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<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<head>

<title>FlatBuffers: Tutorial</title>

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<div id="projectname">FlatBuffers

</div>

An open source project by <a href="https://developers.google.com/games/#Tools">FPL</a>.

</div>

</td>

</tr>

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</table>

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<li><a href="usergroup0.html"><span>Programmer's Guide</span></a></li>

<li><a href="flatbuffers_support.html"><span>Platform / Language / Feature support</span></a></li>

<li><a href="flatbuffers_benchmarks.html"><span>Benchmarks</span></a></li>

<li><a href="flatbuffers_white_paper.html"><span>FlatBuffers white paper</span></a></li>

<li><a href="flatbuffers_internals.html"><span>FlatBuffers internals</span></a></li>

<li><a href="flatbuffers_grammar.html"><span>Grammar of the schema langauge</span></a></li>

<li><a href="usergroup1.html"><span>API Reference</span></a></li>

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<div class="title">Tutorial </div> </div>

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<div class="textblock"><h2>Overview</h2>

<p>This tutorial provides a basic example of how to work with <a class="el" href="index.html#flatbuffers_overview">FlatBuffers</a>. We will step through a simple example application, which shows you how to:</p>

<ul>

<li>Write a FlatBuffer <code>schema</code> file.</li>

<li>Use the <code>flatc</code> FlatBuffer compiler.</li>

<li>Parse <a href="http://json.org">JSON</a> files that conform to a schema into FlatBuffer binary files.</li>

<li>Use the generated files in many of the supported languages (such as C++, Java, and more.)</li>

</ul>

<p>During this example, imagine that you are creating a game where the main character, the hero of the story, needs to slay some <code>orc</code>s. We will walk through each step necessary to create this monster type using FlatBuffers.</p>

<p>Please select your desired language for our quest:</p>

<p>

<form>

<input type="radio" name="language" value="python">Python</input>

<input type="radio" name="language" value="javascript">JavaScript</input>

</form>

</p>

<p>

/**

* Check if an HTML `class` attribute is in the language-specific format.

* @param {string} languageClass An HTML `class` attribute in the format

* 'language-{lang}', where {lang} is a programming language (e.g. 'cpp',

* 'java', 'go', etc.).

* @return {boolean} Returns `true` if `languageClass` was in the valid

* format, prefixed with 'language-'. Otherwise, it returns false.

function isProgrammingLanguageClassName(languageClass) {

if (languageClass && languageClass.substring(0, 9) == 'language-' &&

languageClass.length > 8) {

return true;

} else {

return false;

}

/**

* Given a language-specific HTML `class` attribute, extract the language.

* @param {string} languageClass The string name of an HTML `class` attribute,

* in the format `language-{lang}`, where {lang} is a programming language

* (e.g. 'cpp', 'java', 'go', etc.).

* @return {string} Returns a string containing only the {lang} portion of

* the class name. If the input was invalid, then it returns `null`.

function extractProgrammingLanguageFromLanguageClass(languageClass) {

if (isProgrammingLanguageClassName(languageClass)) {

return languageClass.substring(9);

} else {

return null;

}

/**

* Hide every code snippet, except for the language that is selected.

function displayChosenLanguage() {

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for (var i = 0; i < htmlElements.length; i++) {

if (isProgrammingLanguageClassName(htmlElements[i].className)) {

if (extractProgrammingLanguageFromLanguageClass(

htmlElements[i].className).toLowerCase() != selection) {

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} else {

htmlElements[i].style.display = 'initial';

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</p>

<h2>Where to Find the Example Code</h2>

<p>Samples demonstating the concepts in this example are located in the source code package, under the <code>samples</code> directory. You can browse the samples on GitHub <a href="https://github.com/google/flatbuffers/tree/master/samples">here</a>.</p>

<p>For your chosen language, please cross-reference with:</p>

<div class="language-cpp"> <a href="https://github.com/google/flatbuffers/blob/master/samples/sample_binary.cpp">sample_binary.cpp</a> </div> <div class="language-java"> <a href="https://github.com/google/flatbuffers/blob/master/samples/SampleBinary.java">SampleBinary.java</a> </div> <div class="language-csharp"> <a href="https://github.com/google/flatbuffers/blob/master/samples/SampleBinary.cs">SampleBinary.cs</a> </div> <div class="language-go"> <a href="https://github.com/google/flatbuffers/blob/master/samples/sample_binary.go">sample_binary.go</a> </div> <div class="language-python"> <a href="https://github.com/google/flatbuffers/blob/master/samples/sample_binary.py">sample_binary.py</a> </div> <div class="language-javascript"> <a href="https://github.com/google/flatbuffers/blob/master/samples/samplebinary.js">samplebinary.js</a> </div> <div class="language-php"> <a href="https://github.com/google/flatbuffers/blob/master/samples/SampleBinary.php">SampleBinary.php</a> </div><h2>Writing the Monsters' FlatBuffer Schema</h2>

<p>To start working with FlatBuffers, you first need to create a <code>schema</code> file, which defines the format for each data structure you wish to serialize. Here is the <code>schema</code> that defines the template for our monsters:</p>

<div class="fragment"><div class="line"><span class="comment">// Example IDL file for our monster's schema.</span></div>

<div class="line"><span class="keyword">namespace </span>MyGame.Sample;</div>

<div class="line"><span class="keyword">enum</span> Color:byte { Red = 0, Green, Blue = 2 }</div>

<div class="line"><span class="keyword">union </span>Equipment { Weapon } <span class="comment">// Optionally add more tables.</span></div>

<div class="line"><span class="keyword">struct </span>Vec3 {</div>

<div class="line"> x:float;</div>

<div class="line"> y:float;</div>

<div class="line"> z:float;</div>

<div class="line">table Monster {</div>

<div class="line"> pos:Vec3; <span class="comment">// Struct.</span></div>

<div class="line"> mana:<span class="keywordtype">short</span> = 150;</div>

<div class="line"> hp:<span class="keywordtype">short</span> = 100;</div>

<div class="line"> name:string;</div>

<div class="line"> friendly:<span class="keywordtype">bool</span> = <span class="keyword">false</span> (deprecated);</div>

<div class="line"> inventory:[ubyte]; <span class="comment">// Vector of scalars.</span></div>

<div class="line"> color:Color = Blue; <span class="comment">// Enum.</span></div>

<div class="line"> weapons:[Weapon]; <span class="comment">// Vector of tables.</span></div>

<div class="line"> equipped:Equipment; <span class="comment">// Union.</span></div>

