diff --git a/RELEASE-NOTES.md b/RELEASE-NOTES.md
index a9794f9b5c325..5a78591eefd4a 100644
--- a/RELEASE-NOTES.md
+++ b/RELEASE-NOTES.md
@@ -1,3 +1,9 @@
+## 1.5.3
+
+### 缺陷修正
+
+1. [ISSUE #349](https://github.com/dangdangdotcom/sharding-jdbc/issues/349) ResultSet.wasNull功能不正确
+
 ## 1.5.2
 
 ### 里程碑
diff --git a/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/jdbc/core/resultset/ShardingResultSet.java b/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/jdbc/core/resultset/ShardingResultSet.java
index 2ffdb94859eac..bf882ce19abe1 100644
--- a/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/jdbc/core/resultset/ShardingResultSet.java
+++ b/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/jdbc/core/resultset/ShardingResultSet.java
@@ -45,8 +45,6 @@ public final class ShardingResultSet extends AbstractResultSetAdapter {
     
     private final ResultSetMerger mergeResultSet;
     
-    private boolean wasNull;
-    
     public ShardingResultSet(final List<ResultSet> resultSets, final ResultSetMerger mergeResultSet) {
         super(resultSets);
         this.mergeResultSet = mergeResultSet;
@@ -59,370 +57,266 @@ public boolean next() throws SQLException {
     
     @Override
     public boolean wasNull() throws SQLException {
-        return wasNull;
+        return mergeResultSet.wasNull();
     }
     
     @Override
     public boolean getBoolean(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, boolean.class);
-        wasNull = false;
-        return (boolean) ResultSetUtil.convertValue(result, boolean.class);
+        return (boolean) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, boolean.class), boolean.class);
     }
     
     @Override
     public boolean getBoolean(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, boolean.class);
-        wasNull = false;
-        return (boolean) ResultSetUtil.convertValue(result, boolean.class);
+        return (boolean) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, boolean.class), boolean.class);
     }
     
     @Override
     public byte getByte(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, byte.class);
-        wasNull = null == result;
-        return (byte) ResultSetUtil.convertValue(result, byte.class);
+        return (byte) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, byte.class), byte.class);
     }
     
     @Override
     public byte getByte(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, byte.class);
-        wasNull = null == result;
-        return (byte) ResultSetUtil.convertValue(result, byte.class);
+        return (byte) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, byte.class), byte.class);
     }
     
     @Override
     public short getShort(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, short.class);
-        wasNull = null == result;
-        return (short) ResultSetUtil.convertValue(result, short.class);
+        return (short) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, short.class), short.class);
     }
     
     @Override
     public short getShort(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, short.class);
-        wasNull = null == result;
-        return (short) ResultSetUtil.convertValue(result, short.class);
+        return (short) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, short.class), short.class);
     }
     
     @Override
     public int getInt(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, int.class);
-        wasNull = null == result;
-        return (int) ResultSetUtil.convertValue(result, int.class);
+        return (int) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, int.class), int.class);
     }
     
     @Override
     public int getInt(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, int.class);
-        wasNull = null == result;
-        return (int) ResultSetUtil.convertValue(result, int.class);
+        return (int) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, int.class), int.class);
     }
     
     @Override
     public long getLong(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, long.class);
-        wasNull = null == result;
-        return (long) ResultSetUtil.convertValue(result, long.class);
+        return (long) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, long.class), long.class);
     }
     
     @Override
     public long getLong(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, long.class);
-        wasNull = null == result;
-        return (long) ResultSetUtil.convertValue(result, long.class);
+        return (long) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, long.class), long.class);
     }
     
     @Override
     public float getFloat(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, float.class);
-        wasNull = null == result;
-        return (float) ResultSetUtil.convertValue(result, float.class);
+        return (float) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, float.class), float.class);
     }
     
     @Override
     public float getFloat(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, float.class);
-        wasNull = null == result;
-        return (float) ResultSetUtil.convertValue(result, float.class);
+        return (float) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, float.class), float.class);
     }
     
