Bug 206861 The data set cache should handle IOException and the cancel request from customer
The data set data will be saved into disk file in the first query and it will be loaded in the later time. The processing of write disk file may be cancelled by customer request or IOException. Using the data from the bad file will cause error.
data/org.eclipse.birt.data.tests/test/org/eclipse/birt/data/engine/binding/DataSetCacheTest.java
}
				for ( int j = groupCount; j < beArray.length; j++ )
				{
					String value = ri.getValue( beArray[j] ).toString( );
					rowData += formatStr( value, expectedLen );
				}
			}
			sBuffer.append( rowData );
			sBuffer.append( "\n" );
		}
		return new String( sBuffer );
	}
	/**
	 * Format string to specified length, if the length of input string is
	 * larger than expected length, then input string will be directly return
	 * without any format.
	 * 
	 * @param str
	 *            needs to be formatted string
	 * @param length
	 *            expected length
	 * @return formatted string
	 */
	private static String formatStr( String inputStr, int length )
	{
		if ( inputStr == null )
			return null;
		int inputLen = inputStr.length( );
		if ( inputLen >= length )
			return inputStr;