blocks|key|5498787|text|也许这会让事情变得更清楚一些：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|5498788|public+void+getData(Object+o[])+{
++++System.out.println("In+Side+Array");
}

public+void+getData(Object+o)+{
++++System.out.println("In+Side+Object");
}
public+static+void+main(String[]+args)+{
++++Object[]+array+=+null;

++++new+JavaEx().getData(array);
}|code-block|syntax|javascript|5498789|此实现还将打印"In+Side+Array"，因为未初始化的数组可以是null。所以很明显，数组方法是被调用的。|offset|length|style|CODE|5498790|entityMap^0|0|0|Z|4|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|Q|8|@$I|R|J|S|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

Maybe this will make things a bit clearer:

<pre><code>public void getData(Object o[]) {
 System.out.println("In Side Array");
}

public void getData(Object o) {
 System.out.println("In Side Object");
}
public static void main(String[] args) {
 Object[] array = null;

 new JavaEx().getData(array);
}
</code></pre>

This implementation will also print "In Side Array", since an uninitialized array can be <code>null</code>. So it becomes obvious, that the array method is called.

blocks|key|1713441|text|两个getData方法都可以处理null参数。在这种情况下，Java会尝试选择处理更具体类型的方法。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1713442|根据定义，Object是所有Java类的超类，因此在这种情况下，Object[]+(也是一个Object)是更具体的类型，而getData(Object+o[])是更具体的方法。这就是Java选择这种方法的原因。|1713443|entityMap^0|2|7|G|4|0|5|6|W|8|1A|6|1Q|J|0^^$0|@$1|2|3|4|5|6|7|J|8|@$9|K|A|L|B|C]|$9|M|A|N|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|O|8|@$9|P|A|Q|B|C]|$9|R|A|S|B|C]|$9|T|A|U|B|C]|$9|V|A|W|B|C]]|D|@]|E|$]]|$1|H|3|-4|5|6|7|X|8|@]|D|@]|E|$]]]|I|$]]

Both <code>getData</code> methods can handle a <code>null</code> argument. In this situation Java tries to choose the method that handles the more specific type. 

Now <code>Object</code> is by definition the superclass of all Java classes, so in this situation <code>Object[]</code> (which is also an <code>Object</code>) is the more specific type and <code>getData(Object o[])</code> is the more specific method. This is why Java chooses this method.

blocks|key|5498862|text|根据JLS(Java+Language+Specification)确定方法签名时间|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|5498863|5498864|blockquote|5498865|5498866|5498867|第一阶段执行重载解析，不允许装箱或取消装箱转换，也不允许使用可变大小方法调用。如果在此阶段期间未找到适用的方法，则处理继续到第二阶段。|ordered-list-item|5498868|第二阶段执行重载解析，同时允许装箱和拆箱，但仍排除使用可变大小方法调用。如果在此阶段找不到适用的方法，则处理继续到第三阶段。|5498869|第三阶段允许重载与可变大小方法、装箱和取消装箱相结合。|5498870|5498871|在您的示例中：|5498872|5498873|当您通过传递参数null来调用方法getData()时，编译器转到第一阶段，在不执行任何装箱的情况下找到方法签名。|style|CODE|5498874|5498875|因此输出是"In+Side+Array"|5498876|entityMap|0|LINK|mutability|MUTABLE|url|https://docs.oracle.com/javase/specs/jls/se8/html/jls-15.html#jls-15.12.2^0|2|3|0|0|0|0|0|0|0|0|0|0|0|0|8|4|H|9|0|0|0^^$0|@$1|2|3|4|5|6|7|18|8|@]|9|@$A|19|B|1A|1|1B]]|C|$]]|$1|D|3|-4|5|6|7|1C|8|@]|9|@]|C|$]]|$1|E|3|-4|5|F|7|1D|8|@]|9|@]|C|$]]|$1|G|3|-4|5|6|7|1E|8|@]|9|@]|C|$]]|$1|H|3|-4|5|6|7|1F|8|@]|9|@]|C|$]]|$1|I|3|J|5|K|7|1G|8|@]|9|@]|C|$]]|$1|L|3|M|5|K|7|1H|8|@]|9|@]|C|$]]|$1|N|3|O|5|K|7|1I|8|@]|9|@]|C|$]]|$1|P|3|-4|5|6|7|1J|8|@]|9|@]|C|$]]|$1|Q|3|R|5|6|7|1K|8|@]|9|@]|C|$]]|$1|S|3|-4|5|6|7|1L|8|@]|9|@]|C|$]]|$1|T|3|U|5|F|7|1M|8|@$A|1N|B|1O|V|W]|$A|1P|B|1Q|V|W]]|9|@]|C|$]]|$1|X|3|-4|5|6|7|1R|8|@]|9|@]|C|$]]|$1|Y|3|Z|5|6|7|1S|8|@]|9|@]|C|$]]|$1|10|3|-4|5|6|7|1T|8|@]|9|@]|C|$]]]|11|$12|$5|13|14|15|C|$16|17]]]]

