Update Error Prone to 2.0.18

and update errorprone-plugin to 0.0.9.

build.gradle

@@ -10,7 +10,7 @@ buildscript {
         classpath 'org.kordamp:markdown-gradle-plugin:1.0.0'
 		classpath 'org.kordamp.gradle:clirr-gradle-plugin:0.2.0'
 		classpath "org.kt3k.gradle.plugin:coveralls-gradle-plugin:2.3.1"
-		classpath 'net.ltgt.gradle:gradle-errorprone-plugin:0.0.8'
+		classpath 'net.ltgt.gradle:gradle-errorprone-plugin:0.0.9'
     }
 }
 apply plugin: 'org.kordamp.gradle.markdown'
@@ -170,7 +170,7 @@ allprojects {
 	// version 52.0" error messages caused by the errorprone javac.
 	// See https://github.com/tbroyer/gradle-errorprone-plugin/issues/18 for more information.
 	configurations.errorprone {
-		resolutionStrategy.force 'com.google.errorprone:error_prone_core:2.0.15'
+		resolutionStrategy.force 'com.google.errorprone:error_prone_core:2.0.18'
 	}
 }
 

smack-core/src/main/java/org/jivesoftware/smack/AbstractXMPPConnection.java

@@ -1481,6 +1481,7 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
                         getReplyTimeout());
     }
 
+    @SuppressWarnings("FutureReturnValueIgnored")
     @Override
     public void sendStanzaWithResponseCallback(Stanza stanza, final StanzaFilter replyFilter,
                     final StanzaListener callback, final ExceptionCallback exceptionCallback,
@@ -1553,6 +1554,7 @@ public abstract class AbstractXMPPConnection implements XMPPConnection {
         sendStanzaWithResponseCallback(iqRequest, replyFilter, callback, exceptionCallback, timeout);
     }
 
+    @SuppressWarnings("FutureReturnValueIgnored")
     @Override
     public void addOneTimeSyncCallback(final StanzaListener callback, final StanzaFilter packetFilter) {
         final StanzaListener packetListener = new StanzaListener() {

smack-extensions/src/main/java/org/jivesoftware/smackx/pubsub/Node.java

@@ -594,7 +594,7 @@ abstract public class Node
      * 
      * @author Robin Collier
      */
-    public class ItemEventTranslator implements StanzaListener
+    public static class ItemEventTranslator implements StanzaListener
     {
         @SuppressWarnings("rawtypes")
         private ItemEventListener listener;
@@ -623,7 +623,7 @@ abstract public class Node
      * 
      * @author Robin Collier
      */
-    public class ItemDeleteTranslator implements StanzaListener
+    public static class ItemDeleteTranslator implements StanzaListener
     {
         private ItemDeleteListener listener;
 

smack-im/src/test/java/org/jivesoftware/smack/chat/ChatConnectionTest.java

@@ -387,7 +387,7 @@ public class ChatConnectionTest {
         }
     }
 
-    private class TestMessageListener implements ChatMessageListener {
+    private static class TestMessageListener implements ChatMessageListener {
         private Chat msgChat;
         private int counter = 0;
 

smack-jingle-old/src/main/java/org/jivesoftware/smackx/jingleold/mediaimpl/JMFInit.java

@@ -103,6 +103,7 @@ public class JMFInit extends Frame implements Runnable {
         }
     }
 
+    @SuppressWarnings("LiteralClassName")
     private void detectCaptureDevices() {
         // check if JavaSound capture is available
         message("Looking for Audio capturer");

smack-legacy/src/main/java/org/jivesoftware/smackx/workgroup/packet/AgentStatus.java

@@ -38,6 +38,7 @@ import org.xmlpull.v1.XmlPullParserException;
  */
 public class AgentStatus implements ExtensionElement {
 
