Bug 156166 Error occour when previewing attached report in web viewer.
Decription:Error occour when previewing attached report in web viewer. Steps to reproduce: 1.run attached reports in web viewer. Expeceted results: preview properly Actual results: Error occour when previewing the reports in web viewer while it works properly in html and PDF
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/impl/document/util/ExprDataReader2.java
for ( int i = 0; i < exprCount; i++ )
		{
			String exprID = this.exprKeys.get( i ).toString( );
			Object exprValue = IOUtil.readObject( rowExprsDis );
			valueMap.put( exprID, exprValue );
		}
		return valueMap;
	}
	
	/*
	 * @see org.eclipse.birt.data.engine.impl.document.IExprResultReader#close()
	 */
	public void close( )
	{
		try
		{			
			if ( rowExprsDis != null )
			{
				rowExprsDis.close( );
				rowExprsDis = null;
			}
		}
		catch ( IOException e )
		{
			
		}
	}
	
}