<div class="line">table Weapon {</div>

<div class="line"> name:string;</div>

<div class="line"> damage:short;</div>

<div class="line">root_type Monster;</div>

</div><p>As you can see, the syntax for the <code>schema</code> <a href="https://en.wikipedia.org/wiki/Interface_description_language">Interface Definition Language (IDL)</a> is similar to those of the C family of languages, and other IDL languages. Let's examine each part of this <code>schema</code> to determine what it does.</p>

<p>The <code>schema</code> starts with a <code>namespace</code> declaration. This determines the corresponding package/namespace for the generated code. In our example, we have the <code>Sample</code> namespace inside of the <code>MyGame</code> namespace.</p>

<p>Next, we have an <code>enum</code> definition. In this example, we have an <code>enum</code> of type <code>byte</code>, named <code>Color</code>. We have three values in this <code>enum</code>: <code>Red</code>, <code>Green</code>, and <code>Blue</code>. We specify <code>Red = 0</code> and <code>Blue = 2</code>, but we do not specify an explicit value for <code>Green</code>. Since the behavior of an <code>enum</code> is to increment if unspecified, <code>Green</code> will receive the implicit value of <code>1</code>.</p>

<p>Following the <code>enum</code> is a <code>union</code>. The <code>union</code> in this example is not very useful, as it only contains the one <code>table</code> (named <code>Weapon</code>). If we had created multiple tables that we would want the <code>union</code> to be able to reference, we could add more elements to the <code>union Equipment</code>.</p>

<p>After the <code>union</code> comes a <code>struct Vec3</code>, which represents a floating point vector with <code>3</code> dimensions. We use a <code>struct</code> here, over a <code>table</code>, because <code>struct</code>s are ideal for data structures that will not change, since they use less memory and have faster lookup.</p>

<p>The <code>Monster</code> table is the main object in our FlatBuffer. This will be used as the template to store our <code>orc</code> monster. We specify some default values for fields, such as <code>mana:short = 150</code>. All unspecified fields will default to <code>0</code> or <code>NULL</code>. Another thing to note is the line <code>friendly:bool = false (deprecated);</code>. Since you cannot delete fields from a <code>table</code> (to support backwards compatability), you can set fields as <code>deprecated</code>, which will prevent the generation of accessors for this field in the generated code. Be careful when using <code>deprecated</code>, however, as it may break legacy code that used this accessor.</p>

<p>The <code>Weapon</code> table is a sub-table used within our FlatBuffer. It is used twice: once within the <code>Monster</code> table and once within the <code>Equipment</code> enum. For our <code>Monster</code>, it is used to populate a <code>vector of tables</code> via the <code>weapons</code> field within our <code>Monster</code>. It is also the only table referenced by the <code>Equipment</code> enum.</p>

<p>The last part of the <code>schema</code> is the <code>root_type</code>. The root type declares what will be the root table for the serialized data. In our case, the root type is our <code>Monster</code> table.</p>

<h4>More Information About Schemas</h4>

<p>You can find a complete guide to writing <code>schema</code> files in the <a class="el" href="flatbuffers_guide_writing_schema.html">Writing a schema</a> section of the Programmer's Guide. You can also view the formal <a class="el" href="flatbuffers_grammar.html">Grammar of the schema language</a>.</p>

<h2>Compiling the Monsters' Schema</h2>

<p>After you have written the FlatBuffers schema, the next step is to compile it.</p>

<p>If you have not already done so, please follow <a class="el" href="flatbuffers_guide_building.html">these instructions</a> to build <code>flatc</code>, the FlatBuffer compiler.</p>

<p>Once <code>flatc</code> is built successfully, compile the schema for your language:</p>

<div class="language-cpp"> <div class="fragment"><div class="line">cd flatbuffers/sample</div>

<div class="line">./../flatc --cpp samples/monster.fbs</div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line">cd flatbuffers/sample</div>

<div class="line">./../flatc --java samples/monster.fbs</div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line">cd flatbuffers/sample</div>

<div class="line">./../flatc --csharp samples/monster.fbs</div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line">cd flatbuffers/sample</div>

<div class="line">./../flatc --go samples/monster.fbs</div>

</div> </div> <div class="language-python"> <div class="fragment"><div class="line">cd flatbuffers/sample</div>

<div class="line">./../flatc --python samples/monster.fbs</div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line">cd flatbuffers/sample</div>

<div class="line">./../flatc --javascript samples/monster.fbs</div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line">cd flatbuffers/sample</div>

<div class="line">./../flatc --php samples/monster.fbs</div>

</div> </div><p>For a more complete guide to using the <code>flatc</code> compiler, pleaes read the <a class="el" href="flatbuffers_guide_using_schema_compiler.html">Using the schema compiler</a> section of the Programmer's Guide.</p>

<h2>Reading and Writing Monster FlatBuffers</h2>

<p>Now that we have compiled the schema for our programming language, we can start creating some monsters and serializing/deserializing them from FlatBuffers.</p>

<h4>Creating and Writing Orc FlatBuffers</h4>

<p>The first step is to import/include the library, generated files, etc.</p>

<div class="language-cpp"> <div class="fragment"><div class="line"><span class="preprocessor">#include "monster_generate.h"</span> <span class="comment">// This was generated by `flatc`.</span></div>

<div class="line"><span class="keyword">using namespace </span>MyGame::Sample; <span class="comment">// Specified in the schema.</span></div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line"><span class="keyword">import</span> MyGame.Sample.*; <span class="comment">//The `flatc` generated files. (Monster, Vec3, etc.)</span></div>

<div class="line"><span class="keyword">import</span> <a class="code" href="classcom_1_1google_1_1flatbuffers_1_1_flat_buffer_builder.html">com.google.flatbuffers.FlatBufferBuilder</a>;</div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line"><span class="keyword">using</span> FlatBuffers;</div>

<div class="line"><span class="keyword">using</span> MyGame.Sample; <span class="comment">// The `flatc` generated files. (Monster, Vec3, etc.)</span></div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line"><span class="keyword">import</span> (</div>

<div class="line"> flatbuffers <span class="stringliteral">"github.com/google/flatbuffers/go"</span></div>

<div class="line"> sample <span class="stringliteral">"MyGame/Sample"</span></div>

</div> </div> <div class="language-python"> <div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> <span class="keyword">import</span> flatbuffers</div>

<div class="line"><a name="l00003"></a><span class="lineno"> 3</span> <span class="comment"># Generated by `flatc`.</span></div>

<div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="keyword">import</span> MyGame.Sample.Color</div>

<div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="keyword">import</span> MyGame.Sample.Equipment</div>