+    @SuppressWarnings("SimpleDateFormatConstant")
     private static final SimpleDateFormat UTC_FORMAT = new SimpleDateFormat("yyyyMMdd'T'HH:mm:ss");
 
     static {
@@ -206,7 +207,11 @@ public class AgentStatus implements ExtensionElement {
                 buf.append(" userID=\"").append(userID).append('"');
             }
             if (date != null) {
-                buf.append(" startTime=\"").append(UTC_FORMAT.format(date)).append('"');
+                buf.append(" startTime=\"");
+                synchronized (UTC_FORMAT) {
+                    buf.append(UTC_FORMAT.format(date));
+                }
+                buf.append('"');
             }
             if (email != null) {
                 buf.append(" email=\"").append(email).append('"');
@@ -260,7 +265,9 @@ public class AgentStatus implements ExtensionElement {
             String userID = parser.getAttributeValue("", "userID");
             Date date = null;
             try {
-                date = UTC_FORMAT.parse(parser.getAttributeValue("", "startTime"));
+                synchronized (UTC_FORMAT) {
+                    date = UTC_FORMAT.parse(parser.getAttributeValue("", "startTime"));
+                }
             }
             catch (ParseException e) {
             }

smack-legacy/src/main/java/org/jivesoftware/smackx/workgroup/packet/OccupantsInfo.java

@@ -40,6 +40,7 @@ import org.xmlpull.v1.XmlPullParserException;
  */
 public class OccupantsInfo extends IQ {
 
+    @SuppressWarnings("SimpleDateFormatConstant")
     private static final SimpleDateFormat UTC_FORMAT = new SimpleDateFormat("yyyyMMdd'T'HH:mm:ss");
 
     static {
@@ -93,7 +94,9 @@ public class OccupantsInfo extends IQ {
                 buf.append("</name>");
                 // Add the date when the occupant joined the room
                 buf.append("<joined>");
-                buf.append(UTC_FORMAT.format(occupant.getJoined()));
+                synchronized (UTC_FORMAT) {
+                    buf.append(UTC_FORMAT.format(occupant.getJoined()));
+                }
                 buf.append("</joined>");
                 buf.append("</occupant>");
             }
@@ -165,7 +168,9 @@ public class OccupantsInfo extends IQ {
                 } else if ((eventType == XmlPullParser.START_TAG) &&
                         ("joined".equals(parser.getName()))) {
                     try {
-                        joined = UTC_FORMAT.parse(parser.nextText());
+                        synchronized (UTC_FORMAT) {
+                            joined = UTC_FORMAT.parse(parser.nextText());
+                        }
                     } catch (ParseException e) {
                         throw new SmackException(e);
                     }

smack-legacy/src/main/java/org/jivesoftware/smackx/workgroup/packet/Transcripts.java

@@ -36,6 +36,7 @@ import org.jxmpp.jid.Jid;
  */
 public class Transcripts extends IQ {
 
+    @SuppressWarnings("SimpleDateFormatConstant")
     private static final SimpleDateFormat UTC_FORMAT = new SimpleDateFormat("yyyyMMdd'T'HH:mm:ss");
     static {
         UTC_FORMAT.setTimeZone(TimeZone.getTimeZone("GMT+0"));
@@ -169,10 +170,18 @@ public class Transcripts extends IQ {
                     .append("\">");
 
             if (joinTime != null) {
-                buf.append("<joinTime>").append(UTC_FORMAT.format(joinTime)).append("</joinTime>");
+                buf.append("<joinTime>");
+                synchronized (UTC_FORMAT) {
+                    buf.append(UTC_FORMAT.format(joinTime));
+                }
+                buf.append("</joinTime>");
             }
             if (leftTime != null) {
-                buf.append("<leftTime>").append(UTC_FORMAT.format(leftTime)).append("</leftTime>");
+                buf.append("<leftTime>");
+                synchronized (UTC_FORMAT) {
+                    buf.append(UTC_FORMAT.format(leftTime));
+                }
+                buf.append("</leftTime>");
             }
             buf.append("<agents>");
             for (AgentDetail agentDetail : agentDetails) {
@@ -234,10 +243,18 @@ public class Transcripts extends IQ {
                 buf.append("<agentJID>").append(agentJID).append("</agentJID>");
             }
             if (joinTime != null) {
-                buf.append("<joinTime>").append(UTC_FORMAT.format(joinTime)).append("</joinTime>");
+                buf.append("<joinTime>");
+                synchronized (UTC_FORMAT) {
+                    buf.append(UTC_FORMAT.format(joinTime));
+                }
+                buf.append("</joinTime>");
             }
             if (leftTime != null) {
-                buf.append("<leftTime>").append(UTC_FORMAT.format(leftTime)).append("</leftTime>");
+                buf.append("<leftTime>");
+                synchronized (UTC_FORMAT) {
+                    buf.append(UTC_FORMAT.format(leftTime));
+                }
+                buf.append("</leftTime>");
             }
             buf.append("</agent>");
 

smack-legacy/src/main/java/org/jivesoftware/smackx/workgroup/packet/TranscriptsProvider.java

