Merge remote-tracking branch 'upstream/master'

src/main/java/com/alibaba/druid/sql/dialect/mysql/parser/MySqlExprParser.java

@@ -253,6 +253,10 @@ public class MySqlExprParser extends SQLExprParser {
             } else if ("COLLATE".equalsIgnoreCase(lexer.stringVal()) && !(expr instanceof SQLIdentifierExpr)) {
                 lexer.nextToken();
 
+                if (lexer.token() == Token.EQ) {
+                    lexer.nextToken();
+                }
+                
                 if (lexer.token() != Token.IDENTIFIER) {
                     throw new ParserException("syntax error");
                 }

src/main/java/com/alibaba/druid/sql/dialect/mysql/visitor/MySqlOutputVisitor.java

@@ -384,6 +384,11 @@ public class MySqlOutputVisitor extends SQLASTOutputVisitor implements MySqlASTV
             print(" CHARACTER SET ");
             print(x.getCharSetName());
         }
+        if (x.getCollate() != null) {
+            print(" COLLATE ");
+            print(x.getCollate());
+        }
+        
         if (x.getCollate() != null) {
             print(" COLLATE ");
             print(x.getCollate());

src/main/java/com/alibaba/druid/sql/parser/SQLExprParser.java

@@ -1371,7 +1371,17 @@ public class SQLExprParser extends SQLParser {
                 charType.setCollate(lexer.stringVal());
                 lexer.nextToken();
             }
+        }else if(identifierEquals("COLLATE")){
+            lexer.nextToken();
+            
+            if (lexer.token() != Token.IDENTIFIER) {
+                throw new ParserException();
+            }
+            
+            charType.setCollate(lexer.stringVal());
+            lexer.nextToken();
         }
+        
         return charType;
     }
 

src/main/java/com/alibaba/druid/support/http/stat/WebAppStat.java

@@ -31,6 +31,7 @@ import java.util.concurrent.locks.ReentrantReadWriteLock;
 import com.alibaba.druid.support.logging.Log;
 import com.alibaba.druid.support.logging.LogFactory;
 import com.alibaba.druid.util.LRUCache;
+import java.util.Collections;
 
 public class WebAppStat {
 
@@ -504,7 +505,7 @@ public class WebAppStat {
 
     public List<Map<String, Object>> getSessionStatDataList() {
         List<Map<String, Object>> sessionStatDataList = new ArrayList<Map<String, Object>>(this.sessionStatMap.size());
-        for (WebSessionStat sessionStat : this.sessionStatMap.values()) {
+        for (WebSessionStat sessionStat : Collections.unmodifiableCollection(this.sessionStatMap.values())) {
             Map<String, Object> sessionStatData = sessionStat.getStatData();
 
             int runningCount = ((Number) sessionStatData.get("RunningCount")).intValue();
@@ -642,7 +643,6 @@ public class WebAppStat {
             }
         } else if (isLinux) {
             osLinuxCount.incrementAndGet();
-
             isAndroid = computeUserAgentAndroid(userAgent);
         } else if (userAgent.indexOf("Symbian") != -1) {
             osSymbianCount.incrementAndGet();