<div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="keyword">import</span> MyGame.Sample.Monster</div>

<div class="line"><a name="l00007"></a><span class="lineno"> 7</span> <span class="keyword">import</span> MyGame.Sample.Vec3</div>

<div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="keyword">import</span> MyGame.Sample.Weapon</div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line"><span class="comment">// The following code is for JavaScript module loaders (e.g. Node.js). See</span></div>

<div class="line"><span class="comment">// below for a browser-based HTML/JavaScript example of including the library.</span></div>

<div class="line">var flatbuffers = require(<span class="stringliteral">'/js/flatbuffers'</span>).flatbuffers;</div>

<div class="line">var MyGame = require(<span class="stringliteral">'./monster_generated'</span>).MyGame; <span class="comment">// Generated by `flatc`.</span></div>

<div class="line"><span class="comment">// The following code is for browser-based HTML/JavaScript. Use the above code</span></div>

<div class="line"><span class="comment">// for JavaScript module loaders (e.g. Node.js).</span></div>

<div class="line"><script src=<span class="stringliteral">"../js/flatbuffers.js"</span>></script></div>

<div class="line"><script src=<span class="stringliteral">"monster_generated.js"</span>></script> <span class="comment">// Generated by `flatc`.</span></div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line"><span class="comment">// It is recommended that your use PSR autoload when using FlatBuffers in PHP.</span></div>

<div class="line"><span class="comment">// Here is an example from `SampleBinary.php`:</span></div>

<div class="line"><span class="keyword">function</span> __autoload($class_name) {</div>

<div class="line"> <span class="comment">// The last segment of the class name matches the file name.</span></div>

<div class="line"> $class = substr($class_name, strrpos($class_name, <span class="stringliteral">"\\"</span>) + 1);</div>

<div class="line"> $root_dir = join(DIRECTORY_SEPARATOR, array(dirname(dirname(__FILE__)))); <span class="comment">// `flatbuffers` root.</span></div>

<div class="line"> <span class="comment">// Contains the `*.php` files for the FlatBuffers library and the `flatc` generated files.</span></div>

<div class="line"> $paths = array(join(DIRECTORY_SEPARATOR, array($root_dir, <span class="stringliteral">"php"</span>)),</div>

<div class="line"> join(DIRECTORY_SEPARATOR, array($root_dir, <span class="stringliteral">"samples"</span>, <span class="stringliteral">"MyGame"</span>, <span class="stringliteral">"Sample"</span>)));</div>

<div class="line"> <span class="keywordflow">foreach</span> ($paths as $path) {</div>

<div class="line"> $file = join(DIRECTORY_SEPARATOR, array($path, $class . <span class="stringliteral">".php"</span>));</div>

<div class="line"> <span class="keywordflow">if</span> (file_exists($file)) {</div>

<div class="line"> require($file);</div>

<div class="line"> <span class="keywordflow">break</span>;</div>

</div> </div><p>Now we are ready to start building some buffers. In order to start, we need to create an instance of the <code>FlatBufferBuilder</code>, which will contain the buffer as it grows:</p>

<div class="language-cpp"> <div class="fragment"><div class="line"><span class="comment">// Create a `FlatBufferBuilder`, which will be used to create our</span></div>

<div class="line"><span class="comment">// monsters' FlatBuffers.</span></div>

<div class="line"><a class="code" href="classflatbuffers_1_1_flat_buffer_builder.html">flatbuffers::FlatBufferBuilder</a> builder;</div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line"><span class="comment">// Create a `FlatBufferBuilder`, which will be used to create our</span></div>

<div class="line"><span class="comment">// monsters' FlatBuffers.</span></div>

<div class="line">FlatBufferBuilder builder = <span class="keyword">new</span> FlatBufferBuilder(0);</div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line"><span class="comment">// Create a `FlatBufferBuilder`, which will be used to create our</span></div>

<div class="line"><span class="comment">// monsters' FlatBuffers.</span></div>

<div class="line">var builder = <span class="keyword">new</span> FlatBufferBuilder(1);</div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line"><span class="comment">// Create a `FlatBufferBuilder`, which will be used to create our</span></div>

<div class="line"><span class="comment">// monsters' FlatBuffers.</span></div>

<div class="line">builder := flatbuffers.NewBuilder(0)</div>

<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment"># monsters' FlatBuffers.</span></div>

<div class="line"><a name="l00003"></a><span class="lineno"> 3</span> builder = flatbuffers.Builder(0)</div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line"><span class="comment">// Create a `flatbuffer.Builder`, which will be used to create our</span></div>

<div class="line"><span class="comment">// monsters' FlatBuffers.</span></div>

<div class="line">var builder = <span class="keyword">new</span> flatbuffers.Builder(1);</div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line"><span class="comment">// Create a `FlatBufferBuilder`, which will be used to create our</span></div>

<div class="line"><span class="comment">// monsters' FlatBuffers.</span></div>

<div class="line">$builder = <span class="keyword">new</span> <a class="code" href="class_google_1_1_flat_buffers_1_1_flatbuffer_builder.html">Google\FlatBuffers\FlatbufferBuilder</a>(0);</div>

</div> </div><p>After creating the <code>builder</code>, we can start serializing our data. Before we make our <code>orc</code> Monster, lets create some <code>Weapon</code>s: a <code>Sword</code> and an <code>Axe</code>.</p>

<div class="language-cpp"> <div class="fragment"><div class="line"><span class="keyword">auto</span> weapon_one_name = builder.CreateString(<span class="stringliteral">"Sword"</span>);</div>

<div class="line"><span class="keywordtype">short</span> weapon_one_damage = 3;</div>

<div class="line"><span class="keyword">auto</span> weapon_two_name = builder.CreateString(<span class="stringliteral">"Axe"</span>);</div>

<div class="line"><span class="keywordtype">short</span> weapon_two_damage = 5;</div>

<div class="line"><span class="comment">// Use the `CreateWeapon` shortcut to create Weapons with all the fields set.</span></div>

<div class="line"><span class="keyword">auto</span> sword = CreateWeapon(builder, weapon_one_name, weapon_one_damage);</div>

<div class="line"><span class="keyword">auto</span> axe = CreateWeapon(builder, weapon_two_name, weapon_two_damage);</div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line">String weaponOneName = builder.createString(<span class="stringliteral">"Sword"</span>)</div>

<div class="line"><span class="keywordtype">short</span> weaponOneDamage = 3;</div>

<div class="line">String weaponTwoName = builder.createString(<span class="stringliteral">"Axe"</span>);</div>

