Prefer StringBuilder.append(char) over append(String).

This is the more correct API and also has very minor performance benefits.

src/java/org/jivesoftware/admin/AuthCheckFilter.java

@@ -170,7 +170,7 @@ public class AuthCheckFilter implements Filter {
             buf.append(request.getRequestURI());
             String qs = request.getQueryString();
             if (qs != null) {
-                buf.append("?").append(qs);
+                buf.append('?').append(qs);
             }
         }
         catch (Exception e) {

src/java/org/jivesoftware/database/SchemaManager.java

@@ -385,7 +385,7 @@ public class SchemaManager {
                     }
                     // Ignore comments and blank lines.
                     if (isSQLCommandPart(line)) {
-                        command.append(" ").append(line);
+                        command.append(' ').append(line);
                     }
                     if (line.trim().endsWith(";")) {
                         break;

src/java/org/jivesoftware/openfire/audit/spi/AuditManagerImpl.java

@@ -221,7 +221,7 @@ public class AuditManagerImpl extends BasicModule implements AuditManager {
                 ignoreString.append(username);
             }
             else {
-                ignoreString.append(",").append(username);
+                ignoreString.append(',').append(username);
             }
         }
         JiveGlobals.setProperty("xmpp.audit.ignore", ignoreString.toString());

src/java/org/jivesoftware/openfire/clearspace/ClearspaceVCardTranslator.java

@@ -960,7 +960,7 @@ class ClearspaceVCardTranslator {
     private void translateAddressField(Element addressElement, String vCardFieldName, String fieldName, StringBuilder sb) {
         String field = addressElement.elementTextTrim(vCardFieldName);
         if (field != null && !"".equals(field)) {
-            sb.append(fieldName).append(":").append(field).append(",");
+            sb.append(fieldName).append(':').append(field).append(',');
         }
     }
 

src/java/org/jivesoftware/openfire/container/PluginServlet.java

@@ -547,7 +547,7 @@ public class PluginServlet extends HttpServlet {
         for (URL url : pluginClassloader.getURLs()) {
             File file = new File(url.getFile());
 
-            classpath.append(file.getAbsolutePath()).append(";");
+            classpath.append(file.getAbsolutePath()).append(';');
         }
 
         // Load all jars from lib
@@ -568,7 +568,7 @@ public class PluginServlet extends HttpServlet {
         classpath.append(openfireLib.getAbsolutePath()).append("//jasper-runtime.jar;");
 
         if (pluginEnv.getClassesDir() != null) {
-            classpath.append(pluginEnv.getClassesDir().getAbsolutePath()).append(";");
+            classpath.append(pluginEnv.getClassesDir().getAbsolutePath()).append(';');
         }
         return classpath.toString();
     }

src/java/org/jivesoftware/openfire/http/FlashCrossDomainServlet.java

@@ -156,7 +156,7 @@ public class FlashCrossDomainServlet extends HttpServlet {
         }
         if(XMPPServer.getInstance().getConnectionManager().getClientSSLListenerPort() > 0) {
             if(multiple) {
-                builder.append(",");
+                builder.append(',');
             }
             builder.append(XMPPServer.getInstance().getConnectionManager().getClientSSLListenerPort());
             multiple = true;
@@ -166,14 +166,14 @@ public class FlashCrossDomainServlet extends HttpServlet {
             // ports for http-binding may not be strictly needed in here, but it doesn't hurt
             if(HttpBindManager.getInstance().getHttpBindUnsecurePort() > 0) {
                 if(multiple) {
-                    builder.append(",");
+                    builder.append(',');
                 }
                 builder.append(HttpBindManager.getInstance().getHttpBindUnsecurePort());
                 multiple = true;
             }
             if (HttpBindManager.getInstance().isHttpsBindActive()) {
                 if (multiple) {
-                    builder.append(",");
+                    builder.append(',');
                 }
                 builder.append(HttpBindManager.getInstance().getHttpBindSecurePort());
             }

src/java/org/jivesoftware/openfire/ldap/LdapAuthorizationMapping.java

@@ -79,7 +79,7 @@ public class LdapAuthorizationMapping implements AuthorizationMapping {
         princSearchFilter = JiveGlobals.getProperty("ldap.princSearchFilter");
         StringBuilder filter = new StringBuilder();
         if(princSearchFilter == null) {
-            filter.append("(").append(princField).append("={0})");
+            filter.append('(').append(princField).append("={0})");
         } else {
             filter.append("(&(").append(princField).append("={0})(");
             filter.append(princSearchFilter).append("))");

