blocks|key|24015|text|#include两者都不做，既不“导入”库，也不“导入”类或模块。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|24016|#include指令只是告诉预处理器包含另一个文本文件(源)的内容。就这样。|24017|预处理文件A#include文件B的结果被传递给编译器，就像它们是一个文件一样，文件B被粘贴到文件A中#include指令所在的位置。|24018|为了说明这一点:这一切都发生在之前的任何编译，代码生成。|24019|作为一个副作用，C/C%2B%2B预处理器可以独立于编译器使用，以处理任何类型的文本文件输入。|BOLD|24020|有人可能会争辩说，像#include这样的预处理器语句“实际上不是C/C%2B%2B语言的一部分”，因为它们不是用C/C%2B%2B编写任何程序所必需的，因为它们从来不会传递给编译器。|24021|在(标准)+C/C%2B%2B编程的上下文中不使用表达式import，因为不需要导入任何内容。|24022|C/C%2B%2B模块在编译之前放在源代码级别的上，或者在编译之后由链接器放在一起。|24023|entityMap^0|0|8|0|0|8|0|6|8|1F|8|0|0|V|2|0|A|8|0|O|6|0|K|5|X|5|0^^$0|@$1|2|3|4|5|6|7|W|8|@$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|Z|8|@$9|10|A|11|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|12|8|@$9|13|A|14|B|C]|$9|15|A|16|B|C]]|D|@]|E|$]]|$1|J|3|K|5|6|7|17|8|@]|D|@]|E|$]]|$1|L|3|M|5|6|7|18|8|@$9|19|A|1A|B|N]]|D|@]|E|$]]|$1|O|3|P|5|6|7|1B|8|@$9|1C|A|1D|B|C]]|D|@]|E|$]]|$1|Q|3|R|5|6|7|1E|8|@$9|1F|A|1G|B|C]]|D|@]|E|$]]|$1|S|3|T|5|6|7|1H|8|@$9|1I|A|1J|B|N]|$9|1K|A|1L|B|N]]|D|@]|E|$]]|$1|U|3|-4|5|6|7|1M|8|@]|D|@]|E|$]]]|V|$]]

<code>#include</code> does none of both, neither "importing" libraries, nor classes or modules.

The <code>#include</code> directive just tells the pre-processor to include the contents of another text file (source). That's all.

The result of pre-processing file A <code>#include</code>ing file B is passed to the compiler as if they were one file, with file B pasted into file A at the position where the <code>#include</code> directive was placed.

To expliclity state this: This all happens prior to any compilation, code generation.

As a side effect the C/C++ pre-processor could be used independently from the compiler to process any kind of text file input.

One could argue that pre-processor statements like <code>#include</code> "are not really part of the C/C++ languages", as they are not essentially needed to write any programs in C/C++, as they are never passed to the compiler.

The expression <code>import</code> is not used in the context of (standard) C/C++ programming, as there is nothing to be imported. 

C/C++ modules are put together either on source level prior to compilation or by the linker after compilation.

blocks|key|1936348|text|#include<stdio.h>表示复制此文件中stdio.h的内容，而import+java.util.ArrayList表示如果您在此文件中找不到类，请查看上面提到的导入位置。Java导入不会增加文件的大小，它只是节省了很少的击键次数。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1936349|entityMap^0|0|H|11|Q|0^^$0|@$1|2|3|4|5|6|7|H|8|@$9|I|A|J|B|C]|$9|K|A|L|B|C]]|D|@]|E|$]]|$1|F|3|-4|5|6|7|M|8|@]|D|@]|E|$]]]|G|$]]

<code>#include&lt;stdio.h&gt;</code> means copy the contents of stdio.h in this file, 
while <code>import java.util.ArrayList</code> means if you cann't find a class in this file look into above mentioned import location. Java imports do not increase size of your file it just saves few keystrokes.

