Enhance performance by correcting malformed UTF-8 characters in request XML.

src/altk/comm/engine/XMLDOMBroadcast.java

@@ -1,9 +1,14 @@
 package altk.comm.engine;
 
 import java.io.ByteArrayInputStream;
+import java.io.CharArrayReader;
 import java.io.IOException;
 import java.io.InputStream;
-import java.io.InputStreamReader;
+import java.nio.ByteBuffer;
+import java.nio.CharBuffer;
+import java.nio.charset.Charset;
+import java.nio.charset.CharsetDecoder;
+import java.nio.charset.CodingErrorAction;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.Vector;
@@ -12,9 +17,6 @@ import java.util.zip.ZipInputStream;
 import javax.servlet.http.HttpServletRequest;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
-import javax.xml.parsers.ParserConfigurationException;
-import javax.xml.parsers.SAXParser;
-import javax.xml.parsers.SAXParserFactory;
 import javax.xml.xpath.XPath;
 import javax.xml.xpath.XPathConstants;
 import javax.xml.xpath.XPathExpressionException;
@@ -27,7 +29,6 @@ import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
 import org.xml.sax.InputSource;
 import org.xml.sax.SAXException;
-import org.xml.sax.helpers.DefaultHandler;
 
 import altk.comm.engine.exception.BroadcastError;
 import altk.comm.engine.exception.BroadcastException;
@@ -100,43 +101,29 @@ public abstract class XMLDOMBroadcast extends Broadcast
             {
                 inb = request.getInputStream();
             }
-            /*
-             // alternate code to find out where are the offending characters in input
-            myLogger.info("Begin parsing");
-            SAXParser parser;
-            try
-            {
-                parser = SAXParserFactory.newInstance().newSAXParser();
-                // constructs an empty ArrayList for use by parser.
-                // Convert InputStream inb into InputSource, using the UTF-8
-                // character set, and for use by SAX parser
-                InputSource is = new InputSource(new InputStreamReader(inb, "UTF-8"));
-                
-                DefaultHandler parserHandler = new DefaultHandler();
-                parser.parse(is, parserHandler);
-            }
-            catch (ParserConfigurationException e)
-            {
-                // TODO Auto-generated catch block
-                e.printStackTrace();
-            }
-            
-            */
+
             int contentLength = request.getContentLength();
             CommonLogger.activity.info("Receiving " + contentLength + " bytes of data");
-            byte[] content = new byte[contentLength];
+            byte[] byteContent = new byte[contentLength];
             int offset = 0;
             int length = contentLength;
             int read;
             while (length > 0)
             {
-                read = inb.read(content, offset, length);
+                read = inb.read(byteContent, offset, length);
                 if (read < 0) break;
                 offset += read;
                 length -= read;
             }
-            CommonLogger.activity.info("Received: " + new String(content, "UTF-8"));                
-            xmlDoc = builder.parse(new ByteArrayInputStream(content), "UTF-8");
+
+            // Clean content off bad UTF-8 characters.
+            Charset utf8Charset = Charset.forName("UTF-8");
+            CharsetDecoder utf8Decoder = utf8Charset.newDecoder();
+            utf8Decoder.onMalformedInput(CodingErrorAction.REPLACE).onUnmappableCharacter(CodingErrorAction.REPLACE);
+            CharBuffer charContent = utf8Decoder.decode(ByteBuffer.wrap(byteContent));
+            CommonLogger.activity.info("Received: " + charContent);                
+            //Do not use this, as it can be killed by non UTF=8 chars: xmlDoc = builder.parse(new ByteArrayInputStream(byteContent), "UTF-8");
+            xmlDoc = builder.parse(new InputSource(new CharArrayReader(charContent.array())));
         }
         catch (SAXException e)
         {
@@ -144,10 +131,9 @@ public abstract class XMLDOMBroadcast extends Broadcast
         }
         catch (IOException e)
         {
-            throw new BroadcastException(BroadcastError.READ_REQUEST_ERROR, "Problem in reading request");
+            throw new BroadcastException(BroadcastError.READ_REQUEST_ERROR, "Problem in reading request: " + e.getMessage());
         }
 
-        //String xpath = "//" + broadcastName; // get all first level elements
         NodeList broadcastNodes = null;
         broadcastNodes = xmlDoc.getElementsByTagName(broadcastType);
         if (broadcastNodes.getLength() == 0)