src/java/org/jivesoftware/openfire/ldap/LdapGroupProvider.java

@@ -165,7 +165,7 @@ public class LdapGroupProvider extends AbstractGroupProvider {
         StringBuilder filter = new StringBuilder();
         filter.append("(&");
         filter.append(MessageFormat.format(manager.getGroupSearchFilter(), "*"));
-        filter.append("(").append(key).append("=").append(LdapManager.sanitizeSearchFilter(value));
+        filter.append('(').append(key).append('=').append(LdapManager.sanitizeSearchFilter(value));
         filter.append("))");
         if (Log.isDebugEnabled()) {
             Log.debug("Trying to find group names using query: " + filter.toString());
@@ -191,7 +191,7 @@ public class LdapGroupProvider extends AbstractGroupProvider {
         StringBuilder filter = new StringBuilder();
         // Make the query be a wildcard search by default. So, if the user searches for
         // "Test", make the sanitized search be "Test*" instead.
-        filter.append("(").append(manager.getGroupNameField()).append("=")
+        filter.append('(').append(manager.getGroupNameField()).append('=')
         		.append(LdapManager.sanitizeSearchFilter(query)).append("*)");
         // Perform the LDAP query
         return manager.retrieveList(
@@ -268,9 +268,9 @@ public class LdapGroupProvider extends AbstractGroupProvider {
                             StringBuilder userFilter = new StringBuilder();
                             userFilter.append("(&(");
                             userFilter.append(ldapName.get(ldapName.size() - 1));
-                            userFilter.append(")");
+                            userFilter.append(')');
                             userFilter.append(MessageFormat.format(manager.getSearchFilter(), "*"));
-                            userFilter.append(")");
+                            userFilter.append(')');
                             NamingEnumeration usrAnswer = ctx.search("",
                                     userFilter.toString(), searchControls);
                             if (usrAnswer != null && usrAnswer.hasMoreElements()) {

src/java/org/jivesoftware/openfire/ldap/LdapManager.java

@@ -1191,11 +1191,11 @@ public class LdapManager {
             // Create a correctly-encoded ldap URL for the PROVIDER_URL
             ldapURL.append("ldap://");
             ldapURL.append(host);
-            ldapURL.append(":");
+            ldapURL.append(':');
             ldapURL.append(port);
-            ldapURL.append("/");
+            ldapURL.append('/');
             ldapURL.append(baseDN);
-            ldapURL.append(" ");
+            ldapURL.append(' ');
         }
         return ldapURL.toString();
     }
@@ -1224,7 +1224,7 @@ public class LdapManager {
         this.hosts = hosts;
         StringBuilder hostProperty = new StringBuilder();
         for (String host : hosts) {
-            hostProperty.append(host).append(",");
+            hostProperty.append(host).append(',');
         }
         if (!hosts.isEmpty()) {
             // Remove the last comma
@@ -1604,11 +1604,11 @@ public class LdapManager {
     public String getSearchFilter() {
         StringBuilder filter = new StringBuilder();
         if (searchFilter == null) {
-            filter.append("(").append(usernameField).append("={0})");
+            filter.append('(').append(usernameField).append("={0})");
         }
         else {
             filter.append("(&(").append(usernameField).append("={0})");
-            filter.append(searchFilter).append(")");
+            filter.append(searchFilter).append(')');
         }
         return filter.toString();
     }
@@ -1784,11 +1784,11 @@ public class LdapManager {
     public String getGroupSearchFilter() {
         StringBuilder groupFilter = new StringBuilder();
         if (groupSearchFilter == null) {
-            groupFilter.append("(").append(groupNameField).append("={0})");
+            groupFilter.append('(').append(groupNameField).append("={0})");
         }
         else {
             groupFilter.append("(&(").append(groupNameField).append("={0})");
-            groupFilter.append(groupSearchFilter).append(")");
+            groupFilter.append(groupSearchFilter).append(')');
         }
         return groupFilter.toString();
     }

