code: static public BooleanExpression OR(Collection<? extends BooleanExpression> operands){
  		BooleanExpression result = new BooleanExpression(OPERATOR_OR);
  		result.addOperand(operands);
  		return result;
  	}
docs: 创建用OR连接的表达式
  @param operands
  @return	用OR连接之后的表达式