org.thales.punch.libraries.punchlang.operator

Class ToFlatTupleOperator

java.lang.Object

org.thales.punch.libraries.punchlang.operator.ToFlatTupleOperator

public class ToFlatTupleOperator
extends Object

The ToFlatTupleOperator operator transforms a Punch Tuple into another, containing only one-level flat key-values. You have several variants. Say you have the following input tuple:

 {
  "bookstore_city": "paris",
  "books_price": [
    22,
    13
  ],
  "bookstore_id": 16,
  "books_title": [
    "war and piece",
    "learning the punch"
  ]
}
 

If you simply run :

 
        Tuple flat  = toFlatTuple().on(input);
 
 

it produces a the following flat tuple:

 
 {
      "books_0_title": "war and piece",
      "bookstore_city": "paris",
      "books_1_price": "13",
      "bookstore_id": "16",
      "books_0_price": "22",
      "books_1_title": "learning the punch"
    }
 

Notice that arrays are flattened as well. In some case you want to preserve arrays. Do as follows:

 Tuple flat  = toFlatTuple().preserveArrays().on(input);
 

it produces :

    {
     "bookstore_city": "paris",
      "books_price": [
        "22",
        "13"
      ],
      "bookstore_id": "16",
      "books_title": [
        "war and piece",
        "learning the punch"
      ]
    }
 

In the two last examples all the values were converted as strings. If you want to preserve the original types, use the preserveTypes() method. Tuple flat = toFlatTuple().preserveTypes().on(input);

Constructor Summary

Constructors

Constructor and Description
ToFlatTupleOperator() Create a new ToFlatTupleOperator operator.

Method Summary

Modifier and Type	Method and Description
ToFlatTupleOperator	nestedSeparator(String separator) Set the string to be used to separate nested properties when creating the tuple keys.
Tuple	on(Tuple input) Make the operator work on an input Tuple.
ToFlatTupleOperator	preserveArrays() Preserve the arrays.
ToFlatTupleOperator	preserveTypes()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

ToFlatTupleOperator

public ToFlatTupleOperator()

Create a new ToFlatTupleOperator operator.

Method Detail

on

public Tuple on(Tuple input)

Make the operator work on an input Tuple. The Tuple must contain a String leaf value.

Parameters:

input - the input Tuple

Returns:

this operator

preserveTypes

public ToFlatTupleOperator preserveTypes()

nestedSeparator

public ToFlatTupleOperator nestedSeparator(String separator)

Set the string to be used to separate nested properties when creating the tuple keys. By default a "." is used.

Parameters:

separator - the separator you want.

Returns:

this operator

preserveArrays

public ToFlatTupleOperator preserveArrays()

Preserve the arrays.

Returns:

this operator.