     @Override
     public double getDouble(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, double.class);
-        wasNull = null == result;
-        return (double) ResultSetUtil.convertValue(result, double.class);
+        return (double) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, double.class), double.class);
     }
     
     @Override
     public double getDouble(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, double.class);
-        wasNull = null == result;
-        return (double) ResultSetUtil.convertValue(result, double.class);
+        return (double) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, double.class), double.class);
     }
     
     @Override
     public String getString(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, String.class);
-        wasNull = null == result;
-        return (String) ResultSetUtil.convertValue(result, String.class);
+        return (String) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, String.class), String.class);
     }
     
     @Override
     public String getString(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, String.class);
-        wasNull = null == result;
-        return (String) ResultSetUtil.convertValue(result, String.class);
+        return (String) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, String.class), String.class);
     }
     
     @Override
     public BigDecimal getBigDecimal(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, BigDecimal.class);
-        wasNull = null == result;
-        return (BigDecimal) ResultSetUtil.convertValue(result, BigDecimal.class);
+        return (BigDecimal) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, BigDecimal.class), BigDecimal.class);
     }
     
     @Override
     public BigDecimal getBigDecimal(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, BigDecimal.class);
-        wasNull = null == result;
-        return (BigDecimal) ResultSetUtil.convertValue(result, BigDecimal.class);
+        return (BigDecimal) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, BigDecimal.class), BigDecimal.class);
     }
     
     @Override
     public BigDecimal getBigDecimal(final int columnIndex, final int scale) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, BigDecimal.class);
-        wasNull = null == result;
-        return (BigDecimal) ResultSetUtil.convertValue(result, BigDecimal.class);
+        return (BigDecimal) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, BigDecimal.class), BigDecimal.class);
     }
     
     @Override
     public BigDecimal getBigDecimal(final String columnLabel, final int scale) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, BigDecimal.class);
-        wasNull = null == result;
-        return (BigDecimal) ResultSetUtil.convertValue(result, BigDecimal.class);
+        return (BigDecimal) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, BigDecimal.class), BigDecimal.class);
     }
     
     @Override
     public byte[] getBytes(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, byte[].class);
-        wasNull = null == result;
-        return (byte[]) ResultSetUtil.convertValue(result, byte[].class);
+        return (byte[]) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, byte[].class), byte[].class);
     }
     
     @Override
     public byte[] getBytes(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, byte[].class);
-        wasNull = null == result;
-        return (byte[]) ResultSetUtil.convertValue(result, byte[].class);
+        return (byte[]) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, byte[].class), byte[].class);
     }
     
     @Override
     public Date getDate(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, Date.class);
-        wasNull = null == result;
-        return (Date) ResultSetUtil.convertValue(result, Date.class);
+        return (Date) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, Date.class), Date.class);
     }
     
     @Override
     public Date getDate(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, Date.class);
-        wasNull = null == result;
-        return (Date) ResultSetUtil.convertValue(result, Date.class);
+        return (Date) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, Date.class), Date.class);
     }
     
     @Override
     public Date getDate(final int columnIndex, final Calendar cal) throws SQLException {
-        Object result = mergeResultSet.getCalendarValue(columnIndex, Date.class, cal);
-        wasNull = null == result;
-        return (Date) ResultSetUtil.convertValue(result, Date.class);
+        return (Date) ResultSetUtil.convertValue(mergeResultSet.getCalendarValue(columnIndex, Date.class, cal), Date.class);
     }
     
     @Override
     public Date getDate(final String columnLabel, final Calendar cal) throws SQLException {
-        Object result = mergeResultSet.getCalendarValue(columnLabel, Date.class, cal);
-        wasNull = null == result;
-        return (Date) ResultSetUtil.convertValue(result, Date.class);
+        return (Date) ResultSetUtil.convertValue(mergeResultSet.getCalendarValue(columnLabel, Date.class, cal), Date.class);
     }
     
     @Override
     public Time getTime(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, Time.class);
-        wasNull = null == result;
-        return (Time) ResultSetUtil.convertValue(result, Time.class);
+        return (Time) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, Time.class), Time.class);
     }
     