blocks|key|1936252|text|在Java中，当您使用import时，您可以导入以下任一项：|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1936253|完整包单个类：import+foo.bar.Baz|1936254|a+|unordered-list-item|1936255|：import+foo.bar.*|1936256|a类的单个静态成员：import+static+foo.bar.Baz.GRUT|1936257|every类的静态成员：import+static+foo.bar.Baz.*|1936258|1936259|1936260|entityMap^0|B|6|0|7|I|0|0|1|G|0|A|U|0|C|R|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@$9|V|A|W|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|X|8|@$9|Y|A|Z|B|C]]|D|@]|E|$]]|$1|H|3|I|5|J|7|10|8|@]|D|@]|E|$]]|$1|K|3|L|5|J|7|11|8|@$9|12|A|13|B|C]]|D|@]|E|$]]|$1|M|3|N|5|J|7|14|8|@$9|15|A|16|B|C]]|D|@]|E|$]]|$1|O|3|P|5|J|7|17|8|@$9|18|A|19|B|C]]|D|@]|E|$]]|$1|Q|3|-4|5|6|7|1A|8|@]|D|@]|E|$]]|$1|R|3|-4|5|6|7|1B|8|@]|D|@]|E|$]]|$1|S|3|-4|5|6|7|1C|8|@]|D|@]|E|$]]]|T|$]]

In Java, when you use <code>import</code>, you import either :

<ul>
<li>a single class : <code>import foo.bar.Baz</code></li>
<li>a full package : <code>import foo.bar.*</code></li>
<li>a single static member of a class : <code>import static foo.bar.Baz.GRUT</code></li>
<li>every static member of a class : <code>import static foo.bar.Baz.*</code></li>
</ul>

blocks|key|4742714|text|C/C%2B%2B+#include指令发生在预处理阶段，简而言之，它的意思是“在这里粘贴作为参数给出的整个头文件(或者任何你喜欢的文本文件)”。新的C%2B%2B标准将有模块(最终)，并且可能与Java的导入相似，也可能不相似(取决于它将如何实现)。有关C%2B%2B提案的更多信息，请访问：http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3347.pdf|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|4742715|Java8还将改进对模块化编程的支持。请参阅：http://openjdk.java.net/projects/jigsaw/|4742716|entityMap|0|LINK|mutability|MUTABLE|url|http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3347.pdf|1|http://openjdk.java.net/projects/jigsaw/^0|6|8|3R|1T|0|0|N|14|1|0^^$0|@$1|2|3|4|5|6|7|R|8|@$9|S|A|T|B|C]]|D|@$9|U|A|V|1|W]]|E|$]]|$1|F|3|G|5|6|7|X|8|@]|D|@$9|Y|A|Z|1|10]]|E|$]]|$1|H|3|-4|5|6|7|11|8|@]|D|@]|E|$]]]|I|$J|$5|K|L|M|E|$N|O]]|P|$5|K|L|M|E|$N|Q]]]]

C/C++ <code>#include</code> directive happens at pre-processing phase and in plain English it means "at this place paste the whole header file(or any text file if you like) that is given as parameter". The new C++ standard will have modules (finally), and may or may not be similar to Java's import (depends how it is going to be implemented). More about this C++ proposal: <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3347.pdf" rel="nofollow">http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2012/n3347.pdf</a>

Java 8 will also have improved support for modular programming. See: <a href="http://openjdk.java.net/projects/jigsaw/" rel="nofollow">http://openjdk.java.net/projects/jigsaw/</a>

blocks|key|4742793|text|我认为关于c的其他答案可能还没有明确的一个方面是，|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4742794|C中的|4742795|+include只复制预处理器阶段的头文件，其中包含函数原型，除此之外没有其他内容。在基本代码编译之后，实际的函数定义仍然位于链接时。|blockquote|4742796|4742797|4742798|一个简单的验证可以通过包含一个头文件，而不是源文件，并从您的代码中调用函数来完成。不会出现编译错误，只有在链接时，它才会抱怨无法定位定义。|4742799|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|O|8|@]|9|@]|A|$]]|$1|G|3|-4|5|6|7|P|8|@]|9|@]|A|$]]|$1|H|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|I|3|J|5|6|7|R|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|S|8|@]|9|@]|A|$]]]|L|$]]

