Bug 201030 NPE throws out when preview the attached report design
data/org.eclipse.birt.data/src/org/eclipse/birt/data/engine/script/ScriptEvalUtil.java
private static boolean like( Object source, Object pattern ) throws DataException
	{
		String sourceStr = (source == null)? "": source.toString();
		String patternStr = ( pattern == null )? "" : pattern.toString();
	
		
		
		
		 
		
		
		
		final String reservedChars = "([{^$|)?*+.";
		int patternLen = patternStr.length();
		StringBuffer buffer = new StringBuffer( patternLen * 2 );
		
		for ( int i = 0; i < patternLen; i++)
		{
			char c = patternStr.charAt(i);
			if ( c == '\\' )
			{
				 
				
				++i;
				if ( i < patternLen )
				{
					c = patternStr.charAt( i );
					if ( c == '%' || c == '_' )
						buffer.append( c );
					else if ( c == '\\' )