code: public static <T> String getCustomDeleteSQL(T t, List<Object> values, String setSql) {
  		StringBuilder sql = new StringBuilder();
  		sql.append("UPDATE ");
  
  		Table table = DOInfoReader.getTable(t.getClass());
  		List<Field> fields = DOInfoReader.getColumns(t.getClass());
  		List<Field> keyFields = DOInfoReader.getKeyColumns(t.getClass());
  
  		sql.append(getTableName(table)).append(" ");
  
  		if(setSql.trim().toLowerCase().startsWith("set ")) {
  			sql.append(setSql);
  		} else {
  			sql.append("SET ").append(setSql);
  		}
  
  		// 加上删除时间
  		for(Field field : fields) {
  			Column column = field.getAnnotation(Column.class);
  			if(column.setTimeWhenDelete() && Date.class.isAssignableFrom(field.getType())) {
  				sql.append(",").append(getColumnName(column))
  						.append("=").append(getDateString(new Date()));
  			}
  		}
  
  		List<Object> whereValues = new ArrayList<Object>();
  		String where = "WHERE " + joinWhereAndGetValue(keyFields, "AND", whereValues, t);
  
  		for(Object value : whereValues) {
  			if(value == null) {
  				throw new NullKeyValueException();
  			}
  		}
  		values.addAll(whereValues);
  
  		sql.append(autoSetSoftDeleted(where, t.getClass()));
  
  		return sql.toString();
  	}
docs: 获得自定义更新的sql
  @param t
  @param values
  @param setSql
  @return