I think one aspect that other answers might have not cleared regarding c is,

<blockquote>
 include in c only copies the header file in the preprocessor phase
 which contains the function prototype, nothing more. The actual
 function definition is still located at link time, after basic code
 compilation.
</blockquote>

A simple verification can be done by including a header file, but not the source file and calling the function from your code. There will be no compilation error and only at link time it would complain not being able to locate the definition.

blocks|key|2629338|text|取决于您实际导入的内容。最小的可导入实体是类，最大的是包。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2629339|因此，如果您需要单个类并导入完整的包，它将引入完整的包。|2629340|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|$]]

Depends on what you actually import. The smallest importable entity is class, the largest is the package. 
So if you need a single class and import complete package it will bring in the complete package.

blocks|key|4742893|text|导入(在Java中)类似于使用(在C%2B%2B中)-正如您所理解的，它们并不完全相同，但非常相似。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4742894|import用于指示编译器，在该编译器中可以找到当前类中使用的类(或子包)。|4742895|include+-+Sven在这里解释得更好--+https://stackoverflow.com/a/3739563/135553|offset|length|4742896|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/a/3739563/135553^0|0|0|P|16|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|R|8|@]|9|@$F|S|G|T|1|U]]|A|$]]|$1|H|3|-4|5|6|7|V|8|@]|9|@]|A|$]]]|I|$J|$5|K|L|M|A|$N|O]]]]

import (in Java) is similar to using (in C++) - 
As you understand they are not exactly same, but very similar.

import is to indicate the compiler where it can find the class (or sub package) used in the current class.

include - Sven explained it better here - <a href="https://stackoverflow.com/a/3739563/135553">https://stackoverflow.com/a/3739563/135553</a>

blocks|key|2629674|text|概括地说：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2629675|在c语言中，当编译器遇到#include语句时，所有指定的头文件将只在include语句时加载，而不管我们是否正在使用这些头文件。因此它被称为静态绑定。|2629676|但是对于Java语言，当编译器遇到import语句时，不会在import语句时加载任何.class文件。在接下来的几行代码中，每当我们使用一个类时，只会加载相应的.class文件。这种类型的加载称为动态加载或按需加载或动态加载。|2629677|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

In general terms :

In c language, when compiler encounters #include statement , all the specified header files will be loaded at the time of include statement only irrespective of whether we are using those header files or not. Hence it is called static binding .

But in case of java language, when compiler encounters import statement no .class file will be loaded at the time of import statement. In the next lines of code whenever we are using a class at that time only the corresponding .class file will be loaded. This type of loading is called dynamic loading or load on demand or load on fly.

blocks|key|4742848|text|include通常指的是C、java，其中它们是平台相关的语言，并且需要直接编译、链接和加载到体系结构的机器指令集上，但是当C%2B%2B指的是java时，它是独立于平台的，其中它可以生成字节码，然后可以解释为二进制代码格式。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4742849|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|$]]

include usually refers to C,C++ lang,where they are of platform dependent languages and need to be compiled,linked and loaded on directly to the machine instruction set of architecture, but where as import refers to java lang,it is of platform independent ,where it can generate byte code and then it can interpreted to binary code format.

Does 'import' in Java behave in the same way as '#include' in C/C++? Specifically, will it include the entire library that it is importing or will it just include the classes and methods that are called in the subsequent code?

'import' in Java vs. '#include' in C/C++

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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Java中的“import”行为是否与C/C++中的“#include”行为相同？具体地说，它是包括正在导入的整个库，还是只包括在后续代码中调用的类和方法？

问Java中的“‘import”与C/C++中的“#include”
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