java反射中，Class.forName 和 ClassLoader 載入類的區別

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解釋

在java中Class.forName()和ClassLoader都可以對類進行載入。ClassLoader就是遵循雙親委派模型最終調用啟動類載入器的類載入器，實現的功能是“通過一個類的全限定名來擷取描述此類的二進位位元組流”，擷取到二進位流後放到JVM中。Class.forName()方法實際上也是調用的CLassLoader來實現的

Class.forName(String className)；這個方法的源碼是

<tbody><tr><td class="gutter"><div class="line number1 index0 alt2">1</div><div class="line number2 index1 alt1">2</div><div class="line number3 index2 alt2">3</div><div class="line number4 index3 alt1">4</div><div class="line number5 index4 alt2">5</div><div class="line number6 index5 alt1">6</div></td><td class="code"><div class="container"><div class="line number1 index0 alt2"><code class="java color1">@CallerSensitive</code></div><div class="line number2 index1 alt1"><code class="java spaces">&nbsp;&nbsp;&nbsp;&nbsp;</code><code class="java keyword">public</code> <code class="java keyword">static</code> <code class="java plain">Class&lt;?&gt; forName(String className)</code></div><div class="line number3 index2 alt2"><code class="java spaces">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code class="java keyword">throws</code> <code class="java plain">ClassNotFoundException {</code></div><div class="line number4 index3 alt1"><code class="java spaces">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code class="java plain">Class&lt;?&gt; caller = Reflection.getCallerClass();</code></div><div class="line number5 index4 alt2"><code class="java spaces">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</code><code class="java keyword">return</code> <code class="java plain">forName0(className, </code><code class="java keyword">true</code><code class="java plain">, ClassLoader.getClassLoader(caller), caller);</code></div><div class="line number6 index5 alt1"><code class="java spaces">&nbsp;&nbsp;&nbsp;&nbsp;</code><code class="java plain">}</code></div></div></td></tr></tbody>

java反射中，Class.forName 和 ClassLoader 載入類的區別