做这种事并不常见，我不会通常这样做。

It is not common practice to do this kind of thing, and I wouldn't do it normally.

这些内部块（即 {...} ）可用于以下几个目的：

Those inner blocks ( i.e. { ... } ) can serve a couple of purposes:

• 块限制在其中声明的任何变量的范围;例如。

• Blocks limit the scope of any variables declared within them; e.g.

public void foo() {
    int i = 1;
    { 
        int j = 2;
    }
    // Can't refer to the "j" declared here.  But can declare a new one.
    int j = 3;
}

但是，我不建议这样做。 IMO，***使用不同的变量名称或将代码重构为更小的方法。无论哪种方式，大多数Java程序员都会认为 {和} 是令人讨厌的视觉混乱。

However, I wouldn't recommend doing this. IMO, it's better to use different variable names OR refactor the code into smaller methods. Either way, most Java programmers would regard the { and } as annoying visual clutter.

可以使用块来附加标签。

Blocks can be used to attach labels.

HERE : {
    ...
    break HERE;  // breaks to the statement following the block
    ...
}

但是，在实践中，你几乎看不到带标签的断言。而且因为它们非常不寻常，它们往往会使代码的可读性降低。

However, in practice you hardly ever see labelled break statements. And because they are so unusual, they tend to render the code less readable.