Improve JingleS5BTransportInfo by introducing abstract class

Introduce a abstract class for shared functionality. And remove static
lazy getters.

smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/elements/JingleS5BTransport.java

@@ -133,19 +133,19 @@ public class JingleS5BTransport extends JingleContentTransport {
         }
 
         public Builder setCandidateUsed(String candidateId) {
-            return setTransportInfo(JingleS5BTransportInfo.CandidateUsed(candidateId));
+            return setTransportInfo(new JingleS5BTransportInfo.CandidateUsed(candidateId));
         }
 
         public Builder setCandidateActivated(String candidateId) {
-            return setTransportInfo(JingleS5BTransportInfo.CandidateActivated(candidateId));
+            return setTransportInfo(new JingleS5BTransportInfo.CandidateActivated(candidateId));
         }
 
         public Builder setCandidateError() {
-            return setTransportInfo(JingleS5BTransportInfo.CandidateError());
+            return setTransportInfo(JingleS5BTransportInfo.CandidateError.INSTANCE);
         }
 
         public Builder setProxyError() {
-            return setTransportInfo(JingleS5BTransportInfo.ProxyError());
+            return setTransportInfo(JingleS5BTransportInfo.ProxyError.INSTANCE);
         }
 
         public JingleS5BTransport build() {

smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/elements/JingleS5BTransportInfo.java

@@ -24,116 +24,76 @@ import org.jivesoftware.smackx.jingle.element.JingleContentTransportInfo;
  */
 public abstract class JingleS5BTransportInfo extends JingleContentTransportInfo {
 
-    private static CandidateError CEI;
+    public static abstract class JingleS5BCandidateTransportInfo extends JingleS5BTransportInfo {
-    private static ProxyError PEI;
-
-    public static CandidateUsed CandidateUsed(String candidateId) {
-        return new CandidateUsed(candidateId);
-    }
-
-    public static CandidateActivated CandidateActivated(String candidateId) {
-        return new CandidateActivated(candidateId);
-    }
-
-    public static CandidateError CandidateError() {
-        if (CEI == null) {
-            CEI = new CandidateError();
-        }
-        return CEI;
-    }
-
-    public static ProxyError ProxyError() {
-        if (PEI == null) {
-            PEI = new ProxyError();
-        }
-        return PEI;
-    }
-
-    public static final class CandidateActivated extends JingleS5BTransportInfo {
-        public static final String ELEMENT = "candidate-activated";
         public static final String ATTR_CID = "cid";
 
         private final String candidateId;
 
+        protected JingleS5BCandidateTransportInfo(String candidateId) {
+            this.candidateId = candidateId;
+        }
+
+        public final String getCandidateId() {
+            return candidateId;
+        }
+
+        @Override
+        public final XmlStringBuilder toXML() {
+            XmlStringBuilder xml = new XmlStringBuilder();
+            xml.halfOpenElement(this);
+            xml.attribute(ATTR_CID, getCandidateId());
+            xml.closeEmptyElement();
+            return xml;
+        }
+
+        @Override
+        public final boolean equals(Object other) {
+            if (!(other instanceof JingleS5BCandidateTransportInfo)) {
+                return false;
+            }
+
+            JingleS5BCandidateTransportInfo otherCandidateTransportInfo = (JingleS5BCandidateTransportInfo) other;
+            return toXML().equals(otherCandidateTransportInfo.toXML());
+        }
+
+        @Override
+        public final int hashCode() {
+            return getCandidateId().hashCode();
+        }
+    }
+
+    public static final class CandidateActivated extends JingleS5BCandidateTransportInfo {
+        public static final String ELEMENT = "candidate-activated";
+
         public CandidateActivated(String candidateId) {
-            this.candidateId = candidateId;
+            super(candidateId);
-        }
-
-        public String getCandidateId() {
-            return candidateId;
         }
 