     @Override
     public Time getTime(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, Time.class);
-        wasNull = null == result;
-        return (Time) ResultSetUtil.convertValue(result, Time.class);
+        return (Time) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, Time.class), Time.class);
     }
     
     @Override
     public Time getTime(final int columnIndex, final Calendar cal) throws SQLException {
-        Object result = mergeResultSet.getCalendarValue(columnIndex, Time.class, cal);
-        wasNull = null == result;
-        return (Time) ResultSetUtil.convertValue(result, Time.class);
+        return (Time) ResultSetUtil.convertValue(mergeResultSet.getCalendarValue(columnIndex, Time.class, cal), Time.class);
     }
     
     @Override
     public Time getTime(final String columnLabel, final Calendar cal) throws SQLException {
-        Object result = mergeResultSet.getCalendarValue(columnLabel, Time.class, cal);
-        wasNull = null == result;
-        return (Time) ResultSetUtil.convertValue(result, Time.class);
+        return (Time) ResultSetUtil.convertValue(mergeResultSet.getCalendarValue(columnLabel, Time.class, cal), Time.class);
     }
             
     @Override
     public Timestamp getTimestamp(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, Timestamp.class);
-        wasNull = null == result;
-        return (Timestamp) ResultSetUtil.convertValue(result, Timestamp.class);
+        return (Timestamp) ResultSetUtil.convertValue(mergeResultSet.getValue(columnIndex, Timestamp.class), Timestamp.class);
     }
     
     @Override
     public Timestamp getTimestamp(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, Timestamp.class);
-        wasNull = null == result;
-        return (Timestamp) ResultSetUtil.convertValue(result, Timestamp.class);
+        return (Timestamp) ResultSetUtil.convertValue(mergeResultSet.getValue(columnLabel, Timestamp.class), Timestamp.class);
     }
     
     @Override
     public Timestamp getTimestamp(final int columnIndex, final Calendar cal) throws SQLException {
-        Object result = mergeResultSet.getCalendarValue(columnIndex, Timestamp.class, cal);
-        wasNull = null == result;
-        return (Timestamp) ResultSetUtil.convertValue(result, Timestamp.class);
+        return (Timestamp) ResultSetUtil.convertValue(mergeResultSet.getCalendarValue(columnIndex, Timestamp.class, cal), Timestamp.class);
     }
     
     @Override
     public Timestamp getTimestamp(final String columnLabel, final Calendar cal) throws SQLException {
-        Object result = mergeResultSet.getCalendarValue(columnLabel, Timestamp.class, cal);
-        wasNull = null == result;
-        return (Timestamp) ResultSetUtil.convertValue(result, Timestamp.class);
+        return (Timestamp) ResultSetUtil.convertValue(mergeResultSet.getCalendarValue(columnLabel, Timestamp.class, cal), Timestamp.class);
     }
     
     @Override
     public InputStream getAsciiStream(final int columnIndex) throws SQLException {
-        InputStream result = mergeResultSet.getInputStream(columnIndex, "Ascii");
-        wasNull = null == result;
-        return result;
+        return mergeResultSet.getInputStream(columnIndex, "Ascii");
     }
     
     @Override
     public InputStream getAsciiStream(final String columnLabel) throws SQLException {
-        InputStream result = mergeResultSet.getInputStream(columnLabel, "Ascii");
-        wasNull = null == result;
-        return result;
+        return mergeResultSet.getInputStream(columnLabel, "Ascii");
     }
     
     @Override
     public InputStream getUnicodeStream(final int columnIndex) throws SQLException {
-        InputStream result = mergeResultSet.getInputStream(columnIndex, "Unicode");
-        wasNull = null == result;
-        return result;
+        return mergeResultSet.getInputStream(columnIndex, "Unicode");
     }
     
     @Override
     public InputStream getUnicodeStream(final String columnLabel) throws SQLException {
-        InputStream result = mergeResultSet.getInputStream(columnLabel, "Unicode");
-        wasNull = null == result;
-        return result;
+        return mergeResultSet.getInputStream(columnLabel, "Unicode");
     }
     