According <a href="https://docs.oracle.com/javase/specs/jls/se8/html/jls-15.html#jls-15.12.2" rel="nofollow">JLS</a>(Java Language Specification) for determine method signature time

<blockquote>
 <ol>
 <li>The first phase performs overload resolution without permitting boxing or unboxing conversion, or the use of variable arity method
 invocation. If no applicable method is found during this phase then
 processing continues to the second phase.</li>
 <li>The second phase performs overload resolution while allowing boxing and unboxing, but still precludes the use of variable arity
 method invocation. If no applicable method is found during this phase
 then processing continues to the third phase.</li>
 <li>The third phase allows overloading to be combined with variable arity methods, boxing, and unboxing.</li>
 </ol>
</blockquote>

In Your example: 

<blockquote>
 when you call method <code>getData()</code> by passing argument <code>null</code> the compiler go to first
 phase and found method signature without performing any boxing.
 
 So that output is "In Side Array"
</blockquote>

blocks|key|1453970|text|https://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.12.2.5|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|1453971|“如果多个成员方法既可访问又适用于方法调用，则必须选择一个成员方法来为运行时方法调度提供描述符。Java编程语言使用的规则是选择最具体的方法。|1453972|非正式的直觉是，如果第一个方法处理的任何调用可以传递给另一个方法，而不会出现编译时类型错误，则一个方法比另一个方法更具体。|1453973|entityMap|0|LINK|mutability|MUTABLE|url^0|0|23|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@$A|P|B|Q|1|R]]|C|$]]|$1|D|3|E|5|6|7|S|8|@]|9|@]|C|$]]|$1|F|3|G|5|6|7|T|8|@]|9|@]|C|$]]|$1|H|3|-4|5|6|7|U|8|@]|9|@]|C|$]]]|I|$J|$5|K|L|M|C|$N|4]]]]

<a href="https://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.12.2.5" rel="nofollow">https://docs.oracle.com/javase/specs/jls/se7/html/jls-15.html#jls-15.12.2.5</a>

"If more than one member method is both accessible and applicable to a method invocation, it is necessary to choose one to provide the descriptor for the run-time method dispatch. The Java programming language uses the rule that the most specific method is chosen.

The informal intuition is that one method is more specific than another if any invocation handled by the first method could be passed on to the other one without a compile-time type error."

<pre><code>public void getData(Object o[]) {
 System.out.println("In Side Array");
}

public void getData(Object o) {
 System.out.println("In Side Object");
}

public static void main(String[] args) {
 new JavaEx().getData(null);
}
</code></pre>

Here it's printing Array block why, Why it's not printing Object block?

What is the output of this Core java Code?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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public void getData(Object o[]) {    System.out.println("In Side Array");}public void getData(Object o) {    System.out.println("In Side Object");}public static...

问这个核心java代码的输出是什么？
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问这个核心java代码的输出是什么？EN