PHP7 FluentInterface

Structural/FluentInterface/Sql.php

@@ -2,79 +2,51 @@
 
 namespace DesignPatterns\Structural\FluentInterface;
 
-/**
- * class SQL.
- */
 class Sql
 {
     /**
      * @var array
      */
-    protected $fields = array();
+    private $fields = [];
 
     /**
      * @var array
      */
-    protected $from = array();
+    private $from = [];
 
     /**
      * @var array
      */
-    protected $where = array();
+    private $where = [];
 
-    /**
+    public function select(array $fields): Sql
-     * adds select fields.
-     *
-     * @param array $fields
-     *
-     * @return SQL
-     */
-    public function select(array $fields = array())
     {
         $this->fields = $fields;
 
         return $this;
     }
 
-    /**
+    public function from(string $table, string $alias): Sql
-     * adds a FROM clause.
-     *
-     * @param string $table
-     * @param string $alias
-     *
-     * @return SQL
-     */
-    public function from($table, $alias)
     {
         $this->from[] = $table.' AS '.$alias;
 
         return $this;
     }
 
-    /**
+    public function where(string $condition): Sql
-     * adds a WHERE condition.
-     *
-     * @param string $condition
-     *
-     * @return SQL
-     */
-    public function where($condition)
     {
         $this->where[] = $condition;
 
         return $this;
     }
 
-    /**
+    public function __toString(): string
-     * Gets the query, just an example of building a query,
-     * no check on consistency.
-     *
-     * @return string
-     */
-    public function getQuery()
     {
-        return 'SELECT '.implode(',', $this->fields)
+        return sprintf(
-                .' FROM '.implode(',', $this->from)
+            'SELECT %s FROM %s WHERE %s',
-                .' WHERE '.implode(' AND ', $this->where);
+            join(', ', $this->fields),
+            join(', ', $this->from),
+            join(' AND ', $this->where)
+        );
     }
 }

Structural/FluentInterface/Tests/FluentInterfaceTest.php

@@ -4,19 +4,15 @@ namespace DesignPatterns\Structural\FluentInterface\Tests;
 
 use DesignPatterns\Structural\FluentInterface\Sql;
 
-/**
- * FluentInterfaceTest tests the fluent interface SQL.
- */
 class FluentInterfaceTest extends \PHPUnit_Framework_TestCase
 {
     public function testBuildSQL()
     {
-        $instance = new Sql();
+        $query = (new Sql())
-        $query = $instance->select(array('foo', 'bar'))
+                ->select(['foo', 'bar'])
                 ->from('foobar', 'f')
-                ->where('f.bar = ?')
+                ->where('f.bar = ?');
-                ->getQuery();
 
-        $this->assertEquals('SELECT foo,bar FROM foobar AS f WHERE f.bar = ?', $query);
+        $this->assertEquals('SELECT foo, bar FROM foobar AS f WHERE f.bar = ?', (string) $query);
     }
 }

Structural/FluentInterface/uml/FluentInterface.uml

@@ -7,14 +7,11 @@
   </nodes>
   <notes />
   <edges />
-  <settings layout="Hierarchic Group" zoom="1.0" x="108.5" y="84.0" />
+  <settings layout="Hierarchic Group" zoom="1.0" x="25.5" y="14.5" />
-  <SelectedNodes>
+  <SelectedNodes />
-    <node>\DesignPatterns\Structural\FluentInterface\Sql</node>
-  </SelectedNodes>
   <Categories>
     <Category>Fields</Category>
     <Category>Constants</Category>
-    <Category>Constructors</Category>
     <Category>Methods</Category>
   </Categories>
   <VISIBILITY>private</VISIBILITY>