     @Override
     public InputStream getBinaryStream(final int columnIndex) throws SQLException {
-        InputStream result = mergeResultSet.getInputStream(columnIndex, "Binary");
-        wasNull = null == result;
-        return result;
+        return mergeResultSet.getInputStream(columnIndex, "Binary");
     }
     
     @Override
     public InputStream getBinaryStream(final String columnLabel) throws SQLException {
-        InputStream result = mergeResultSet.getInputStream(columnLabel, "Binary");
-        wasNull = null == result;
-        return result;
+        return mergeResultSet.getInputStream(columnLabel, "Binary");
     }
     
     @Override
     public Reader getCharacterStream(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, Reader.class);
-        wasNull = null == result;
-        return (Reader) result;
+        return (Reader) mergeResultSet.getValue(columnIndex, Reader.class);
     }
     
     @Override
     public Reader getCharacterStream(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, Reader.class);
-        wasNull = null == result;
-        return (Reader) result;
+        return (Reader) mergeResultSet.getValue(columnLabel, Reader.class);
     }
     
     @Override
     public Blob getBlob(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, Blob.class);
-        wasNull = null == result;
-        return (Blob) result;
+        return (Blob) mergeResultSet.getValue(columnIndex, Blob.class);
     }
     
     @Override
     public Blob getBlob(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, Blob.class);
-        wasNull = null == result;
-        return (Blob) result;
+        return (Blob) mergeResultSet.getValue(columnLabel, Blob.class);
     }
     
     @Override
     public Clob getClob(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, Clob.class);
-        wasNull = null == result;
-        return (Clob) result;
+        return (Clob) mergeResultSet.getValue(columnIndex, Clob.class);
     }
         
     @Override
     public Clob getClob(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, Clob.class);
-        wasNull = null == result;
-        return (Clob) result;
+        return (Clob) mergeResultSet.getValue(columnLabel, Clob.class);
     }
     
     @Override
     public URL getURL(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, URL.class);
-        wasNull = null == result;
-        return (URL) result;
+        return (URL) mergeResultSet.getValue(columnIndex, URL.class);
     }
     
     @Override
     public URL getURL(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, URL.class);
-        wasNull = null == result;
-        return (URL) result;
+        return (URL) mergeResultSet.getValue(columnLabel, URL.class);
     }
     
     @Override
     public SQLXML getSQLXML(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, SQLXML.class);
-        wasNull = null == result;
-        return (SQLXML) result;
+        return (SQLXML) mergeResultSet.getValue(columnIndex, SQLXML.class);
     }
     
     @Override
     public SQLXML getSQLXML(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, SQLXML.class);
-        wasNull = null == result;
-        return (SQLXML) result;
+        return (SQLXML) mergeResultSet.getValue(columnLabel, SQLXML.class);
     }
     
     @Override
     public Object getObject(final int columnIndex) throws SQLException {
-        Object result = mergeResultSet.getValue(columnIndex, Object.class);
-        wasNull = null == result;
-        return result;
+        return mergeResultSet.getValue(columnIndex, Object.class);
     }
     
