Utility class to safely do a http POST request.

git-svn-id: https://samskivert.googlecode.com/svn/trunk@1233 6335cc39-0255-0410-8fd6-9bcaacd3b74c

projects/samskivert/src/java/com/samskivert/net/HttpPostUtil.java

@@ -0,0 +1,81 @@
+//
+// $Id: HttpPostUtil.java,v 1.1 2003/09/26 02:36:41 ray Exp $
+
+package com.samskivert.net;
+
+import java.io.BufferedReader;
+import java.io.DataOutputStream;
+import java.io.InputStreamReader;
+import java.io.IOException;
+
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.net.URLEncoder;
+
+import com.samskivert.util.ServiceWaiter;
+
+/**
+ * Contains utility methods for doing a form post.
+ */
+public class HttpPostUtil
+{
+    /**
+     * Return the results of a form post. Note that the http request takes
+     * place on another thread, but this thread blocks until the results
+     * are returned or it times out.
+     *
+     * @param url from which to make the request.
+     * @param submission the entire submission eg "foo=bar&baz=boo&futz=foo".
+     * @param timeout time to wait for the response, in seconds, or -1
+     * for forever.
+     */
+    public static String httpPost (final URL url, final String submission,
+                                   int timeout)
+        throws IOException, ServiceWaiter.TimeoutException
+    {
+        final ServiceWaiter waiter = new ServiceWaiter(
+            (timeout < 0) ? ServiceWaiter.NO_TIMEOUT : timeout);
+        Thread tt = new Thread() {
+            public void run () {
+                try {
+                    HttpURLConnection conn =
+                        (HttpURLConnection) url.openConnection();
+                    conn.setDoInput(true);
+                    conn.setDoOutput(true);
+                    conn.setUseCaches(false);
+                    conn.setRequestProperty(
+                        "Content-Type", "application/x-www-form-urlencoded");
+
+                    DataOutputStream out = new DataOutputStream(
+                        conn.getOutputStream());
+                    out.writeBytes(submission);
+                    out.flush();
+                    out.close();
+
+                    BufferedReader reader = new BufferedReader(
+                        new InputStreamReader(conn.getInputStream()));
+
+                    StringBuffer buf = new StringBuffer();
+                    for (String s; null != (s = reader.readLine()); ) {
+                        buf.append(s);
+                    }
+                    reader.close();
+
+                    waiter.postSuccess(buf.toString()); // yay
+    
+                } catch (IOException e) {
+                    waiter.postFailure(e); // boo
+                }
+            }
+        };
+
+        tt.start();
+
+        if (waiter.waitForResponse()) {
+            return (String) waiter.getArgument();
+
+        } else {
+            throw (IOException) waiter.getArgument();
+        }
+    }
+}