减少内存占用

src/main/java/com/alibaba/druid/filter/stat/StatFilter.java

@@ -599,13 +599,13 @@ public class StatFilter extends FilterEventAdapter implements StatFilterMBean {
     }
 
     public JdbcConnectionStat.Entry getConnectionInfo(ConnectionProxy connection) {
-        JdbcConnectionStat.Entry counter = (JdbcConnectionStat.Entry) connection.getAttributes().get(ATTR_NAME_CONNECTION_STAT);
+        JdbcConnectionStat.Entry counter = (JdbcConnectionStat.Entry) connection.getAttribute(ATTR_NAME_CONNECTION_STAT);
 
         if (counter == null) {
             String dataSourceName = connection.getDirectDataSource().getName();
-            connection.getAttributes().put(ATTR_NAME_CONNECTION_STAT,
+            connection.putAttribute(ATTR_NAME_CONNECTION_STAT,
                                            new JdbcConnectionStat.Entry(dataSourceName, connection.getId()));
-            counter = (JdbcConnectionStat.Entry) connection.getAttributes().get(ATTR_NAME_CONNECTION_STAT);
+            counter = (JdbcConnectionStat.Entry) connection.getAttribute(ATTR_NAME_CONNECTION_STAT);
         }
 
         return counter;

src/main/java/com/alibaba/druid/proxy/jdbc/WrapperProxy.java

@@ -1,31 +1,39 @@
-/*
- * Copyright 1999-2011 Alibaba Group Holding Ltd.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.alibaba.druid.proxy.jdbc;
-
-import java.sql.Wrapper;
-import java.util.Map;
-
-/**
- * @author wenshao<szujobs@hotmail.com>
- */
-public interface WrapperProxy extends Wrapper {
-
-    long getId();
-
-    Object getRawObject();
-
-    Map<String, Object> getAttributes();
-}
+/*
+ * Copyright 1999-2011 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.druid.proxy.jdbc;
+
+import java.sql.Wrapper;
+import java.util.Map;
+
+/**
+ * @author wenshao<szujobs@hotmail.com>
+ */
+public interface WrapperProxy extends Wrapper {
+
+    long getId();
+
+    Object getRawObject();
+
+    int getAttributesSize();
+
+    void clearAttributes();
+
+    Map<String, Object> getAttributes();
+
+    Object getAttribute(String key);
+
+    void putAttribute(String key, Object value);
+}

src/main/java/com/alibaba/druid/proxy/jdbc/WrapperProxyImpl.java

@@ -1,82 +1,116 @@
-/*
- * Copyright 1999-2011 Alibaba Group Holding Ltd.
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package com.alibaba.druid.proxy.jdbc;
-
-import java.sql.SQLException;
-import java.sql.Wrapper;
-import java.util.HashMap;
-import java.util.Map;
-
-import com.alibaba.druid.filter.FilterChain;
-
-/**
- * @author wenshao<szujobs@hotmail.com>
- */
-public abstract class WrapperProxyImpl implements WrapperProxy {
-
-    private final Wrapper             raw;
-
-    private final long                id;
-
-    private final Map<String, Object> attributes = new HashMap<String, Object>(4); // 不需要线程安全
-
-    public WrapperProxyImpl(Wrapper wrapper, long id){
-        this.raw = wrapper;
-        this.id = id;
-    }
-
-    public long getId() {
-        return this.id;
-    }
-
-    public Object getRawObject() {
-        return raw;
-    }
-
-    public abstract FilterChain createChain();
-
-    @Override
-    public boolean isWrapperFor(Class<?> iface) throws SQLException {
-        if (iface == null) {
-            return false;
-        }
-
-        if (iface == this.getClass()) {
-            return true;
-        }
-
-        return createChain().isWrapperFor(raw, iface);
-    }
-
-    @SuppressWarnings("unchecked")
-    @Override
-    public <T> T unwrap(Class<T> iface) throws SQLException {
-        if (iface == null) {
-            return null;
-        }
-        
-        if (iface == this.getClass()) {
-            return (T) this;
-        }
-
-        return createChain().unwrap(raw, iface);
-    }
-
-    public Map<String, Object> getAttributes() {
-        return this.attributes;
-    }
-
-}
+/*
+ * Copyright 1999-2011 Alibaba Group Holding Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.alibaba.druid.proxy.jdbc;
+
+import java.sql.SQLException;
+import java.sql.Wrapper;
+import java.util.HashMap;
+import java.util.Map;
+
+import com.alibaba.druid.filter.FilterChain;
+
+/**
+ * @author wenshao<szujobs@hotmail.com>
+ */
+public abstract class WrapperProxyImpl implements WrapperProxy {
+
+    private final Wrapper       raw;
+
+    private final long          id;
+
+    private Map<String, Object> attributes; // 不需要线程安全
+
+    public WrapperProxyImpl(Wrapper wrapper, long id){
+        this.raw = wrapper;
+        this.id = id;
+    }
+
+    public long getId() {
+        return this.id;
+    }
+
+    public Object getRawObject() {
+        return raw;
+    }
+
+    public abstract FilterChain createChain();
+
+    @Override
+    public boolean isWrapperFor(Class<?> iface) throws SQLException {
+        if (iface == null) {
+            return false;
+        }
+
+        if (iface == this.getClass()) {
+            return true;
+        }
+
+        return createChain().isWrapperFor(raw, iface);
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public <T> T unwrap(Class<T> iface) throws SQLException {
+        if (iface == null) {
+            return null;
+        }
+
+        if (iface == this.getClass()) {
+            return (T) this;
+        }
+
+        return createChain().unwrap(raw, iface);
+    }
+    
+    public int getAttributesSize() {
+        if (attributes == null) {
+            return 0;
+        }
+        
+        return attributes.size();
+    }
+    
+    public void clearAttributes() {
+        if (this.attributes == null) {
+            return;
+        }
+        
+        this.attributes.clear();
+    }
+
+    public Map<String, Object> getAttributes() {
+        if (attributes == null) {
+            attributes = new HashMap<String, Object>(4);
+        }
+        return this.attributes;
+    }
+    
+    public void putAttribute(String key, Object value) {
+        if (attributes == null) {
+            attributes = new HashMap<String, Object>(4);
+        }
+        this.attributes.put(key, value);
+    }
+
+    public Object getAttribute(String key){
+        if (attributes == null) {
+            return null;
+        }
+        
+        return this.attributes.get(key);
+    }
+    
+}