private String contrast() {
        final PluginHandleDO before = (PluginHandleDO) getBefore();
        Objects.requireNonNull(before);
        final PluginHandleDO after = (PluginHandleDO) getAfter();
        Objects.requireNonNull(after);
        if (Objects.equals(before, after)) {
            return "it no change";
        }
        final StringBuilder builder = new StringBuilder();
        if (!Objects.equals(before.getField(), after.getField())) {
            builder.append(String.format("field[%s => %s] ", before.getField(), after.getField()));
        }
        if (!Objects.equals(before.getLabel(), after.getLabel())) {
            builder.append(String.format("label[%s => %s] ", before.getLabel(), after.getLabel()));
        }
        if (!Objects.equals(before.getType(), after.getType())) {
            builder.append(String.format("type[%s => %s] ", before.getType(), after.getType()));
        }
        if (!Objects.equals(before.getDataType(), after.getDataType())) {
            builder.append(String.format("dataType[%s => %s] ", before.getDataType(), after.getDataType()));
        }
        if (!Objects.equals(before.getSort(), after.getSort())) {
            builder.append(String.format("sort[%s => %s] ", before.getSort(), after.getSort()));
        }
        return builder.toString();
    }
Create a new {@code PluginChangedEvent}.operator is unknown.

@param source   Current plugin state
@param before   Before the change plugin state
@param type     event type
@param operator operator
shenyu-admin/src/main/java/org/apache/shenyu/admin/model/event/handle/PluginHandleChangedEvent.java