add pscache testcase

src/main/java/com/alibaba/druid/pool/PreparedStatementHolder.java

@@ -36,6 +36,7 @@ public final class PreparedStatementHolder {
     private boolean                    enterOracleImplicitCache = false;
 
     private int                        inUseCount               = 0;
+    private boolean                    pooling                  = false;
 
     public PreparedStatementHolder(PreparedStatementKey key, PreparedStatement stmt){
         this.key = key;
@@ -99,12 +100,21 @@ public final class PreparedStatementHolder {
     public void incrementInUseCount() {
         inUseCount++;
     }
-    
+
     public void decrementInUseCount() {
         inUseCount--;
     }
-    
+
     public int getInUseCount() {
         return inUseCount;
     }
+
+    public boolean isPooling() {
+        return pooling;
+    }
+
+    public void setPooling(boolean pooling) {
+        this.pooling = pooling;
+    }
+
 }

src/main/java/com/alibaba/druid/pool/PreparedStatementPool.java

@@ -57,7 +57,7 @@ public class PreparedStatementPool {
             if (holder.isInUse() && (!dataSource.isSharePreparedStatements())) {
                 return null;
             }
-            
+
             holder.incrementHitCount();
             dataSource.incrementCachedPreparedStatementHitCount();
             if (holder.isEnterOracleImplicitCache()) {
@@ -88,6 +88,7 @@ public class PreparedStatementPool {
 
         PreparedStatementHolder oldHolder = map.put(key, holder);
         if (oldHolder != null && oldHolder != holder) {
+            oldHolder.setPooling(false);
             dataSource.closePreapredStatement(oldHolder);
         } else {
             if (holder.getHitCount() == 0) {
@@ -95,6 +96,7 @@ public class PreparedStatementPool {
             }
         }
 
+        holder.setPooling(true);
     }
 
     public void clear() throws SQLException {
@@ -109,10 +111,11 @@ public class PreparedStatementPool {
     }
 
     private void closeRemovedStatement(PreparedStatementHolder holder) throws SQLException {
+        holder.setPooling(false);
         if (holder.isInUse()) {
             return;
         }
-        
+
         if (holder.isEnterOracleImplicitCache()) {
             OracleUtils.exitImplicitCacheToClose(holder.getStatement());
         }
@@ -125,6 +128,10 @@ public class PreparedStatementPool {
         return map;
     }
 
+    public int size() {
+        return this.map.size();
+    }
+
     public class LRUCache extends LinkedHashMap<PreparedStatementKey, PreparedStatementHolder> {
 
         private static final long serialVersionUID = 1L;