<div class="line"><span class="keywordtype">short</span> weaponTwoDamage = 5;</div>

<div class="line"><span class="comment">// Use the `createWeapon()` helper function to create the weapons, since we set every field.</span></div>

<div class="line"><span class="keywordtype">int</span> sword = Weapon.createWeapon(builder, weaponOneName, weaponOneDamage);</div>

<div class="line"><span class="keywordtype">int</span> axe = Weapon.createWeapon(builder, weaponTwoName, weaponTwoDamage);</div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line">var weaponOneName = builder.CreateString(<span class="stringliteral">"Sword"</span>);</div>

<div class="line">var weaponOneDamage = 3;</div>

<div class="line">var weaponTwoName = builder.CreateString(<span class="stringliteral">"Axe"</span>);</div>

<div class="line">var weaponTwoDamage = 5;</div>

<div class="line"><span class="comment">// Use the `CreateWeapon()` helper function to create the weapons, since we set every field.</span></div>

<div class="line">var sword = Weapon.CreateWeapon(builder, weaponOneName, (short)weaponOneDamage);</div>

<div class="line">var axe = Weapon.CreateWeapon(builder, weaponTwoName, (short)weaponTwoDamage);</div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line">weaponOne := builder.CreateString(<span class="stringliteral">"Sword"</span>)</div>

<div class="line">weaponTwo := builder.CreateString(<span class="stringliteral">"Axe"</span>)</div>

<div class="line"><span class="comment">// Create the first `Weapon` ("Sword").</span></div>

<div class="line">sample.WeaponStart(builder)</div>

<div class="line">sample.Weapon.AddName(builder, weaponOne)</div>

<div class="line">sample.Weapon.AddDamage(builder, 3)</div>

<div class="line">sword := sample.WeaponEnd(builder)</div>

<div class="line"><span class="comment">// Create the second `Weapon` ("Axe").</span></div>

<div class="line">sample.WeaponStart(builder)</div>

<div class="line">sample.Weapon.AddName(builder, weaponTwo)</div>

<div class="line">sample.Weapon.AddDamage(builder, 5)</div>

<div class="line">axe := sample.WeaponEnd(builder)</div>

</div> </div> <div class="language-python"> <div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> weapon_one = builder.CreateString(<span class="stringliteral">'Sword'</span>)</div>

<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> weapon_two = builder.CreateString(<span class="stringliteral">'Axe'</span>)</div>

<div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment"># Create the first `Weapon` ('Sword').</span></div>

<div class="line"><a name="l00005"></a><span class="lineno"> 5</span> MyGame.Sample.Weapon.WeaponStart(builder)</div>

<div class="line"><a name="l00006"></a><span class="lineno"> 6</span> MyGame.Sample.Weapon.WeaponAddName(builder, weapon_one)</div>

<div class="line"><a name="l00007"></a><span class="lineno"> 7</span> MyGame.Sample.Weapon.WeaponAddDamage(builder, 3)</div>

<div class="line"><a name="l00008"></a><span class="lineno"> 8</span> sword = MyGame.Sample.Weapon.WeaponEnd(builder)</div>

<div class="line"><a name="l00010"></a><span class="lineno"> 10</span> <span class="comment"># Create the second `Weapon` ('Axe').</span></div>

<div class="line"><a name="l00011"></a><span class="lineno"> 11</span> MyGame.Sample.Weapon.WeaponStart(builder)</div>

<div class="line"><a name="l00012"></a><span class="lineno"> 12</span> MyGame.Sample.Weapon.WeaponAddName(builder, weapon_two)</div>

<div class="line"><a name="l00013"></a><span class="lineno"> 13</span> MyGame.Sample.Weapon.WeaponAddDamage(builder, 5)</div>

<div class="line"><a name="l00014"></a><span class="lineno"> 14</span> axe = MyGame.Sample.Weapon.WeaponEnd(builder)</div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line">var weaponOne = builder.createString(<span class="stringliteral">'Sword'</span>);</div>

<div class="line">var weaponTwo = builder.createString(<span class="stringliteral">'Axe'</span>);</div>

<div class="line"><span class="comment">// Create the first `Weapon` ('Sword').</span></div>

<div class="line">MyGame.Sample.Weapon.startWeapon(builder);</div>

<div class="line">MyGame.Sample.Weapon.addName(builder, weaponOne);</div>

<div class="line">MyGame.Sample.Weapon.addDamage(builder, 3);</div>

<div class="line">var sword = MyGame.Sample.Weapon.endWeapon(builder);</div>

<div class="line"><span class="comment">// Create the second `Weapon` ('Axe').</span></div>

<div class="line">MyGame.Sample.Weapon.startWeapon(builder);</div>

<div class="line">MyGame.Sample.Weapon.addName(builder, weaponTwo);</div>

<div class="line">MyGame.Sample.Weapon.addDamage(builder, 5);</div>

<div class="line">var axe = MyGame.Sample.Weapon.endWeapon(builder);</div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line"><span class="comment">// Create the `Weapon`s using the `createWeapon()` helper function.</span></div>

<div class="line">$weapon_one_name = $builder->createString(<span class="stringliteral">"Sword"</span>);</div>

<div class="line">$sword = \MyGame\Sample\Weapon::CreateWeapon($builder, $weapon_one_name, 3);</div>

<div class="line">$weapon_two_name = $builder->createString(<span class="stringliteral">"Axe"</span>);</div>

<div class="line">$axe = \MyGame\Sample\Weapon::CreateWeapon($builder, $weapon_two_name, 5);</div>

<div class="line"><span class="comment">// Create an array from the two `Weapon`s and pass it to the</span></div>

<div class="line"><span class="comment">// `CreateWeaponsVector()` method to create a FlatBuffer vector.</span></div>

<div class="line">$weaps = array($sword, $axe);</div>

<div class="line">$weapons = \MyGame\Sample\Monster::CreateWeaponsVector($builder, $weaps);</div>

</div> </div><p>Now let's create our monster, the <code>orc</code>. For this <code>orc</code>, lets make him <code>red</code> with rage, positioned at <code>(1.0, 2.0, 3.0)</code>, and give him a large pool of hit points with <code>300</code>. We can give him a vector of weapons to choose from (our <code>Sword</code> and <code>Axe</code> from earlier). In this case, we will equip him with the <code>Axe</code>, since it is the most powerful of the two. Lastly, let's fill his inventory with some potential treasures that can be taken once he is defeated.</p>

<p>Before we serialize a monster, we need to first serialize any objects that are contained there-in, i.e. we serialize the data tree using depth-first, pre-order traversal. This is generally easy to do on any tree structures.</p>

