diff --git a/pom.xml b/pom.xml
index 4a5f84d59e..9276b73df4 100644
--- a/pom.xml
+++ b/pom.xml
@@ -181,7 +181,7 @@
 		<dependency>
 			<groupId>mysql</groupId>
 			<artifactId>mysql-connector-java</artifactId>
-			<version>5.1.12</version>
+			<version>5.0.4</version>
 			<scope>test</scope>
 		</dependency>
 		<dependency>
diff --git a/src/main/java/com/alibaba/druid/mock/MockDriver.java b/src/main/java/com/alibaba/druid/mock/MockDriver.java
index 1af916d37f..41f60439d7 100644
--- a/src/main/java/com/alibaba/druid/mock/MockDriver.java
+++ b/src/main/java/com/alibaba/druid/mock/MockDriver.java
@@ -28,7 +28,6 @@ import java.sql.SQLXML;
 import java.util.Properties;
 import java.util.concurrent.atomic.AtomicLong;
 
-import com.alibaba.druid.jconsole.SQLPanel;
 import com.alibaba.druid.logging.Log;
 import com.alibaba.druid.logging.LogFactory;
 import com.alibaba.druid.mock.handler.MockExecuteHandler;
diff --git a/src/main/java/com/alibaba/druid/proxy/DruidDriver.java b/src/main/java/com/alibaba/druid/proxy/DruidDriver.java
index 4184b8d0a1..362803ad2e 100644
--- a/src/main/java/com/alibaba/druid/proxy/DruidDriver.java
+++ b/src/main/java/com/alibaba/druid/proxy/DruidDriver.java
@@ -31,7 +31,6 @@ import java.util.concurrent.atomic.AtomicLong;
 import com.alibaba.druid.filter.Filter;
 import com.alibaba.druid.logging.Log;
 import com.alibaba.druid.logging.LogFactory;
-import com.alibaba.druid.pool.PoolableStatement;
 import com.alibaba.druid.proxy.config.AbstractDruidFilterConfig;
 import com.alibaba.druid.proxy.config.DruidFilterConfigLoader;
 import com.alibaba.druid.proxy.jdbc.DataSourceProxy;
diff --git a/src/main/java/com/alibaba/druid/proxy/jdbc/DataSourceProxyImpl.java b/src/main/java/com/alibaba/druid/proxy/jdbc/DataSourceProxyImpl.java
index a84114e94d..d8903ca8f0 100644
--- a/src/main/java/com/alibaba/druid/proxy/jdbc/DataSourceProxyImpl.java
+++ b/src/main/java/com/alibaba/druid/proxy/jdbc/DataSourceProxyImpl.java
@@ -15,8 +15,6 @@
  */
 package com.alibaba.druid.proxy.jdbc;
 
-import java.io.PrintWriter;
-import java.io.StringWriter;
 import java.sql.Driver;
 import java.sql.SQLException;
 import java.util.ArrayList;
diff --git a/src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleExprParser.java b/src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleExprParser.java
index f63d820b46..b32835c6b9 100644
--- a/src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleExprParser.java
+++ b/src/main/java/com/alibaba/druid/sql/dialect/oracle/parser/OracleExprParser.java
@@ -21,7 +21,6 @@ import com.alibaba.druid.sql.ast.SQLExpr;
 import com.alibaba.druid.sql.ast.SQLOrderingSpecification;
 import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
 import com.alibaba.druid.sql.ast.expr.SQLIntegerExpr;
-import com.alibaba.druid.sql.ast.expr.SQLMethodInvokeExpr;
 import com.alibaba.druid.sql.ast.expr.SQLNumberExpr;
 import com.alibaba.druid.sql.ast.expr.SQLPropertyExpr;
 import com.alibaba.druid.sql.ast.expr.SQLVariantRefExpr;
diff --git a/src/main/java/com/alibaba/druid/stat/JdbcSqlStat.java b/src/main/java/com/alibaba/druid/stat/JdbcSqlStat.java
index 1e6eda717b..bea4c43943 100644
--- a/src/main/java/com/alibaba/druid/stat/JdbcSqlStat.java
+++ b/src/main/java/com/alibaba/druid/stat/JdbcSqlStat.java
@@ -15,8 +15,6 @@
  */
 package com.alibaba.druid.stat;
 
-import java.io.PrintWriter;
-import java.io.StringWriter;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.Map;
diff --git a/src/main/java/com/alibaba/druid/util/DruidLoaderUtils.java b/src/main/java/com/alibaba/druid/util/DruidLoaderUtils.java
index c20373b657..74eff19f92 100644
--- a/src/main/java/com/alibaba/druid/util/DruidLoaderUtils.java
+++ b/src/main/java/com/alibaba/druid/util/DruidLoaderUtils.java
@@ -23,7 +23,6 @@ import com.alibaba.druid.filter.Filter;
 import com.alibaba.druid.filter.FilterManager;
 import com.alibaba.druid.logging.Log;
 import com.alibaba.druid.logging.LogFactory;
-import com.alibaba.druid.proxy.DruidDriver;
 import com.alibaba.druid.proxy.config.AbstractDruidFilterConfig;
 
 /**
diff --git a/src/main/java/com/alibaba/druid/util/JMXUtils.java b/src/main/java/com/alibaba/druid/util/JMXUtils.java
index caf2e08005..ca8ba8826a 100644
--- a/src/main/java/com/alibaba/druid/util/JMXUtils.java
+++ b/src/main/java/com/alibaba/druid/util/JMXUtils.java
@@ -15,8 +15,6 @@
  */
 package com.alibaba.druid.util;
 
-import java.io.PrintWriter;
-import java.io.StringWriter;
 import java.lang.management.ManagementFactory;
 import java.util.HashMap;
 import java.util.Map;