java 语言规范上下文中的 "binary name of a class" 是什么？
What is "binary name of a class" in java language specification context?
在阅读 class 加载程序时，我遇到了二进制名称的概念，但我不太了解它。
你能解释一下 java class 的二进制名称是什么以及为什么 package + className 不够用吗（我猜是因为内部 classes ，但这是唯一的原因）吗？
谢谢
内心class并不是唯一的原因；本地 classes、匿名 classes 和类型变量也有二进制名称。
来自Java语言规范（§13.1）：
The class or interface must be named by its binary name, which must meet the following constraints:
The binary name of a top level type (§7.6) is its canonical name (§6.7).
The binary name of a member type (§8.5, §9.5) consists of the binary name of its immediately enclosing type, followed by $, followed by the simple name of the member.
The binary name of a local class (§14.3) consists of the binary name of its immediately enclosing type, followed by $, followed by a non-empty sequence of digits, followed by the simple name of the local class.
The binary name of an anonymous class (§15.9.5) consists of the binary name of its immediately enclosing type, followed by $, followed by a non-empty sequence of digits.
The binary name of a type variable declared by a generic class or interface (§8.1.2, §9.1.2) is the binary name of its immediately enclosing type, followed by $, followed by the simple name of the type variable.
The binary name of a type variable declared by a generic method (§8.4.4) is the binary name of the type declaring the method, followed by $, followed by the descriptor of the method (JVMS §4.3.3), followed by $, followed by the simple name of the type variable.
The binary name of a type variable declared by a generic constructor (§8.8.4) is the binary name of the type declaring the constructor, followed by $, followed by the descriptor of the constructor (JVMS §4.3.3), followed by $, followed by the simple name of the type variable.
至于二进制名称的用途，这在同一节中给出：
A reference to another class or interface type must be symbolic, using the binary name of the type.
也就是说，在编译的字节码中 classes 是通过它们的二进制名称引用的，而不仅仅是它们的规范名称。
一个很好的理由是两个 class 可以有相同的规范名称：例如，规范名称 A.B 可以是一个 class 命名为 B 在名为 A 的包中，或名为 B 的 class 声明为默认包中名为 A 的 class 的内部 class .这两个 classes 的二进制名称分别是 A.B 和 A$B。
另一个原因是有些 class 根本没有规范名称 - 例如，“本地 class 没有规范名称。” (§6.7).
在阅读 class 加载程序时，我遇到了二进制名称的概念，但我不太了解它。
你能解释一下 java class 的二进制名称是什么以及为什么 package + className 不够用吗（我猜是因为内部 classes ，但这是唯一的原因）吗？ 谢谢
内心class并不是唯一的原因；本地 classes、匿名 classes 和类型变量也有二进制名称。
来自Java语言规范（§13.1）：
The class or interface must be named by its binary name, which must meet the following constraints:
The binary name of a top level type (§7.6) is its canonical name (§6.7).
The binary name of a member type (§8.5, §9.5) consists of the binary name of its immediately enclosing type, followed by $, followed by the simple name of the member.
The binary name of a local class (§14.3) consists of the binary name of its immediately enclosing type, followed by $, followed by a non-empty sequence of digits, followed by the simple name of the local class.
The binary name of an anonymous class (§15.9.5) consists of the binary name of its immediately enclosing type, followed by $, followed by a non-empty sequence of digits.
The binary name of a type variable declared by a generic class or interface (§8.1.2, §9.1.2) is the binary name of its immediately enclosing type, followed by $, followed by the simple name of the type variable.
The binary name of a type variable declared by a generic method (§8.4.4) is the binary name of the type declaring the method, followed by $, followed by the descriptor of the method (JVMS §4.3.3), followed by $, followed by the simple name of the type variable.
The binary name of a type variable declared by a generic constructor (§8.8.4) is the binary name of the type declaring the constructor, followed by $, followed by the descriptor of the constructor (JVMS §4.3.3), followed by $, followed by the simple name of the type variable.
至于二进制名称的用途，这在同一节中给出：
A reference to another class or interface type must be symbolic, using the binary name of the type.
也就是说，在编译的字节码中 classes 是通过它们的二进制名称引用的，而不仅仅是它们的规范名称。
一个很好的理由是两个 class 可以有相同的规范名称：例如，规范名称 A.B 可以是一个 class 命名为 B 在名为 A 的包中，或名为 B 的 class 声明为默认包中名为 A 的 class 的内部 class .这两个 classes 的二进制名称分别是 A.B 和 A$B。
另一个原因是有些 class 根本没有规范名称 - 例如，“本地 class 没有规范名称。” (§6.7).