<div class="language-cpp"> <div class="fragment"><div class="line"><span class="comment">// Serialize a name for our monster, called "Orc".</span></div>

<div class="line"><span class="keyword">auto</span> name = builder.CreateString(<span class="stringliteral">"Orc"</span>);</div>

<div class="line"><span class="comment">// Create a `vector` representing the inventory of the Orc. Each number</span></div>

<div class="line"><span class="comment">// could correspond to an item that can be claimed after he is slain.</span></div>

<div class="line"><span class="keywordtype">unsigned</span> <span class="keywordtype">char</span> treasure = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};</div>

<div class="line"><span class="keyword">auto</span> inventory = builder.CreateVector(treasure, 10);</div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line"><span class="comment">// Serialize a name for our monster, called "Orc".</span></div>

<div class="line"><span class="keywordtype">int</span> name = builder.createString(<span class="stringliteral">"Orc"</span>);</div>

<div class="line"><span class="comment">// Create a `vector` representing the inventory of the Orc. Each number</span></div>

<div class="line"><span class="comment">// could correspond to an item that can be claimed after he is slain.</span></div>

<div class="line">byte[] treasure = {0, 1, 2, 3, 4, 5, 6, 7, 8, 9};</div>

<div class="line"><span class="keywordtype">int</span> inv = Monster.createInventoryVector(builder, treasure);</div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line"><span class="comment">// Serialize a name for our monster, called "Orc".</span></div>

<div class="line">var name = builder.CreateString(<span class="stringliteral">"Orc"</span>);</div>

<div class="line"><span class="comment">// Create a `vector` representing the inventory of the Orc. Each number</span></div>

<div class="line"><span class="comment">// could correspond to an item that can be claimed after he is slain.</span></div>

<div class="line"><span class="comment">// Note: Since we prepend the bytes, this loop iterates in reverse order.</span></div>

<div class="line">Monster.StartInventoryVector(builder, 10);</div>

<div class="line"> builder.AddByte((byte)i);</div>

<div class="line">var inv = builder.EndVector();</div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line"><span class="comment">// Serialize a name for our monster, called "Orc".</span></div>

<div class="line">name := builder.CreateString(<span class="stringliteral">"Orc"</span>)</div>

<div class="line"><span class="comment">// Create a `vector` representing the inventory of the Orc. Each number</span></div>

<div class="line"><span class="comment">// could correspond to an item that can be claimed after he is slain.</span></div>

<div class="line"><span class="comment">// Note: Since we prepend the bytes, this loop iterates in reverse.</span></div>

<div class="line">sample.MonsterStartInventoryVector(builder, 10)</div>

<div class="line"> builder.PrependByte(byte(i))</div>

<div class="line"><span class="keywordtype">int</span> := builder.EndVector(10)</div>

<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> name = builder.CreateString(<span class="stringliteral">"Orc"</span>)</div>

<div class="line"><a name="l00004"></a><span class="lineno"> 4</span> <span class="comment"># Create a `vector` representing the inventory of the Orc. Each number</span></div>

<div class="line"><a name="l00005"></a><span class="lineno"> 5</span> <span class="comment"># could correspond to an item that can be claimed after he is slain.</span></div>

<div class="line"><a name="l00006"></a><span class="lineno"> 6</span> <span class="comment"># Note: Since we prepend the bytes, this loop iterates in reverse.</span></div>

<div class="line"><a name="l00007"></a><span class="lineno"> 7</span> MyGame.Sample.Monster.MonsterStartInventoryVector(builder, 10)</div>

<div class="line"><a name="l00008"></a><span class="lineno"> 8</span> <span class="keywordflow">for</span> i <span class="keywordflow">in</span> reversed(range(0, 10)):</div>

<div class="line"><a name="l00009"></a><span class="lineno"> 9</span>  builder.PrependByte(i)</div>

<div class="line"><a name="l00010"></a><span class="lineno"> 10</span> inv = builder.EndVector(10)</div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line"><span class="comment">// Serialize a name for our monster, called 'Orc'.</span></div>

<div class="line">var name = builder.createString(<span class="stringliteral">'Orc'</span>);</div>

<div class="line"><span class="comment">// Create a `vector` representing the inventory of the Orc. Each number</span></div>

<div class="line"><span class="comment">// could correspond to an item that can be claimed after he is slain.</span></div>

<div class="line">var treasure = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9];</div>

<div class="line">var inv = MyGame.Sample.Monster.createInventoryVector(builder, treasure);</div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line"><span class="comment">// Serialize a name for our monster, called "Orc".</span></div>

<div class="line">$name = $builder->createString(<span class="stringliteral">"Orc"</span>);</div>

<div class="line"><span class="comment">// Create a `vector` representing the inventory of the Orc. Each number</span></div>

<div class="line"><span class="comment">// could correspond to an item that can be claimed after he is slain.</span></div>

<div class="line">$treasure = array(0, 1, 2, 3, 4, 5, 6, 7, 8, 9);</div>

<div class="line">$inv = \MyGame\Sample\Monster::CreateInventoryVector($builder, $treasure);</div>

</div> </div><p>We serialized two built-in data types (<code>string</code> and <code>vector</code>) and captured their return values. These values are offsets into the serialized data, indicating where they are stored, such that we can refer to them below when adding fields to our monster.</p>

<p><em>Note: To create a <code>vector</code> of nested objects (e.g. <code>table</code>s, <code>string</code>s, or other <code>vector</code>s), collect their offsets into a temporary data structure, and then create an additional <code>vector</code> containing their offsets.</em></p>

<p>For example, take a look at the two <code>Weapon</code>s that we created earlier (<code>Sword</code> and <code>Axe</code>). These are both FlatBuffer <code>table</code>s, whose offsets we now store in memory. Therefore we can create a FlatBuffer <code>vector</code> to contain these offsets.</p>

<div class="language-cpp"> <div class="fragment"><div class="line"><span class="comment">// Place the weapons into a `std::vector`, then convert that into a FlatBuffer `vector`.</span></div>

<div class="line">std::vector<flatbuffers::Offset<Weapon>> weapons_vector;</div>

<div class="line">weapons_vector.push_back(sword);</div>

<div class="line">weapons_vector.push_back(axe);</div>

<div class="line"><span class="keyword">auto</span> weapons = builder.CreateVector(weapons_vector);</div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line"><span class="comment">// Place the two weapons into an array, and pass it to the `createWeaponsVector()` method to</span></div>

