// Copyright (c) 2009 The Chromium Authors. All rights reserved.

// Use of this source code is governed by a BSD-style license that can be

// found in the LICENSE file.

package org.chromium.sdk.internal.protocolparser;

import java.lang.annotation.ElementType;

import java.lang.annotation.Retention;

import java.lang.annotation.RetentionPolicy;

import java.lang.annotation.Target;

/**

 * Specifies a condition for a field-reading method. It is one from group of annotations

 * that mark key fields for choosing particular subtype. They set conditions on JSON fields in

 * a subtype interface that drive subtype auto-selection at parsing time.

 * <p>

 * Specifies a general condition; it requires that:

 * <ul>

 * <li>field should be null, if {@link #valueIsNull()} is true,

 * <li>field should be absent, if {@link #fieldIsAbsent()} is true,

 * <li>field should exist, if no options are set.

 * </ul>

 */

@Target({ElementType.METHOD})

@Retention(RetentionPolicy.RUNTIME)

public @interface JsonSubtypeCondition {

  boolean fieldIsAbsent() default false;

  boolean valueIsNull() default false;

}