numread);
+            }
+            os.flush();
+            os.close();
+
+        } catch (ParseFailed e) {
+            e.printStackTrace();
+            resp.setContentType("text/plain");
+            PrintWriter pw = new PrintWriter(new OutputStreamWriter(resp.getOutputStream()));
+            pw.println(e);
+            pw.flush();
+            pw.close();
+        }
+        
+        } catch (Exception e) {
+            throw new ServletException(e);
+        }
+    }
+
+}