<div class="line"><span class="comment">// create a FlatBuffer vector.</span></div>

<div class="line"><span class="keywordtype">int</span>[] weaps = <span class="keyword">new</span> <span class="keywordtype">int</span>[2];</div>

<div class="line">weaps[1] = sword;</div>

<div class="line">weaps[2] = axe;</div>

<div class="line"><span class="comment">// Pass the `weaps` array into the `createWeaponsVector()` method to create a FlatBuffer vector.</span></div>

<div class="line"><span class="keywordtype">int</span> weapons = Monster.createWeaponsVector(builder, weaps);</div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line">var weaps = <span class="keyword">new</span> Offset<Weapon>[2];</div>

<div class="line">weaps[0] = sword;</div>

<div class="line">weaps[1] = axe;</div>

<div class="line"><span class="comment">// Pass the `weaps` array into the `CreateWeaponsVector()` method to create a FlatBuffer vector.</span></div>

<div class="line">var weapons = Monster.CreateWeaponsVector(builder, weaps);</div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line"><span class="comment">// Create a FlatBuffer vector and prepend the weapons.</span></div>

<div class="line"><span class="comment">// Note: Since we prepend the data, prepend them in reverse order.</span></div>

<div class="line">sample.MonsterStartWeaponsVector(builder, 2)</div>

<div class="line">builder.PrependUOffsetT(axe)</div>

<div class="line">builder.PrependUOffsetT(sword)</div>

<div class="line">weapons := builder.EndVector(2)</div>

<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> <span class="comment"># Note: Since we prepend the data, prepend them in reverse order.</span></div>

<div class="line"><a name="l00003"></a><span class="lineno"> 3</span> MyGame.Sample.Monster.MonsterStartWeaponsVector(builder, 2)</div>

<div class="line"><a name="l00004"></a><span class="lineno"> 4</span> builder.PrependUOffsetTRelative(axe)</div>

<div class="line"><a name="l00005"></a><span class="lineno"> 5</span> builder.PrependUOffsetTRelative(sword)</div>

<div class="line"><a name="l00006"></a><span class="lineno"> 6</span> weapons = builder.EndVector(2)</div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line"><span class="comment">// Create an array from the two `Weapon`s and pass it to the</span></div>

<div class="line"><span class="comment">// `createWeaponsVector()` method to create a FlatBuffer vector.</span></div>

<div class="line">var weaps = [sword, axe];</div>

<div class="line">var weapons = MyGame.Sample.Monster.createWeaponsVector(builder, weaps);</div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line"><span class="comment">// Create an array from the two `Weapon`s and pass it to the</span></div>

<div class="line"><span class="comment">// `CreateWeaponsVector()` method to create a FlatBuffer vector.</span></div>

<div class="line">$weaps = array($sword, $axe);</div>

<div class="line">$weapons = \MyGame\Sample\Monster::CreateWeaponsVector($builder, $weaps);</div>

</div> </div><p>To create a <code>struct</code>, use the <code>Vec3</code> class/struct that was generated by <code>flatc</code>:</p>

<div class="language-cpp"> <div class="fragment"><div class="line"><span class="comment">// Create a `Vec3`, representing the Orc's position in 3-D space.</span></div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line"><span class="comment">// Create a `Vec3`, representing the Orc's position in 3-D space.</span></div>

<div class="line"><span class="keywordtype">int</span> pos = Vec3.createVec3(builder, 1.0f, 2.0f, 3.0f);</div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line"><span class="comment">// Create a `Vec3`, representing the Orc's position in 3-D space.</span></div>

<div class="line">var pos = Vec3.CreateVec3(builder, 1.0f, 2.0f, 3.0f);</div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line"><span class="comment">// Create a `Vec3`, representing the Orc's position in 3-D space.</span></div>

<div class="line">pos := sample.CreateVec3(builder, 1.0, 2.0, 3.0)</div>

<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> pos = MyGame.Sample.Vec3.CreateVec3(builder, 1.0, 2.0, 3.0)</div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line"><span class="comment">// Create a `Vec3`, representing the Orc's position in 3-D space.</span></div>

<div class="line">var pos = MyGame.Sample.Vec3.createVec3(builder, 1.0, 2.0, 3.0);</div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line"><span class="comment">// Create a `Vec3`, representing the Orc's position in 3-D space.</span></div>

<div class="line">$pos = \MyGame\Sample\Vec3::CreateVec3($builder, 1.0, 2.0, 3.0);</div>

</div> </div><p>We have now serialized the non-scalar components of the orc, so we can serialize the monster itself:</p>

<div class="language-cpp"> <div class="fragment"><div class="line"><span class="comment">// Set his hit points to 300 and his mana to 150.</span></div>

<div class="line"><span class="comment">// Finally, create the monster using the `CreateMonster` helper function</span></div>

<div class="line"><span class="comment">// to set all fields.</span></div>

<div class="line"><span class="keyword">auto</span> orc = CreateMonster(builder, &pos, mana, hp, name, inventory, Color_Red,</div>

<div class="line"> weapons, Equipment_Weapon, axe.Union());</div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line"><span class="comment">// Create our monster using `startMonster()` and `endMonster()`.</span></div>

<div class="line">Monster.startMonster(builder);</div>

<div class="line">Monster.addPos(builder, pos);</div>

<div class="line">Monster.addName(builder, name);</div>

<div class="line">Monster.addColor(builder, Color.Red);</div>

<div class="line">Monster.addHp(builder, (short)300);</div>

<div class="line">Monster.addInventory(builder, inv);</div>

<div class="line">Monster.addWeapons(builder, weapons);</div>

<div class="line">Monster.addEquippedType(builder, Equipment.Weapon);</div>

<div class="line">Monster.addEquipped(builder, axe);</div>

<div class="line"><span class="keywordtype">int</span> orc = Monster.endMonster(builder);</div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line"><span class="comment">// Create our monster using `StartMonster()` and `EndMonster()`.</span></div>

<div class="line">Monster.StartMonster(builder);</div>

<div class="line">Monster.AddPos(builder, pos);</div>

<div class="line">Monster.AddHp(builder, (short)300);</div>

<div class="line">Monster.AddName(builder, name);</div>

<div class="line">Monster.AddInventory(builder, inv);</div>

<div class="line">Monster.AddColor(builder, Color.Red);</div>

<div class="line">Monster.AddWeapons(builder, weapons);</div>

<div class="line">Monster.AddEquippedType(builder, Equipment.Weapon);</div>

<div class="line">Monster.AddEquipped(builder, axe.Value); <span class="comment">// Axe</span></div>