     @Override
     public Object getObject(final String columnLabel) throws SQLException {
-        Object result = mergeResultSet.getValue(columnLabel, Object.class);
-        wasNull = null == result;
-        return result;
+        return mergeResultSet.getValue(columnLabel, Object.class);
     }
 }
diff --git a/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/ResultSetMerger.java b/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/ResultSetMerger.java
index 537541c0ca9f9..4d62a720f7ebc 100644
--- a/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/ResultSetMerger.java
+++ b/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/ResultSetMerger.java
@@ -97,4 +97,12 @@ public interface ResultSetMerger {
      * @throws SQLException SQL Exception
      */
     InputStream getInputStream(final String columnLabel, final String type) throws SQLException;
+    
+    /**
+     * Adjust ResultSet is null or not.
+     * 
+     * @return ResultSet is null or not
+     * @throws SQLException SQL Exception
+     */
+    boolean wasNull() throws SQLException;
 }
diff --git a/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractDecoratorResultSetMerger.java b/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractDecoratorResultSetMerger.java
index b9bc105e036c1..d639c30567f2d 100644
--- a/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractDecoratorResultSetMerger.java
+++ b/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractDecoratorResultSetMerger.java
@@ -65,4 +65,9 @@ public InputStream getInputStream(final int columnIndex, final String type) thro
     public InputStream getInputStream(final String columnLabel, final String type) throws SQLException {
         return resultSetMerger.getInputStream(columnLabel, type);
     }
+    
+    @Override
+    public boolean wasNull() throws SQLException {
+        return resultSetMerger.wasNull();
+    }
 }
diff --git a/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractMemoryResultSetMerger.java b/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractMemoryResultSetMerger.java
index b3a74bc8e975a..dbe879ae31cbf 100644
--- a/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractMemoryResultSetMerger.java
+++ b/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractMemoryResultSetMerger.java
@@ -44,12 +44,16 @@ public abstract class AbstractMemoryResultSetMerger implements ResultSetMerger {
     @Setter
     private MemoryResultSetRow currentResultSetRow;
     
+    private boolean wasNull;
+    
     @Override
     public Object getValue(final int columnIndex, final Class<?> type) throws SQLException {
         if (Blob.class == type || Clob.class == type || Reader.class == type || InputStream.class == type || SQLXML.class == type) {
             throw new SQLFeatureNotSupportedException();
         }
-        return currentResultSetRow.getCell(columnIndex);
+        Object result = currentResultSetRow.getCell(columnIndex);
+        wasNull = null == result;
+        return result;
     }
     
     @Override
@@ -57,19 +61,25 @@ public Object getValue(final String columnLabel, final Class<?> type) throws SQL
         if (Blob.class == type || Clob.class == type || Reader.class == type || InputStream.class == type || SQLXML.class == type) {
             throw new SQLFeatureNotSupportedException();
         }
-        return currentResultSetRow.getCell(labelAndIndexMap.get(columnLabel));
+        Object result =  currentResultSetRow.getCell(labelAndIndexMap.get(columnLabel));
+        wasNull = null == result;
+        return result;
     }
     
     @Override
     public Object getCalendarValue(final int columnIndex, final Class<?> type, final Calendar calendar) throws SQLException {
         // TODO 时间相关取值未实现calendar模式
-        return currentResultSetRow.getCell(columnIndex);
+        Object result = currentResultSetRow.getCell(columnIndex);
+        wasNull = null == result;
+        return result;
     }
     
     @Override
     public Object getCalendarValue(final String columnLabel, final Class<?> type, final Calendar calendar) throws SQLException {
         // TODO 时间相关取值未实现calendar模式
-        return currentResultSetRow.getCell(labelAndIndexMap.get(columnLabel));
+        Object result = currentResultSetRow.getCell(labelAndIndexMap.get(columnLabel));
+        wasNull = null == result;
+        return result;
     }
     
     @Override
@@ -81,4 +91,9 @@ public InputStream getInputStream(final int columnIndex, final String type) thro
     public InputStream getInputStream(final String columnLabel, final String type) throws SQLException {
         throw new SQLFeatureNotSupportedException();
     }
+    
+    @Override
+    public boolean wasNull() throws SQLException {
+        return wasNull;
+    }
 }
diff --git a/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractStreamResultSetMerger.java b/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractStreamResultSetMerger.java
index 03562fd042920..4e46bba009336 100644
--- a/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractStreamResultSetMerger.java
+++ b/sharding-jdbc-core/src/main/java/com/dangdang/ddframe/rdb/sharding/merger/common/AbstractStreamResultSetMerger.java
@@ -44,6 +44,8 @@ public abstract class AbstractStreamResultSetMerger implements ResultSetMerger {
     
     private ResultSet currentResultSet;
     