@@ -38,6 +38,7 @@ import java.util.TimeZone;
  */
 public class TranscriptsProvider extends IQProvider<Transcripts> {
 
+    @SuppressWarnings("SimpleDateFormatConstant")
     private static final SimpleDateFormat UTC_FORMAT = new SimpleDateFormat("yyyyMMdd'T'HH:mm:ss");
     static {
         UTC_FORMAT.setTimeZone(TimeZone.getTimeZone("GMT+0"));
@@ -79,12 +80,16 @@ public class TranscriptsProvider extends IQProvider<Transcripts> {
             if (eventType == XmlPullParser.START_TAG) {
                 if (parser.getName().equals("joinTime")) {
                     try {
-                        joinTime = UTC_FORMAT.parse(parser.nextText());
+                        synchronized (UTC_FORMAT) {
+                            joinTime = UTC_FORMAT.parse(parser.nextText());
+                        }
                     } catch (ParseException e) {}
                 }
                 else if (parser.getName().equals("leftTime")) {
                     try {
-                        leftTime = UTC_FORMAT.parse(parser.nextText());
+                        synchronized (UTC_FORMAT) {
+                            leftTime = UTC_FORMAT.parse(parser.nextText());
+                        }
                     } catch (ParseException e) {}
                 }
                 else if (parser.getName().equals("agents")) {
@@ -116,12 +121,16 @@ public class TranscriptsProvider extends IQProvider<Transcripts> {
                 }
                 else if (parser.getName().equals("joinTime")) {
                     try {
-                        joinTime = UTC_FORMAT.parse(parser.nextText());
+                        synchronized (UTC_FORMAT) {
+                            joinTime = UTC_FORMAT.parse(parser.nextText());
+                        }
                     } catch (ParseException e) {}
                 }
                 else if (parser.getName().equals("leftTime")) {
                     try {
-                        leftTime = UTC_FORMAT.parse(parser.nextText());
+                        synchronized (UTC_FORMAT) {
+                            leftTime = UTC_FORMAT.parse(parser.nextText());
+                        }
                     } catch (ParseException e) {}
                 }
                 else if (parser.getName().equals("agent")) {

smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java

@@ -681,6 +681,7 @@ public class XMPPTCPConnection extends AbstractXMPPConnection {
      * @throws SmackException 
      * @throws Exception if an exception occurs.
      */
+    @SuppressWarnings("LiteralClassName")
     private void proceedTLSReceived() throws NoSuchAlgorithmException, CertificateException, IOException, KeyStoreException, NoSuchProviderException, UnrecoverableKeyException, KeyManagementException, SmackException {
         SSLContext context = this.config.getCustomSSLContext();
         KeyStore ks = null;
@@ -1710,6 +1711,7 @@ public class XMPPTCPConnection extends AbstractXMPPConnection {
      * @return the previous listener for this stanza ID or null.
      * @throws StreamManagementNotEnabledException if Stream Management is not enabled.
      */
+    @SuppressWarnings("FutureReturnValueIgnored")
     public StanzaListener addStanzaIdAcknowledgedListener(final String id, StanzaListener listener) throws StreamManagementNotEnabledException {
         // Prevent users from adding callbacks that will never get removed
         if (!smWasEnabledAtLeastOnce) {

smack-tcp/src/test/java/org/jivesoftware/smack/tcp/PacketWriterTest.java

@@ -103,7 +103,7 @@ public class PacketWriterTest {
         }
     }
 
-    public class BlockingStringWriter extends Writer {
+    public static class BlockingStringWriter extends Writer {
         @Override
         @SuppressWarnings("WaitNotInLoop")
         public void write(char[] cbuf, int off, int len) throws IOException {