Optimization techniques

Note

Be sure to have read the how it works and benchmark pages to understand the reasons behind the proposed optimization techniques.

Values method

Iterating over Java arrays (HashMap, ArrayList, Vector...) to retrieves their values in a PHP loop (while, foreach...) produce a lot of roundtrips with the bridge that can lead to poor performance.

Instead, you can use the values() method to retrieve the values in one run:

HashMap example

<?php
$arrOfArray = [
    'real' => true,
    'what' => 'Too early to know',
    'count' => 2017,
    'arr10000' => array_fill(0, 10000, 'Hello world')

];

$hashMap = $ba->java('java.util.HashMap', $arrOfArray);
$arrFromJava = $ba->values($hashMap);

// $arrOfArray is identical from $arrFromJava (one roundtrip) 

Vector example

<?php

$array = array_fill(0, 1000, 'Hello');
$vector = $ba->java('java.util.Vector', $array);

$values = $ba->values($vector);
// $values === $array 

Optimizing loops

One of many techniques to solve loop/iterations issues (increase rountrips) is to build an ArrayList, Linked list on the Java side instead of iterating from the PHP side.

WIP: see the JDBCPerformanceTest.

Java serialization

Whenever you need to retrieve a complex object structure (deep nesting...), you can use object serialization on the backend. See the recipes for json serialization as an example.