blocks|key|3665081|text|static块被称为“静态初始化块”。它与常规构造函数非常相似，只是它只能初始化静态变量。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|3665082|我发现它在初始化一些静态变量可能抛出一个您想要处理或至少记录的异常时很有用。它在初始化静态最终变量时特别有用。|3665083|您可以在此处阅读有关静态初始化块的更多信息：Initializing+Fields|3665084|entityMap|0|LINK|mutability|MUTABLE|url|http://download.oracle.com/javase/tutorial/java/javaOO/initial.html^0|0|6|0|0|M|J|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@$9|S|A|T|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|U|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|V|8|@]|D|@$9|W|A|X|1|Y]]|E|$]]|$1|J|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|K|$L|$5|M|N|O|E|$P|Q]]]]

The <code>static</code> block is called a "static initialization block." It is very similar to a regular constructor except that it can only initialize static variables.

I have found it to be useful when initialization of some static variable may throw an exception that you would like to handle or at least log. It is especially useful in the initialization of static final variables.

You may read more about static initialization blocks here: <a href="http://download.oracle.com/javase/tutorial/java/javaOO/initial.html" rel="nofollow">Initializing Fields</a>

blocks|key|3379546|text|它执行一个代码块而不需要这个类的实例，也就是说，只要类加载器加载了这个类。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|3379547|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

It executes a block of code without requiring an instance of this class, i.e. as soon as the class loader loads the class.

blocks|key|3379637|text|这就变成了一个static+initialisation+block，它可以被写成一个静态方法。|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|3379638|entityMap|0|LINK|mutability|MUTABLE|url|http://download.oracle.com/javase/tutorial/java/javaOO/initial.html^0|7|R|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@$A|M|B|N|1|O]]|C|$]]|$1|D|3|-4|5|6|7|P|8|@]|9|@]|C|$]]]|E|$F|$5|G|H|I|C|$J|K]]]]

That becomes a <a href="http://download.oracle.com/javase/tutorial/java/javaOO/initial.html" rel="nofollow">static initialisation block</a>, which can be written as a static method.

blocks|key|114730|text|它是一个静态初始化器。一旦装入了类，它就会运行，并且它的结果可以存储在静态成员中。它用于初始化需要比常规的新Xyz()+(如列表或地图)更多的静态成员...|type|unstyled|depth|inlineStyleRanges|entityRanges|data|114731|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

It's a static initializer. It's run once the class is loaded and it's results can be stored in static members. It's used to initialize static members that require more than the regular new Xyz() (like Lists or Maps)...

blocks|key|1764937|text|它是一个静态初始化器。它允许您指定在加载类时，在创建任何实例之前发生的事情。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1764938|如果一个异常是从静态初始化器抛出的，这是非常令人困惑的，很难判断它是从哪里来的。在静态初始化器中做的任何事情都应该有一个try-catch，并记录异常。这是一个很好的语言特性，如果你能避免的话。|1764939|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

It's a static initializer. It lets you specify things that happen at the time that the class is loaded, before any instance is created.

If an exception is thrown from a static initializer it's very confusing, it's hard to tell where it came from. Anything that you do in a static initializer should have a try-catch around it and have the exception get logged. It's a good language feature to avoid if you can.

blocks|key|114746|text|这意味着在将类加载到JVM中时，将首先执行静态块中的这一部分。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|114747|执行下面这个简单的程序可能会让事情变得更清晰|114748|public+class+Test123+{
++static{
++++System.out.println("Hello+from+static+block");
++}

++public+static+void+main(String[]+args)+{
++++System.out.println("In+main");
++}
}|code-block|syntax|javascript|114749|上面的输出将是|114750|Hello+from+static+block+
In+main|114751|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|P|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|Q|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|L|5|F|7|S|8|@]|9|@]|A|$G|H]]|$1|M|3|-4|5|6|7|T|8|@]|9|@]|A|$]]]|N|$]]

It means that you will have this section which is inside the static block extecuted FIRST on load of the class into the JVM.

Execute the following simple program might make things clearer

<pre><code>public class Test123 {
 static{
 System.out.println("Hello from static block");
 }

 public static void main(String[] args) {
 System.out.println("In main");
 }
}
</code></pre>

The output to the above will be

<pre><code>Hello from static block 
In main
</code></pre>

What does

<pre><code>static{
 //something
}
</code></pre>

declared inside a class definition body mean?

<pre><code>public class A extends B{
 static {
 C.register(new C(A.class,
 (byte) D.x.getCode()) {
 public DataSerializable newInstance() {
 return new A();
 }
 }
 );
 }
 }
</code></pre>

Java syntax question

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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什么是static{    //something}在类定义体内声明的意思是什么？public class A extends B{     static {          C.register(new C(A.class,                    (byte) D.x.getCode()) {                         public DataSeriali

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