         @Override
         public String getElementName() {
             return ELEMENT;
         }
-
-        @Override
-        public CharSequence toXML() {
-            XmlStringBuilder xml = new XmlStringBuilder();
-            xml.halfOpenElement(this);
-            xml.attribute(ATTR_CID, candidateId);
-            xml.closeEmptyElement();
-            return xml;
-        }
-
-        @Override
-        public boolean equals(Object other) {
-            return other instanceof CandidateActivated &&
-                    ((CandidateActivated) other).getCandidateId().equals(candidateId);
-        }
-
-        @Override
-        public int hashCode() {
-            return toXML().toString().hashCode();
-        }
     }
 
-    public static final class CandidateUsed extends JingleS5BTransportInfo {
+    public static final class CandidateUsed extends JingleS5BCandidateTransportInfo {
         public static final String ELEMENT = "candidate-used";
-        public static final String ATTR_CID = "cid";
-
-        private final String candidateId;
 
         public CandidateUsed(String candidateId) {
-            this.candidateId = candidateId;
+            super(candidateId);
-        }
-
-        public String getCandidateId() {
-            return candidateId;
         }
 
         @Override
         public String getElementName() {
             return ELEMENT;
         }
-
-        @Override
-        public CharSequence toXML() {
-            XmlStringBuilder xml = new XmlStringBuilder();
-            xml.halfOpenElement(this);
-            xml.attribute(ATTR_CID, candidateId);
-            xml.closeEmptyElement();
-            return xml;
-        }
-
-        @Override
-        public boolean equals(Object other) {
-            return other instanceof CandidateUsed &&
-                    ((CandidateUsed) other).getCandidateId().equals(candidateId);
-        }
-
-        @Override
-        public int hashCode() {
-            return toXML().toString().hashCode();
-        }
     }
 
     public static final class CandidateError extends JingleS5BTransportInfo {
+        public static final CandidateError INSTANCE = new CandidateError();
+
         public static final String ELEMENT = "candidate-error";
 
         private CandidateError() {
-
         }
 
         @Override
@@ -142,7 +102,7 @@ public abstract class JingleS5BTransportInfo extends JingleContentTransportInfo
         }
 
         @Override
-        public CharSequence toXML() {
+        public XmlStringBuilder toXML() {
             XmlStringBuilder xml = new XmlStringBuilder();
             xml.halfOpenElement(this);
             xml.closeEmptyElement();
@@ -151,7 +111,7 @@ public abstract class JingleS5BTransportInfo extends JingleContentTransportInfo
 
         @Override
         public boolean equals(Object other) {
-            return other instanceof CandidateError;
+            return other == INSTANCE;
         }
 
         @Override
@@ -161,10 +121,11 @@ public abstract class JingleS5BTransportInfo extends JingleContentTransportInfo
     }
 
     public static final class ProxyError extends JingleS5BTransportInfo {
+        public static final ProxyError INSTANCE = new ProxyError();
+
         public static final String ELEMENT = "proxy-error";
 
         private ProxyError() {
-
         }
 
         @Override
@@ -182,7 +143,7 @@ public abstract class JingleS5BTransportInfo extends JingleContentTransportInfo
 
         @Override
         public boolean equals(Object other) {
-            return other instanceof ProxyError;
+            return other == INSTANCE;
         }
 
         @Override

smack-extensions/src/main/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/provider/JingleS5BTransportProvider.java

@@ -32,6 +32,7 @@ import org.jivesoftware.smackx.jingle.provider.JingleContentTransportProvider;
 import org.jivesoftware.smackx.jingle.transports.jingle_s5b.elements.JingleS5BTransport;
 import org.jivesoftware.smackx.jingle.transports.jingle_s5b.elements.JingleS5BTransportCandidate;
 import org.jivesoftware.smackx.jingle.transports.jingle_s5b.elements.JingleS5BTransportInfo;
+import org.jivesoftware.smackx.jingle.transports.jingle_s5b.elements.JingleS5BTransportInfo.JingleS5BCandidateTransportInfo;
 
 import org.xmlpull.v1.XmlPullParser;
 
@@ -83,23 +84,23 @@ public class JingleS5BTransportProvider extends JingleContentTransportProvider<J
                             break;
 
