java - try-with-resources 中的 DigestInputStream 是否会关闭原始 InputStream？

Question

如果我在 try-with-resources block 中声明了 DigestInputStream，是否需要显式关闭原始 InputStream？

例子:

InputStream is = ...;
MessageDigest md = ...;

try (final DigestInputStream digestInputStream = new DigestInputStream(is, md)) {
    // Read the stream...
}

我是否需要手动关闭？

Answer 1

因为 DigestInputStream 是一个 AutoCloseable，所以当您在 try-with-resources block 中声明它时，您不需要手动关闭它。

来自 AutoCloseable 的文档:

The {@link #close()} method of an {@code AutoCloseable} object is called automatically when exiting a {@code try}-with-resources block for which the object has been declared in the resource specification header.

此外，FilterInputStream 重写了 close 方法，该方法关闭了使用的 InputStream。