+    private boolean wasNull;
+    
     protected ResultSet getCurrentResultSet() throws SQLException {
         if (null == currentResultSet) {
             throw new SQLException("Current ResultSet is null, ResultSet perhaps end of next.");
@@ -53,183 +55,232 @@ protected ResultSet getCurrentResultSet() throws SQLException {
     
     @Override
     public Object getValue(final int columnIndex, final Class<?> type) throws SQLException {
+        Object result;
         if (Object.class == type) {
-            return getCurrentResultSet().getObject(columnIndex);
-        }
-        if (boolean.class == type) {
-            return getCurrentResultSet().getBoolean(columnIndex);
-        }
-        if (byte.class == type) {
-            return getCurrentResultSet().getByte(columnIndex);
-        }
-        if (short.class == type) {
-            return getCurrentResultSet().getShort(columnIndex);
-        }
-        if (int.class == type) {
-            return getCurrentResultSet().getInt(columnIndex);
-        }
-        if (long.class == type) {
-            return getCurrentResultSet().getLong(columnIndex);
-        }
-        if (float.class == type) {
-            return getCurrentResultSet().getFloat(columnIndex);
-        }
-        if (double.class == type) {
-            return getCurrentResultSet().getDouble(columnIndex);
-        }
-        if (String.class == type) {
-            return getCurrentResultSet().getString(columnIndex);
-        }
-        if (BigDecimal.class == type) {
-            return getCurrentResultSet().getBigDecimal(columnIndex);
-        }
-        if (byte[].class == type) {
-            return getCurrentResultSet().getBytes(columnIndex);
-        }
-        if (Date.class == type) {
-            return getCurrentResultSet().getDate(columnIndex);
-        }
-        if (Time.class == type) {
-            return getCurrentResultSet().getTime(columnIndex);
-        }
-        if (Timestamp.class == type) {
-            return getCurrentResultSet().getTimestamp(columnIndex);
-        }
-        if (URL.class == type) {
-            return getCurrentResultSet().getURL(columnIndex);
-        }
-        if (Blob.class == type) {
-            return getCurrentResultSet().getBlob(columnIndex);
-        }
-        if (Clob.class == type) {
-            return getCurrentResultSet().getClob(columnIndex);
-        }
-        if (SQLXML.class == type) {
-            return getCurrentResultSet().getSQLXML(columnIndex);
-        }
-        if (Reader.class == type) {
-            return getCurrentResultSet().getCharacterStream(columnIndex);
-        }
-        return getCurrentResultSet().getObject(columnIndex);
+            result = getCurrentResultSet().getObject(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (boolean.class == type) {
+            result = getCurrentResultSet().getBoolean(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (byte.class == type) {
+            result = getCurrentResultSet().getByte(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (short.class == type) {
+            result = getCurrentResultSet().getShort(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (int.class == type) {
+            result = getCurrentResultSet().getInt(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (long.class == type) {
+            result = getCurrentResultSet().getLong(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (float.class == type) {
+            result = getCurrentResultSet().getFloat(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (double.class == type) {
+            result = getCurrentResultSet().getDouble(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (String.class == type) {
+            result = getCurrentResultSet().getString(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (BigDecimal.class == type) {
+            result = getCurrentResultSet().getBigDecimal(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (byte[].class == type) {
+            result = getCurrentResultSet().getBytes(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (Date.class == type) {
+            result = getCurrentResultSet().getDate(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (Time.class == type) {
+            result = getCurrentResultSet().getTime(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (Timestamp.class == type) {
+            result = getCurrentResultSet().getTimestamp(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (URL.class == type) {
+            result = getCurrentResultSet().getURL(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (Blob.class == type) {
+            result = getCurrentResultSet().getBlob(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (Clob.class == type) {
+            result = getCurrentResultSet().getClob(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (SQLXML.class == type) {
+            result = getCurrentResultSet().getSQLXML(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else if (Reader.class == type) {
+            result = getCurrentResultSet().getCharacterStream(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+            return result;
+        } else {
+            result = getCurrentResultSet().getObject(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+        }
+        return result;
     }
     