                         case JingleS5BTransportInfo.CandidateActivated.ELEMENT:
-                            builder.setTransportInfo(JingleS5BTransportInfo.CandidateActivated(
+                            builder.setTransportInfo(new JingleS5BTransportInfo.CandidateActivated(
                                     parser.getAttributeValue(null,
-                                            JingleS5BTransportInfo.CandidateActivated.ATTR_CID)));
+                                            JingleS5BCandidateTransportInfo.ATTR_CID)));
                             break;
 
                         case JingleS5BTransportInfo.CandidateUsed.ELEMENT:
-                            builder.setTransportInfo(JingleS5BTransportInfo.CandidateUsed(
+                            builder.setTransportInfo(new JingleS5BTransportInfo.CandidateUsed(
                                     parser.getAttributeValue(null,
-                                            JingleS5BTransportInfo.CandidateUsed.ATTR_CID)));
+                                            JingleS5BCandidateTransportInfo.ATTR_CID)));
                             break;
 
                         case JingleS5BTransportInfo.CandidateError.ELEMENT:
-                            builder.setTransportInfo(JingleS5BTransportInfo.CandidateError());
+                            builder.setTransportInfo(JingleS5BTransportInfo.CandidateError.INSTANCE);
                             break;
 
                         case JingleS5BTransportInfo.ProxyError.ELEMENT:
-                            builder.setTransportInfo(JingleS5BTransportInfo.ProxyError());
+                            builder.setTransportInfo(JingleS5BTransportInfo.ProxyError.INSTANCE);
                             break;
                     }
                 }

smack-extensions/src/test/java/org/jivesoftware/smackx/jingle/transports/jingle_s5b/JingleS5BTransportTest.java

@@ -127,7 +127,7 @@ public class JingleS5BTransportTest extends SmackTestSuite {
         assertNull(candidateErrorTransport.getDestinationAddress());
         assertNotNull(candidateErrorTransport.getInfo());
         assertEquals("vj3hs98y", candidateErrorTransport.getStreamId());
-        assertEquals(JingleS5BTransportInfo.CandidateError(),
+        assertEquals(JingleS5BTransportInfo.CandidateError.INSTANCE,
                 candidateErrorTransport.getInfo());
         assertEquals(candidateError, candidateErrorTransport.toXML().toString());
 
@@ -141,7 +141,7 @@ public class JingleS5BTransportTest extends SmackTestSuite {
         assertNotNull(proxyErrorTransport.getInfo());
         assertNotNull(candidateErrorTransport.getInfo());
         assertEquals("vj3hs98y", proxyErrorTransport.getStreamId());
-        assertEquals(JingleS5BTransportInfo.ProxyError(),
+        assertEquals(JingleS5BTransportInfo.ProxyError.INSTANCE,
                 proxyErrorTransport.getInfo());
         assertEquals(proxyError, proxyErrorTransport.toXML().toString());
 
@@ -152,7 +152,7 @@ public class JingleS5BTransportTest extends SmackTestSuite {
         JingleS5BTransport candidateUsedTransport = new JingleS5BTransportProvider()
                 .parse(TestUtils.getParser(candidateUsed));
         assertNotNull(candidateUsedTransport.getInfo());
-        assertEquals(JingleS5BTransportInfo.CandidateUsed("hr65dqyd"),
+        assertEquals(new JingleS5BTransportInfo.CandidateUsed("hr65dqyd"),
                 candidateUsedTransport.getInfo());
         assertEquals("hr65dqyd",
                 ((JingleS5BTransportInfo.CandidateUsed)
@@ -168,7 +168,7 @@ public class JingleS5BTransportTest extends SmackTestSuite {
         assertNotNull(candidateActivatedTransport.getInfo());
         assertNotNull(candidateErrorTransport.getInfo());
 
-        assertEquals(JingleS5BTransportInfo.CandidateActivated("hr65dqyd"),
+        assertEquals(new JingleS5BTransportInfo.CandidateActivated("hr65dqyd"),
                 candidateActivatedTransport.getInfo());
         assertEquals("hr65dqyd",
                 ((JingleS5BTransportInfo.CandidateActivated)