这个问题的准确措辞有点误导:它不是JVM"或编译器" 因为有多个 JVM 供应商(jrockit 是一个，IBM 是另一个)和 多个编译器.

The precise phrasing of the question is slightly misleading: it is not "the JVM" or "the compiler" as there are multiple JVM vendors (jrockit is one, IBM another) and multiple compilers out there.

• Sun JVM 是用 C 编写的，尽管不一定如此 - 在您的机器上运行的 JVM 是一个平台-dependent 可执行，因此 可以 最初是用任何语言编写的.例如，最初的 IBM JVM 是用 Smalltalk

• The Sun JVM is written in C, although this need not be the case - the JVM as it runs on your machine is a platform-dependent executable and hence could have been originally written in any language. For example, the original IBM JVM was written in Smalltalk

Java 库(java.lang、java.util 等，通常称为Java API)本身就是用 Java 编写，尽管标记为 native 的方法将用 C 或 C++ 编写.

The Java libraries (java.lang, java.util etc, often referred to as the Java API) are themselves written in Java, although methods marked as native will have been written in C or C++.

相信Sun提供的Java编译器也是用Java编写的.(虽然同样有多个编译器)

I believe that the Java compiler provided by Sun is also written in Java. (Although again, there are multiple compilers out there)