     @Override
     public Object getValue(final String columnLabel, final Class<?> type) throws SQLException {
+        Object result;
         if (Object.class == type) {
-            return getCurrentResultSet().getObject(columnLabel);
-        }
-        if (boolean.class == type) {
-            return getCurrentResultSet().getBoolean(columnLabel);
-        }
-        if (byte.class == type) {
-            return getCurrentResultSet().getByte(columnLabel);
-        }
-        if (short.class == type) {
-            return getCurrentResultSet().getShort(columnLabel);
-        }
-        if (int.class == type) {
-            return getCurrentResultSet().getInt(columnLabel);
-        }
-        if (long.class == type) {
-            return getCurrentResultSet().getLong(columnLabel);
-        }
-        if (float.class == type) {
-            return getCurrentResultSet().getFloat(columnLabel);
-        }
-        if (double.class == type) {
-            return getCurrentResultSet().getDouble(columnLabel);
-        }
-        if (String.class == type) {
-            return getCurrentResultSet().getString(columnLabel);
-        }
-        if (BigDecimal.class == type) {
-            return getCurrentResultSet().getBigDecimal(columnLabel);
-        }
-        if (byte[].class == type) {
-            return getCurrentResultSet().getBytes(columnLabel);
-        }
-        if (Date.class == type) {
-            return getCurrentResultSet().getDate(columnLabel);
-        }
-        if (Time.class == type) {
-            return getCurrentResultSet().getTime(columnLabel);
-        }
-        if (Timestamp.class == type) {
-            return getCurrentResultSet().getTimestamp(columnLabel);
-        }
-        if (URL.class == type) {
-            return getCurrentResultSet().getURL(columnLabel);
-        }
-        if (Blob.class == type) {
-            return getCurrentResultSet().getBlob(columnLabel);
-        }
-        if (Clob.class == type) {
-            return getCurrentResultSet().getClob(columnLabel);
-        }
-        if (SQLXML.class == type) {
-            return getCurrentResultSet().getSQLXML(columnLabel);
-        }
-        if (Reader.class == type) {
-            return getCurrentResultSet().getCharacterStream(columnLabel);
-        }
-        return getCurrentResultSet().getObject(columnLabel);
+            result = getCurrentResultSet().getObject(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (boolean.class == type) {
+            result = getCurrentResultSet().getBoolean(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (byte.class == type) {
+            result = getCurrentResultSet().getByte(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (short.class == type) {
+            result = getCurrentResultSet().getShort(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (int.class == type) {
+            result = getCurrentResultSet().getInt(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (long.class == type) {
+            result = getCurrentResultSet().getLong(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (float.class == type) {
+            result = getCurrentResultSet().getFloat(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (double.class == type) {
+            result = getCurrentResultSet().getDouble(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (String.class == type) {
+            result = getCurrentResultSet().getString(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (BigDecimal.class == type) {
+            result = getCurrentResultSet().getBigDecimal(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (byte[].class == type) {
+            result = getCurrentResultSet().getBytes(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (Date.class == type) {
+            result = getCurrentResultSet().getDate(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (Time.class == type) {
+            result = getCurrentResultSet().getTime(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (Timestamp.class == type) {
+            result = getCurrentResultSet().getTimestamp(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (URL.class == type) {
+            result = getCurrentResultSet().getURL(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (Blob.class == type) {
+            result = getCurrentResultSet().getBlob(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (Clob.class == type) {
+            result = getCurrentResultSet().getClob(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (SQLXML.class == type) {
+            result = getCurrentResultSet().getSQLXML(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (Reader.class == type) {
+            result = getCurrentResultSet().getCharacterStream(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else {
+            result = getCurrentResultSet().getObject(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        }
+        return result;
     }
     
