package io.vertx.core.json.pointer;

import io.vertx.codegen.annotations.Nullable;
import io.vertx.codegen.annotations.VertxGen;
import io.vertx.core.json.pointer.impl.JsonPointerIteratorImpl;

The JsonPointerIterator is used by the read/write algorithms of the JsonPointer to read/write the querying data structure 

Every method takes the currentValue as parameter, representing the actual value held by the query algorithm.

Implementations of this interface should be stateless, so they can be reused

You can implement this interface to query the structure you want using json pointers
Author:
Francesco Guardiani @slinkydeveloper/**
 * The JsonPointerIterator is used by the read/write algorithms of the {@link JsonPointer} to read/write the querying data structure <br/>
 *
 * Every method takes the currentValue as parameter, representing the actual value held by the query algorithm.<br/>
 *
 * Implementations of this interface should be stateless, so they can be reused<br/>
 *
 * You can implement this interface to query the structure you want using json pointers
 *
 * @author Francesco Guardiani <a href="https://slinkydeveloper.github.io/">@slinkydeveloper</a>
 *
 */
@VertxGen
public interface JsonPointerIterator {

  
Params:
currentValue – 
Returns:
true if the current value is a queryable object/**
   * @param currentValue
   * @return {@code true} if the current value is a queryable object
   */
  boolean isObject(@Nullable Object currentValue);

  
Params:
currentValue – 
Returns:
true if the current value is a queryable array/**
   * @param currentValue
   * @return {@code true} if the current value is a queryable array
   */
  boolean isArray(@Nullable Object currentValue);

  
Params:
currentValue – 
Returns:
true if the current value is null/empty/**
   * @param currentValue
   * @return {@code true} if the current value is null/empty
   */
  boolean isNull(@Nullable Object currentValue);

  
Params:
currentValue – 
key – object key
Returns:
true if current value is a queryable object that contains the specified key/**
   * @param currentValue
   * @param key object key
   * @return {@code true} if current value is a queryable object that contains the specified key
   */
  boolean objectContainsKey(@Nullable Object currentValue, String key);

  
Returns the object parameter with specified key.
Params:
currentValue – 
key – object key
createOnMissing – If the current value is an object that doesn't contain the key, put an empty object at provided key
Returns:
the requested object parameter, or null if the method was not able to find it/**
   * Returns the object parameter with specified key.
   *
   * @param currentValue
   * @param key object key
   * @param createOnMissing If the current value is an object that doesn't contain the key, put an empty object at provided key
   * @return the requested object parameter, or null if the method was not able to find it
   */
  Object getObjectParameter(@Nullable Object currentValue, String key, boolean createOnMissing);

  
Move the iterator the the array element at specified index
Params:
currentValue – 
i – array index
Returns:
the request array element, or null if the method was not able to find it/**
   * Move the iterator the the array element at specified index
   *
   * @param currentValue
   * @param i array index
   * @return the request array element, or null if the method was not able to find it
   */
  Object getArrayElement(@Nullable Object currentValue, int i);

  
Write object parameter at specified key
Params:
currentValue – 
key – 
value – 
Returns:
true if the operation is successful/**
   * Write object parameter at specified key
   *
   * @param currentValue
   * @param key
   * @param value
   * @return true if the operation is successful
   */
  boolean writeObjectParameter(@Nullable Object currentValue, String key, @Nullable Object value);

  
Write array element at specified index
Params:
currentValue – 
i – 
value – 
Returns:
true if the operation is successful/**
   * Write array element at specified index
   *
   * @param currentValue
   * @param i
   * @param value
   * @return true if the operation is successful
   */
  boolean writeArrayElement(@Nullable Object currentValue, int i, @Nullable Object value);

  
Append array element
Params:
currentValue – 
value – 
Returns:
true if the operation is successful/**
   * Append array element
   *
   * @param currentValue
   * @param value
   * @return true if the operation is successful
   */
  boolean appendArrayElement(@Nullable Object currentValue, @Nullable Object value);

  
Instance of a JsonPointerIterator to query Vert.x Json structures
/**
   * Instance of a JsonPointerIterator to query Vert.x Json structures
   */
  JsonPointerIterator JSON_ITERATOR = new JsonPointerIteratorImpl();

}