src/java/org/jivesoftware/openfire/ldap/LdapUserProvider.java

@@ -295,7 +295,7 @@ public class LdapUserProvider implements UserProvider {
         //are returned from the directory
         filter.append("(&(");
         filter.append(MessageFormat.format(manager.getSearchFilter(),"*"));
-        filter.append(")");
+        filter.append(')');
         if (fields.size() > 1) {
             filter.append("(|");
         }
@@ -303,13 +303,13 @@ public class LdapUserProvider implements UserProvider {
             String attribute = searchFields.get(field);
             // Make the query be a wildcard search by default. So, if the user searches for
             // "John", make the sanitized search be "John*" instead.
-            filter.append("(").append(attribute).append("=")
+            filter.append('(').append(attribute).append('=')
             	.append(LdapManager.sanitizeSearchFilter(query)).append("*)");
         }
         if (fields.size() > 1) {
-            filter.append(")");
+            filter.append(')');
         }
-        filter.append(")");
+        filter.append(')');
         List<String> userlist = manager.retrieveList(
                 manager.getUsernameField(),
                 filter.toString(),

src/java/org/jivesoftware/openfire/muc/spi/MultiUserChatServiceImpl.java

@@ -1559,7 +1559,7 @@ public class MultiUserChatServiceImpl implements Component, MultiUserChatService
         for (int i=0; i<array.length; i++) {
             buf.append(array[i]);
             if (i != array.length-1) {
-                buf.append(",");
+                buf.append(',');
             }
         }
         return buf.toString();
@@ -1574,7 +1574,7 @@ public class MultiUserChatServiceImpl implements Component, MultiUserChatService
     private static String fromCollection(Collection<JID> coll) {
         StringBuilder buf = new StringBuilder();
         for (JID elem: coll) {
-            buf.append(elem.toBareJID()).append(",");
+            buf.append(elem.toBareJID()).append(',');
         }
         int endPos = buf.length() > 1 ? buf.length() - 1 : 0;
         return buf.substring(0, endPos);

src/java/org/jivesoftware/openfire/net/DNSUtil.java

@@ -165,11 +165,11 @@ public class DNSUtil {
         StringBuilder sb = new StringBuilder(100);
         for (String key : internalDNS.keySet()) {
             if (sb.length() > 0) {
-                sb.append(",");
+                sb.append(',');
             }
-            sb.append("{").append(key).append(",");
-            sb.append(internalDNS.get(key).getHost()).append(":");
-            sb.append(internalDNS.get(key).getPort()).append("}");
+            sb.append('{').append(key).append(',');
+            sb.append(internalDNS.get(key).getHost()).append(':');
+            sb.append(internalDNS.get(key).getPort()).append('}');
         }
         return sb.toString();
     }

src/java/org/jivesoftware/openfire/net/SASLAuthentication.java

@@ -722,7 +722,7 @@ public class SASLAuthentication {
         reply.append("<success xmlns=\"urn:ietf:params:xml:ns:xmpp-sasl\"");
         if (successData != null) {
             String successData_b64 = StringUtils.encodeBase64(successData).trim();
-            reply.append(">").append(successData_b64).append("</success>");
+            reply.append('>').append(successData_b64).append("</success>");
         }
         else {
             reply.append("/>");

src/java/org/jivesoftware/openfire/net/SocketReadingMode.java

@@ -259,9 +259,9 @@ abstract class SocketReadingMode {
             sb.append("<stream:stream ");
         }
         sb.append("xmlns:stream=\"http://etherx.jabber.org/streams\" xmlns=\"");
-        sb.append(socketReader.getNamespace()).append("\"");
+        sb.append(socketReader.getNamespace()).append('\"');
         if (socketReader.getExtraNamespaces() != null) {
-            sb.append(" ");
+            sb.append(' ');
             sb.append(socketReader.getExtraNamespaces());
         }
         sb.append(" from=\"");
@@ -271,7 +271,7 @@ abstract class SocketReadingMode {
         sb.append("\" xml:lang=\"");
         sb.append(socketReader.connection.getLanguage());
         sb.append("\" version=\"");
-        sb.append(Session.MAJOR_VERSION).append(".").append(Session.MINOR_VERSION);
+        sb.append(Session.MAJOR_VERSION).append('.').append(Session.MINOR_VERSION);
         sb.append("\">");
         return sb.toString();
     }

