http://download.eclipse.org/jdtls/snapshots/jdt-language-server-0.68.0-202101202016.tar.gz doesn't exist and breaks install on Mac

Steps to reproduce

Follow installation instructions for Mac OS here: https://ycm-core.github.io/YouCompleteMe/#installation

1. brew install cmake macvim python
2. brew install mono go nodejs
3. cd ~/.vim/bundle/YouCompleteMe
   python3 install.py --all

Expected behaviour

The install breaks at some point:

Rust is installed now. Great!

To get started you need Cargo's bin directory
(/var/folders/m0/6fmggpxj1vzcp5wjftfx__7r0000gp/T/rust_install_lng2fptu/bin) in
your PATH
environment variable. This has not been done automatically.

To configure your current shell, run:
source
/var/folders/m0/6fmggpxj1vzcp5wjftfx__7r0000gp/T/rust_install_lng2fptu/env
info: syncing channel updates for 'nightly-2021-07-29-x86_64-apple-darwin'
info: latest update on 2021-07-29, rust version 1.56.0-nightly (b70888601 2021-07-28)
info: downloading component 'cargo'
info: downloading component 'clippy'
info: downloading component 'rust-docs'
17.0 MiB / 17.0 MiB (100 %) 15.2 MiB/s in 1s ETA: 0s
info: downloading component 'rust-std'
21.0 MiB / 21.0 MiB (100 %) 19.6 MiB/s in 1s ETA: 0s
info: downloading component 'rustc'
75.8 MiB / 75.8 MiB (100 %) 23.7 MiB/s in 3s ETA: 0s
info: downloading component 'rustfmt'
info: installing component 'cargo'
info: installing component 'clippy'
info: installing component 'rust-docs'
17.0 MiB / 17.0 MiB (100 %) 5.7 MiB/s in 2s ETA: 0s
info: installing component 'rust-std'
21.0 MiB / 21.0 MiB (100 %) 15.1 MiB/s in 1s ETA: 0s
info: installing component 'rustc'
75.8 MiB / 75.8 MiB (100 %) 16.0 MiB/s in 4s ETA: 0s
info: installing component 'rustfmt'

nightly-2021-07-29-x86_64-apple-darwin installed - rustc 1.56.0-nightly (b70888601 2021-07-28)

info: default toolchain set to 'nightly-2021-07-29-x86_64-apple-darwin'
info: checking for self-updates
info: downloading component 'rust-src'
info: installing component 'rust-src'
info: downloading component 'rust-analyzer-preview'
info: installing component 'rust-analyzer-preview'
info: component 'rustfmt' for target 'x86_64-apple-darwin' is up to date
info: component 'clippy' for target 'x86_64-apple-darwin' is up to date
Downloading jdt.ls from http://download.eclipse.org/jdtls/snapshots/jdt-language-server-0.68.0-202101202016.tar.gz...
Traceback (most recent call last):
File "/Users/pwolter/.vim/bundle/YouCompleteMe/third_party/ycmd/build.py", line 1185, in
Main()
File "/Users/pwolter/.vim/bundle/YouCompleteMe/third_party/ycmd/build.py", line 1177, in Main
EnableJavaCompleter( args )
File "/Users/pwolter/.vim/bundle/YouCompleteMe/third_party/ycmd/build.py", line 992, in EnableJavaCompleter
DownloadFileTo( url, file_name )
File "/Users/pwolter/.vim/bundle/YouCompleteMe/third_party/ycmd/build.py", line 134, in DownloadFileTo
with urllib.request.urlopen( download_url ) as response:
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 222, in urlopen
return opener.open(url, data, timeout)
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 531, in open
response = meth(req, response)
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 640, in http_response
response = self.parent.error(
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 563, in error
result = self._call_chain(*args)
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 502, in _call_chain
result = func(*args)
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 755, in http_error_302
return self.parent.open(new, timeout=req.timeout)
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 531, in open
response = meth(req, response)
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 640, in http_response
response = self.parent.error(
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 569, in error
return self._call_chain(*args)
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 502, in _call_chain
result = func(*args)
File "/opt/anaconda3/lib/python3.8/urllib/request.py", line 649, in http_error_default
raise HTTPError(req.full_url, code, msg, hdrs, fp)
urllib.error.HTTPError: HTTP Error 404: Not Found

Version of Vim

VIM - Vi IMproved 8.2 (2019 Dec 12, compiled Apr 01 2021 08:32:44)

Environment

MacOS 10.15.7
Term: xterm-256color
zsh shell

Logs and stack traces

No response

从 third_party/ycmd/build.py 中的 EnableJavaCompleter 以及 traceback 中显示的 DownloadFileTo 调用开始；检查 jdt.ls URL 的选择方式。验证替换后的 artifact 或 URL，然后在 macOS 上重新运行 python3 install.py --all，并确认 Java completer 的安装不再因 HTTP 404 而失败。