PHP/Java integration where PHP meets Java again¶

Introduction¶

In short soluble-japha allows to write Java code in PHP and interact with the JVM ecosystem. As meaningless examples:

<?php
// Some standard JVM classes
$hashMap = $ba->java('java.util.HashMap', [
        'message' => 'Hello world',
        'value'   => $ba->java('java.math.BigInteger', PHP_INT_MAX)
]);
$hashMap->put('message', '你好，世界');
echo $hashMap->get('message');

<?php
// An imaginary java library class (i.e. NLP, Android, Jasper, Tensorflow,
// enterprise stuff, esoteric java lib/driver or your own Java class...)
try {
    $javaLib = $ba->java('an.imaginary.JavaLibraryClass', 'param1', 'param2');

    $results = $javaLib->aMethodOnJavaLibExecutedOnTheJVM(
                            // Method parameters
                            $hashMap->get('message'),
                            $ba->java('java.io.BufferedReader',
                                 $ba->java('java.io.FileReader', __FILE__)
                            ),
                            $ba->javaClass('java.util.TimeZone')->SHORT
                        );

    foreach ($results as $key => $values) {
        echo "$key: " . $values[0] . PHP_EOL;
    }
} catch (Exception\ClassNotFoundException $e) {
    echo $e->getMessage();
} catch (Exception\JavaException $e) {
    echo $e->getMessage() . ' [' . $e->getJavaClassName() . ']';
    echo $e->getStackTrace();
}

Use cases¶

Expand the PHP horizons to the Java ecosystem whenever you want to quickly play with

some compelling libraries (Jasperreports, CoreNLP, FlyingSaucer, Jsoup...)
benefit from JVM performances (Deeplearning4J...) or wrappers (TensorFlowApi...)
when a pure-PHP alternative does not exists (Android, driver, closed api, enterprise...)
or simply for the fun of it.

Features¶

soluble-japha provides a PHP client to interact with the Java Virtual Machine.

Write Java code from PHP (in a similar way from equivalent java code).
Keep programmatic code control from the PHP side (function oriented vs REST).
Java execution on the JVM ensuring compatibility and efficiency (proxied objects).
No need to write a service layer prior to usage (the Java object is the contract).
Network based communication between runtimes (no JVM startup effort).
Solid foundation to create, develop or publish PHP wrappers over java libs.

How it works¶

sequenceDiagram Note over SolubleJapha: Serialize call SolubleJapha->>+PHPJavaBridgeServer: XML Payload Note over PHPJavaBridgeServer, JVM: Deserialize and init context PHPJavaBridgeServer->JVM: Execute <br />the call on the JVM PHPJavaBridgeServer-->>-SolubleJapha: XML Payload Note over SolubleJapha: Deserialize response

Considerations¶

Summary

In short, the bridge shines whenever you need to use directly a Java library within a reasonable number of method calls. Otherwise implement REST or RPC approaches for first-class system integrations. See the how it works and performance sections to learn more.

The soluble-japha bridge can be seen as a function oriented solution in comparison to resource oriented ones (i.e. REST,...). From REST or even RPC-based solutions (XMLRPC, JsonRPC or gRPC), the bridge skips the need to write a service layer on the Java side and allows a more programmatic approach to PHP developers.

Depending on usage, the benefits of freedom offered by the bridge can become a limitation in term of performance. Keep in mind that the bridge is sensitive to the number of objects and method calls (named roundtrips) and if few hundreds of methods calls are often insignificant (a roundtrip is generally less than 0.1ms, see benchmarks) going further its target scenarios can be disappointing. In those case, traditional approaches like REST should be considered and applied instead.

That said, the bridge is a good, reliable and sometimes preferable alternative over REST for scenarios where a reasonable number of methods calls is intended or whenever you want to keep control of the code on the PHP side.

Tip

Be sure to read the optimizations techniques while developing with the bridge.

Support¶

Please fill any issues on the offical tracker. If you like to contribute, see the contribution guidelines. All P/R are warmly welcomed.