     @Override
     public Object getCalendarValue(final int columnIndex, final Class<?> type, final Calendar calendar) throws SQLException {
+        Object result;
         if (Date.class == type) {
-            return getCurrentResultSet().getDate(columnIndex, calendar);
-        }
-        if (Time.class == type) {
-            return getCurrentResultSet().getTime(columnIndex, calendar);
-        }
-        if (Timestamp.class == type) {
-            return getCurrentResultSet().getTimestamp(columnIndex, calendar);
-        }
-        throw new SQLException(String.format("Unsupported type: %s", type));
+            result = getCurrentResultSet().getDate(columnIndex, calendar);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (Time.class == type) {
+            result = getCurrentResultSet().getTime(columnIndex, calendar);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (Timestamp.class == type) {
+            result = getCurrentResultSet().getTimestamp(columnIndex, calendar);
+            wasNull = getCurrentResultSet().wasNull();
+        } else {
+            throw new SQLException(String.format("Unsupported type: %s", type));
+        }
+        return result;
     }
     
     @Override
     public Object getCalendarValue(final String columnLabel, final Class<?> type, final Calendar calendar) throws SQLException {
+        Object result;
         if (Date.class == type) {
-            return getCurrentResultSet().getDate(columnLabel, calendar);
-        }
-        if (Time.class == type) {
-            return getCurrentResultSet().getTime(columnLabel, calendar);
-        }
-        if (Timestamp.class == type) {
-            return getCurrentResultSet().getTimestamp(columnLabel, calendar);
-        }
-        throw new SQLException(String.format("Unsupported type: %s", type));
+            result = getCurrentResultSet().getDate(columnLabel, calendar);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (Time.class == type) {
+            result = getCurrentResultSet().getTime(columnLabel, calendar);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if (Timestamp.class == type) {
+            result = getCurrentResultSet().getTimestamp(columnLabel, calendar);
+            wasNull = getCurrentResultSet().wasNull();
+        } else {
+            throw new SQLException(String.format("Unsupported type: %s", type));
+        }
+        return result;
     }
     
     @SuppressWarnings("deprecation")
     @Override
     public InputStream getInputStream(final int columnIndex, final String type) throws SQLException {
+        InputStream result;
         if ("Ascii".equals(type)) {
-            return getCurrentResultSet().getAsciiStream(columnIndex);
-        }
-        if ("Unicode".equals(type)) {
-            return getCurrentResultSet().getUnicodeStream(columnIndex);
-        }
-        if ("Binary".equals(type)) {
-            return getCurrentResultSet().getBinaryStream(columnIndex);
-        }
-        throw new SQLException(String.format("Unsupported type: %s", type));
+            result = getCurrentResultSet().getAsciiStream(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if ("Unicode".equals(type)) {
+            result = getCurrentResultSet().getUnicodeStream(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if ("Binary".equals(type)) {
+            result = getCurrentResultSet().getBinaryStream(columnIndex);
+            wasNull = getCurrentResultSet().wasNull();
+        } else {
+            throw new SQLException(String.format("Unsupported type: %s", type));
+        }
+        return result;
     }
     
     @SuppressWarnings("deprecation")
     @Override
     public InputStream getInputStream(final String columnLabel, final String type) throws SQLException {
+        InputStream result;
         if ("Ascii".equals(type)) {
-            return getCurrentResultSet().getAsciiStream(columnLabel);
-        }
-        if ("Unicode".equals(type)) {
-            return getCurrentResultSet().getUnicodeStream(columnLabel);
-        }
-        if ("Binary".equals(type)) {
-            return getCurrentResultSet().getBinaryStream(columnLabel);
-        }
-        throw new SQLException(String.format("Unsupported type: %s", type));
+            result = getCurrentResultSet().getAsciiStream(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if ("Unicode".equals(type)) {
+            result = getCurrentResultSet().getUnicodeStream(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else if ("Binary".equals(type)) {
+            result = getCurrentResultSet().getBinaryStream(columnLabel);
+            wasNull = getCurrentResultSet().wasNull();
+        } else {
+            throw new SQLException(String.format("Unsupported type: %s", type));
+        }
+        return result;
+    }
+    
+    @Override
+    public boolean wasNull() throws SQLException {
+        return wasNull;
     }
 }