src/java/org/jivesoftware/openfire/net/StanzaHandler.java

@@ -582,7 +582,7 @@ public abstract class StanzaHandler {
         sb.append("\" xml:lang=\"");
         sb.append(connection.getLanguage());
         sb.append("\" version=\"");
-        sb.append(Session.MAJOR_VERSION).append(".").append(Session.MINOR_VERSION);
+        sb.append(Session.MAJOR_VERSION).append('.').append(Session.MINOR_VERSION);
         sb.append("\">");
         return sb.toString();
     }

src/java/org/jivesoftware/openfire/nio/XMLLightweightParser.java

@@ -353,7 +353,7 @@ class XMLLightweightParser {
             } else if (status == XMLLightweightParser.HEAD) {
                 if (ch == ' ' || ch == '>') {
                     // Append > to head to allow searching </tag>
-                    head.append(">");
+                    head.append('>');
                     if(ch == '>')
                         status = XMLLightweightParser.OUTSIDE;
                     else

src/java/org/jivesoftware/openfire/pubsub/PubSubModule.java

@@ -756,7 +756,7 @@ public class PubSubModule extends BasicModule implements ServerItemsProvider, Di
         for (int i=0; i<array.length; i++) {
             buf.append(array[i]);
             if (i != array.length-1) {
-                buf.append(",");
+                buf.append(',');
             }
         }
         return buf.toString();

src/java/org/jivesoftware/openfire/pubsub/PubSubPersistenceManager.java

@@ -1818,14 +1818,14 @@ public class PubSubPersistenceManager {
 	private static String encodeWithComma(Collection<String> strings) {
         StringBuilder sb = new StringBuilder(90);
         for (String group : strings) {
-            sb.append(group).append(",");
+            sb.append(group).append(',');
         }
         if (!strings.isEmpty()) {
             sb.setLength(sb.length()-1);
         }
         else {
             // Add a blank so an empty string is never replaced with NULL (oracle...arggg!!!)
-            sb.append(" ");
+            sb.append(' ');
         }
         return sb.toString();
     }

src/java/org/jivesoftware/openfire/pubsub/PublishedItem.java

@@ -308,6 +308,6 @@ public class PublishedItem implements Serializable {
      */
     public static String getItemKey(String nodeId, String itemId) {
     	return new StringBuilder(nodeId)
-    		.append(":").append(itemId).toString();
+    		.append(':').append(itemId).toString();
     }
 }

src/java/org/jivesoftware/openfire/session/LocalClientSession.java

@@ -300,7 +300,7 @@ public class LocalClientSession extends LocalSession implements ClientSession {
         // Don't include version info if the version is 0.0.
         if (majorVersion != 0) {
             sb.append("\" version=\"");
-            sb.append(majorVersion).append(".").append(minorVersion);
+            sb.append(majorVersion).append('.').append(minorVersion);
         }
         sb.append("\">");
         connection.deliverRawText(sb.toString());

src/java/org/jivesoftware/openfire/session/LocalIncomingServerSession.java

@@ -139,7 +139,7 @@ public class LocalIncomingServerSession extends LocalServerSession implements In
             if (serverVersion[0] >= 1) {
                 openingStream.append(" version=\"1.0\">");
             } else {
-                openingStream.append(">");
+                openingStream.append('>');
             }
             
             connection.deliverRawText(openingStream.toString());

src/java/org/jivesoftware/openfire/user/DefaultUserProvider.java

@@ -500,10 +500,10 @@ public class DefaultUserProvider implements UserProvider {
                 sb.delete(0, sb.length());
                 count = 0;
             }
-            sb.append(element).append(",");
+            sb.append(element).append(',');
             count++;
         }
-        sb.append(".");
+        sb.append('.');
         Log.debug(callingMethod + " results: " + sb.toString());
     }
 }