<div class="line">var orc = Monster.EndMonster(builder);</div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line"><span class="comment">// Create our monster using `MonsterStart()` and `MonsterEnd()`.</span></div>

<div class="line">sample.MonsterStart(builder)</div>

<div class="line">sample.MonsterAddPos(builder, pos)</div>

<div class="line">sample.MonsterAddHp(builder, 300)</div>

<div class="line">sample.MonsterAddName(builder, name)</div>

<div class="line">sample.MonsterAddInventory(builder, inv)</div>

<div class="line">sample.MonsterAddColor(builder, sample.ColorRed)</div>

<div class="line">sample.MonsterAddWeapons(builder, weapons)</div>

<div class="line">sample.MonsterAddEquippedType(builder, sample.EquipmentWeapon)</div>

<div class="line">sample.MonsterAddEquipped(builder, axe)</div>

<div class="line">orc := sample.MonsterEnd(builder)</div>

<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> MyGame.Sample.Monster.MonsterStart(builder)</div>

<div class="line"><a name="l00003"></a><span class="lineno"> 3</span> MyGame.Sample.Monster.MonsterAddPos(builder, pos)</div>

<div class="line"><a name="l00004"></a><span class="lineno"> 4</span> MyGame.Sample.Monster.MonsterAddHp(builder, 300)</div>

<div class="line"><a name="l00005"></a><span class="lineno"> 5</span> MyGame.Sample.Monster.MonsterAddName(builder, name)</div>

<div class="line"><a name="l00006"></a><span class="lineno"> 6</span> MyGame.Sample.Monster.MonsterAddInventory(builder, inv)</div>

<div class="line"><a name="l00007"></a><span class="lineno"> 7</span> MyGame.Sample.Monster.MonsterAddColor(builder,</div>

<div class="line"><a name="l00008"></a><span class="lineno"> 8</span>  MyGame.Sample.Color.Color().Red)</div>

<div class="line"><a name="l00009"></a><span class="lineno"> 9</span> MyGame.Sample.Monster.MonsterAddWeapons(builder, weapons)</div>

<div class="line"><a name="l00010"></a><span class="lineno"> 10</span> MyGame.Sample.Monster.MonsterAddEquippedType(</div>

<div class="line"><a name="l00011"></a><span class="lineno"> 11</span>  builder, MyGame.Sample.Equipment.Equipment().Weapon)</div>

<div class="line"><a name="l00012"></a><span class="lineno"> 12</span> MyGame.Sample.Monster.MonsterAddEquipped(builder, axe)</div>

<div class="line"><a name="l00013"></a><span class="lineno"> 13</span> orc = MyGame.Sample.Monster.MonsterEnd(builder)</div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line"><span class="comment">// Create our monster by using `startMonster()` and `endMonster()`.</span></div>

<div class="line">MyGame.Sample.Monster.startMonster(builder);</div>

<div class="line">MyGame.Sample.Monster.addPos(builder, pos);</div>

<div class="line">MyGame.Sample.Monster.addHp(builder, 300);</div>

<div class="line">MyGame.Sample.Monster.addColor(builder, MyGame.Sample.Color.Red)</div>

<div class="line">MyGame.Sample.Monster.addName(builder, name);</div>

<div class="line">MyGame.Sample.Monster.addInventory(builder, inv);</div>

<div class="line">MyGame.Sample.Monster.addWeapons(builder, weapons);</div>

<div class="line">MyGame.Sample.Monster.addEquippedType(builder, MyGame.Sample.Equipment.Weapon);</div>

<div class="line">MyGame.Sample.Monster.addEquipped(builder, axe);</div>

<div class="line">var orc = MyGame.Sample.Monster.endMonster(builder);</div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line"><span class="comment">// Create our monster by using `StartMonster()` and `EndMonster()`.</span></div>

<div class="line">\MyGame\Sample\Monster::StartMonster($builder);</div>

<div class="line">\MyGame\Sample\Monster::AddPos($builder, $pos);</div>

<div class="line">\MyGame\Sample\Monster::AddHp($builder, 300);</div>

<div class="line">\MyGame\Sample\Monster::AddName($builder, $name);</div>

<div class="line">\MyGame\Sample\Monster::AddInventory($builder, $inv);</div>

<div class="line">\MyGame\Sample\Monster::AddColor($builder, \MyGame\Sample\Color::Red);</div>

<div class="line">\MyGame\Sample\Monster::AddWeapons($builder, $weapons);</div>

<div class="line">\MyGame\Sample\Monster::AddEquippedType($builder, \MyGame\Sample\Equipment::Weapon);</div>

<div class="line">\MyGame\Sample\Monster::AddEquipped($builder, $axe);</div>

<div class="line">$orc = \MyGame\Sample\Monster::EndMonster($builder);</div>

</div> </div><div class="language-cpp"> <br />

<em>Note: Since we passing <code>150</code> as the <code>mana</code> field, which happens to be the default value, the field will not actually be written to the buffer, since the default value will be returned on query anyway. This is a nice space savings, especially if default values are common in your data. It also means that you do not need to be worried of adding a lot of fields that are only used in a small number of instances, as it will not bloat the buffer if unused.</em> <br />

<br />

If you do not wish to set every field in a <code>table</code>, it may be more convenient to manually set each field of your monster, instead of calling <code>CreateMonster()</code>. The following snippet is functionally equivalent to the above code, but provides a bit more flexibility. <br />

</p><div class="fragment"><div class="line"><span class="comment">// You can use this code instead of `CreateMonster()`, to create our orc</span></div>

<div class="line"><span class="comment">// manually.</span></div>

<div class="line">MonsterBuilder monster_builder(builder);</div>

<div class="line">monster_builder.add_pos(&pos);</div>

<div class="line">monster_builder.add_hp(hp);</div>

<div class="line">monster_builder.add_name(name);</div>

<div class="line">monster_builder.add_inventory(inventory);</div>

<div class="line">monster_builder.add_color(Color_Red);</div>

<div class="line">monster_builder.add_weapons(weapons);</div>

<div class="line">monster_builder.add_equipped_type(Equipment_Weapon);</div>

<div class="line">monster_builder.add_equpped(axe);</div>

<div class="line"><span class="keyword">auto</span> orc = monster_builder.Finish();</div>

</div> </div><p>Before finishing the serialization, let's take a quick look at FlatBuffer <code>union Equipped</code>. There are two parts to each FlatBuffer <code>union</code>. The first, is a hidden field <code>_type</code>, that is generated to hold the type of <code>table</code> referred to by the <code>union</code>. This allows you to know which type to cast to at runtime. Second, is the <code>union</code>'s data.</p>

