Implement the intern

m3m0r7 · m3m0r7 · commit b276c67e30b7 · 2019-05-08T20:29:50.000+09:00
diff --git a/src/Core/JVM/ConstantPool.php b/src/Core/JVM/ConstantPool.php
@@ -25,7 +25,6 @@ class ConstantPool implements \ArrayAccess, \Countable, \IteratorAggregate
 {
     private $entries = [];
     private $reader;
-    private $isWritable = false;
 
     /**
      * @param ReaderInterface $reader
@@ -52,16 +51,6 @@ public function __construct(ReaderInterface $reader, int $entries)
         }
     }
 
-    /**
-     * @param bool $enable
-     * @return ConstantPool
-     */
-    public function enableWrite(bool $enable): self
-    {
-        $this->isWritable = $enable;
-        return $this;
-    }
-
     /**
      * @return StructureInterface[]
      */
@@ -139,10 +128,6 @@ public function count()
      */
     public function offsetSet($offset, $value)
     {
-        if ($this->isWritable) {
-            $this->entries[$offset] = $value;
-            return;
-        }
         throw new ReadOnlyException('You cannot rewrite datum. The Constant Pool is read-only.');
     }
 
@@ -152,10 +137,6 @@ public function offsetSet($offset, $value)
      */
     public function offsetUnset($offset)
     {
-        if ($this->isWritable) {
-            unset($this->entries[$offset]);
-            return;
-        }
         throw new ReadOnlyException('You cannot rewrite datum. The Constant Pool is read-only.');
     }
 
diff --git a/src/Core/JavaClass.php b/src/Core/JavaClass.php
@@ -4,7 +4,6 @@
 use PHPJava\Core\JVM\AttributePool;
 use PHPJava\Core\JVM\FieldPool;
 use PHPJava\Core\JVM\InterfacePool;
-use PHPJava\Core\JVM\Intern\StringIntern;
 use PHPJava\Core\JVM\MethodPool;
 use PHPJava\Core\JVM\ConstantPool;
 use PHPJava\Core\JVM\Parameters\GlobalOptions;
diff --git a/src/Kernel/Structures/_Utf8.php b/src/Kernel/Structures/_Utf8.php
@@ -2,6 +2,7 @@
 namespace PHPJava\Kernel\Structures;
 
 use PHPJava\Exceptions\NotImplementedException;
+use PHPJava\Exceptions\ReadOnlyException;
 use PHPJava\Utilities\BinaryTool;
 
 class _Utf8 implements StructureInterface
@@ -12,6 +13,7 @@ class _Utf8 implements StructureInterface
 
     private $length = 0;
     private $string = '';
+    private $isWritable = false;
 
     /**
      * @var \PHPJava\Packages\java\lang\_String $stringObject
@@ -32,6 +34,31 @@ public function getLength()
         return $this->length;
     }
 
+    /**
+     * @param bool $enable
+     * @return _Utf8
+     */
+    public function enableWrite(bool $enable): self
+    {
+        $this->isWritable = $enable;
+        return $this;
+    }
+
+    /**
+     * @param string $string
+     * @return _Utf8
+     * @throws ReadOnlyException
+     */
+    public function setString(string $string): self
+    {
+        if ($this->isWritable) {
+            $this->string = $string;
+            return $this;
+        }
+
+        throw new ReadOnlyException('You cannot overwrite constant.');
+    }
+
     public function getString()
     {
         return $this->string;
@@ -42,6 +69,12 @@ public function __toString(): string
         return $this->getString();
     }
 
+    public function setStringObject(\PHPJava\Packages\java\lang\_String $stringObject): self
+    {
+        $this->stringObject = $stringObject;
+        return $this;
+    }
+
     public function getStringObject(): \PHPJava\Packages\java\lang\_String
     {
         return $this->stringObject;
diff --git a/src/Packages/java/lang/_String.php b/src/Packages/java/lang/_String.php
@@ -1,7 +1,9 @@
 <?php
 namespace PHPJava\Packages\java\lang;
 
+use PHPJava\Core\JVM\ConstantPool;
 use PHPJava\Exceptions\NotImplementedException;
+use PHPJava\Exceptions\ReadOnlyException;
 use PHPJava\Packages\java\lang\IndexOutOfBoundsException;
 use PHPJava\Kernel\Structures\_Utf8;
 use PHPJava\Kernel\Types\_Char;
@@ -344,14 +346,32 @@ public function indexOf($a = null, $b = null)
     /**
      * Returns a canonical representation for the string object.
      *
-     * @param mixed $a
+     * @native ConstantPool
+     * @param ConstantPool $cp
      * @return mixed
-     * @throws NotImplementedException
+     * @throws ReadOnlyException
      * @see https://docs.oracle.com/en/java/javase/11/docs/api/java.base/java/lang/package-summary.html#intern
      */
-    public function intern($a = null)
-    {
-        throw new NotImplementedException(__METHOD__);
+    public function intern(ConstantPool $cp)
+    {
+        // Find same string in the Constant Pool
+        foreach ($cp as $key => $value) {
+            if (!($value instanceof _Utf8)) {
+                continue;
+            }
+            /**
+             * @var _Utf8 $value
+             */
+            if ((string) $value === (string) $this->object) {
+                $this->object = $value
+                    ->enableWrite(true)
+                    ->setString((string) $this->object)
+                    ->setStringObject($this)
+                    ->enableWrite(false);
+                break;
+            }
+        }
+        return $this;
     }
 
     /**