src/java/org/jivesoftware/openfire/user/JDBCUserProvider.java

@@ -319,7 +319,7 @@ public class JDBCUserProvider implements UserProvider {
             sql.append(searchSQL);
             boolean first = true;
             if (fields.contains("Username")) {
-                sql.append(" ");
+                sql.append(' ');
                 sql.append(usernameField);
                 sql.append(" LIKE ?");
                 queries++;
@@ -329,7 +329,7 @@ public class JDBCUserProvider implements UserProvider {
                 if (!first) {
                     sql.append(" AND");
                 }
-                sql.append(" ");
+                sql.append(' ');
                 sql.append(nameField);
                 sql.append(" LIKE ?");
                 queries++;
@@ -339,7 +339,7 @@ public class JDBCUserProvider implements UserProvider {
                 if (!first) {
                     sql.append(" AND");
                 }
-                sql.append(" ");
+                sql.append(' ');
                 sql.append(emailField);
                 sql.append(" LIKE ?");
                 queries++;
@@ -416,10 +416,10 @@ public class JDBCUserProvider implements UserProvider {
                 sb.delete(0, sb.length());
                 count = 0;
             }
-            sb.append(element).append(",");
+            sb.append(element).append(',');
             count++;
         }
-        sb.append(".");
+        sb.append('.');
         Log.debug(callingMethod + " results: " + sb.toString());
     }
 

src/java/org/jivesoftware/util/LocaleUtils.java

@@ -307,7 +307,7 @@ public class LocaleUtils {
             offset += (int)JiveConstants.HOUR;
         }
 
-        buf.append("(");
+        buf.append('(');
         if (offset < 0) {
             buf.append("GMT-");
         }
@@ -317,9 +317,9 @@ public class LocaleUtils {
         offset = Math.abs(offset);
         int hours = offset / (int)JiveConstants.HOUR;
         int minutes = (offset % (int)JiveConstants.HOUR) / (int)JiveConstants.MINUTE;
-        buf.append(hours).append(":");
+        buf.append(hours).append(':');
         if (minutes < 10) {
-            buf.append("0").append(minutes);
+            buf.append('0').append(minutes);
         }
         else {
             buf.append(minutes);

src/java/org/jivesoftware/util/StringUtils.java

@@ -458,7 +458,7 @@ public class StringUtils {
 
         for (i = 0; i < bytes.length; i++) {
             if (((int)bytes[i] & 0xff) < 0x10) {
-                buf.append("0");
+                buf.append('0');
             }
             buf.append(Long.toString((int)bytes[i] & 0xff, 16));
         }
@@ -1010,7 +1010,7 @@ public class StringUtils {
         else if (delta < JiveConstants.HOUR) {
             long mins = delta / JiveConstants.MINUTE;
             StringBuilder sb = new StringBuilder();
-            sb.append(mins).append(" ");
+            sb.append(mins).append(' ');
             sb.append((mins==1) ? LocaleUtils.getLocalizedString("global.minute") : LocaleUtils.getLocalizedString("global.minutes"));
             return sb.toString();
         }
@@ -1019,10 +1019,10 @@ public class StringUtils {
             delta -= hours * JiveConstants.HOUR;
             long mins = delta / JiveConstants.MINUTE;
             StringBuilder sb = new StringBuilder();
-            sb.append(hours).append(" ");
+            sb.append(hours).append(' ');
             sb.append((hours == 1) ? LocaleUtils.getLocalizedString("global.hour") : LocaleUtils.getLocalizedString("global.hours"));
             sb.append(", ");
-            sb.append(mins).append(" ");
+            sb.append(mins).append(' ');
             sb.append((mins == 1) ? LocaleUtils.getLocalizedString("global.minute") : LocaleUtils.getLocalizedString("global.minutes"));
             return sb.toString();
         } else {
@@ -1032,13 +1032,13 @@ public class StringUtils {
             delta -= hours * JiveConstants.HOUR;
             long mins = delta / JiveConstants.MINUTE;
             StringBuilder sb = new StringBuilder();
-            sb.append(days).append(" ");
+            sb.append(days).append(' ');
             sb.append((days == 1) ? LocaleUtils.getLocalizedString("global.day") : LocaleUtils.getLocalizedString("global.days"));
             sb.append(", ");
-            sb.append(hours).append(" ");
+            sb.append(hours).append(' ');
             sb.append((hours == 1) ? LocaleUtils.getLocalizedString("global.hour") : LocaleUtils.getLocalizedString("global.hours"));
             sb.append(", ");
-            sb.append(mins).append(" ");
+            sb.append(mins).append(' ');
             sb.append((mins == 1) ? LocaleUtils.getLocalizedString("global.minute") : LocaleUtils.getLocalizedString("global.minutes"));
             return sb.toString();
         }