<p>In our example, the last two things we added to our <code>Monster</code> were the <code>Equipped Type</code> and the <code>Equipped</code> union itself.</p>

<p>Here is a repetition these lines, to help highlight them more clearly:</p>

<div class="language-cpp"> <div class="fragment"><div class="line">monster_builder.add_equipped_type(Equipment_Weapon); <span class="comment">// Union type</span></div>

<div class="line">monster_builder.add_equipped(axe); <span class="comment">// Union data</span></div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line">Monster.addEquippedType(builder, Equipment.Weapon); <span class="comment">// Union type</span></div>

<div class="line">Monster.addEquipped(axe); <span class="comment">// Union data</span></div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line">Monster.AddEquippedType(builder, Equipment.Weapon); <span class="comment">// Union type</span></div>

<div class="line">Monster.AddEquipped(builder, axe.Value); <span class="comment">// Union data</span></div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line">sample.MonsterAddEquippedType(builder, sample.EquipmentWeapon) <span class="comment">// Union type</span></div>

<div class="line">sample.MonsterAddEquipped(builder, axe) <span class="comment">// Union data</span></div>

</div> </div> <div class="language-python"> <div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno"> 1</span> MyGame.Sample.Monster.MonsterAddEquippedType( <span class="comment"># Union type</span></div>

<div class="line"><a name="l00002"></a><span class="lineno"> 2</span>  builder, MyGame.Sample.Equipment.Equipment().Weapon)</div>

<div class="line"><a name="l00003"></a><span class="lineno"> 3</span> MyGame.Sample.Monster.MonsterAddEquipped(builder, axe) <span class="comment"># Union data</span></div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line">MyGame.Sample.Monster.addEquippedType(builder, MyGame.Sample.Equipment.Weapon); <span class="comment">// Union type</span></div>

<div class="line">MyGame.Sample.Monster.addEquipped(builder, axe); <span class="comment">// Union data</span></div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line">\MyGame\Sample\Monster::AddEquippedType($builder, \MyGame\Sample\Equipment::Weapon); <span class="comment">// Union type</span></div>

<div class="line">\MyGame\Sample\Monster::AddEquipped($builder, $axe); <span class="comment">// Union data</span></div>

</div> </div><p>After you have created your buffer, you will have the offset to the root of the data in the <code>orc</code> variable, so you can finish the buffer by calling the appropriate <code>finish</code> method.</p>

<div class="language-cpp"> <div class="fragment"><div class="line"><span class="comment">// Call `Finish()` to instruct the builder that this monster is complete.</span></div>

<div class="line"><span class="comment">// Note: Regardless of how you created the `orc`, you still need to call</span></div>

<div class="line"><span class="comment">// `Finish()` on the `FlatBufferBuilder`.</span></div>

<div class="line">builder.Finish(orc); <span class="comment">// You could also call `FinishMonsterBuffer(builder,</span></div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line"><span class="comment">// Call `finish()` to instruct the builder that this monster is complete.</span></div>

<div class="line">builder.finish(orc); <span class="comment">// You could also call `Monster.finishMonsterBuffer(builder, orc);`.</span></div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line"><span class="comment">// Call `Finish()` to instruct the builder that this monster is complete.</span></div>

<div class="line">builder.Finish(orc.Value); <span class="comment">// You could also call `Monster.FinishMonsterBuffer(builder, orc);`.</span></div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line"><span class="comment">// Call `Finish()` to instruct the builder that this monster is complete.</span></div>

<div class="line">builder.Finish(orc)</div>

<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> builder.Finish(orc)</div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line"><span class="comment">// Call `finish()` to instruct the builder that this monster is complete.</span></div>

<div class="line">builder.finish(orc); <span class="comment">// You could also call `MyGame.Example.Monster.finishMonsterBuffer(builder,</span></div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line"><span class="comment">// Call `finish()` to instruct the builder that this monster is complete.</span></div>

<div class="line"> $builder->finish($orc); <span class="comment">// You may also call `\MyGame\Sample\Monster::FinishMonsterBuffer(</span></div>

<div class="line"> <span class="comment">// $builder, $orc);`.</span></div>

</div> </div><p>The buffer is now ready to be stored somewhere, sent over the network, be compressed, or whatever you'd like to do with it. You can access the buffer like so:</p>

<div class="language-cpp"> <div class="fragment"><div class="line"><span class="comment">// This must be called after `Finish()`.</span></div>

<div class="line">uint8_t *buf = builder.GetBufferPointer();</div>

<div class="line"><span class="keywordtype">int</span> size = builder.GetSize(); <span class="comment">// Returns the size of the buffer that</span></div>

<div class="line"> <span class="comment">// `GetBufferPointer()` points to.</span></div>

</div> </div> <div class="language-java"> <div class="fragment"><div class="line"><span class="comment">// This must be called after `finish()`.</span></div>

<div class="line">java.nio.ByteBuffer buf = builder.dataBuffer();</div>

</div> </div> <div class="language-csharp"> <div class="fragment"><div class="line"><span class="comment">// This must be called after `Finish()`.</span></div>

<div class="line">var buf = builder.DataBuffer; <span class="comment">// Of type `FlatBuffers.ByteBuffer`.</span></div>

</div> </div> <div class="language-go"> <div class="fragment"><div class="line"><span class="comment">// This must be called after `Finish()`.</span></div>

<div class="line">buf := builder.FinishedBytes() <span class="comment">// Of type `byte[]`.</span></div>

<div class="line"><a name="l00002"></a><span class="lineno"> 2</span> buf = builder.Output() // Of type `bytearray`.</div>

</div> </div> <div class="language-javascript"> <div class="fragment"><div class="line"><span class="comment">// This must be called after `finish()`.</span></div>

<div class="line">var buf = builder.dataBuffer(); <span class="comment">// Of type `flatbuffers.ByteBuffer`.</span></div>

</div> </div> <div class="language-php"> <div class="fragment"><div class="line"><span class="comment">// This must be called after `finish()`.</span></div>

<div class="line">$buf = $builder->dataBuffer(); <span class="comment">// Of type `Google\FlatBuffers\ByteBuffer`</span></div>

</div> </div><h4>Reading Orc FlatBuffers</h4>

<p>Now that we have successfully created an <code>Orc</code> FlatBuffer, the monster data can be saved, sent over a network, etc. Let's now adventure into the inverse, and deserialize a FlatBuffer.</p>

<p>This seciton requires the same import/include, namespace, etc. requirements as before:</p>